I do not get it any ideas?
:I do not get it any ideas?
:
Here is a link to the schematic. Might have to copy and paste it.
http://img196.imageshack.us/img196/9977/461203.png
::I do not get it any ideas?
::
:
:
:Here is a link to the schematic. Might have to copy and paste it.
:
:http://img196.imageshack.us/img196/9977/461203.png
:
Hi Bubba,
Don't be sure that you don't have two defects. I recommend that you troubleshoot the radio as though the phono wans't there.
BTW, they share a switch, too.
All the Best,
Bill Grimm
:::I do not get it any ideas?
:::
::
::
::Here is a link to the schematic. Might have to copy and paste it.
::
::http://img196.imageshack.us/img196/9977/461203.png
::
:Hi Bubba,
: Don't be sure that you don't have two defects. I recommend that you troubleshoot the radio as though the phono wans't there.
:
: BTW, they share a switch, too.
:
:All the Best,
:
:Bill Grimm
:
Funny you should say that I found the switch when I was scouring the schem. That may be the culprit.
Will get back on this after checking it.
:::I do not get it any ideas?
:::
::
::
::Here is a link to the schematic. Might have to copy and paste it.
::
::http://img196.imageshack.us/img196/9977/461203.png
::
:Hi Bubba,
: Don't be sure that you don't have two defects. I recommend that you troubleshoot the radio as though the phono wans't there.
:
: BTW, they share a switch, too.
:
:All the Best,
:
:Bill Grimm
:
Funny you should say that I found the switch when I was scouring the schem after I wrote this last night. That may be the culprit.
Will get back on this after checking it.
:::I do not get it any ideas?
:::
::
::
::Here is a link to the schematic. Might have to copy and paste it.
::
::http://img196.imageshack.us/img196/9977/461203.png
::
:Hi Bubba,
: Don't be sure that you don't have two defects. I recommend that you troubleshoot the radio as though the phono wans't there.
:
: BTW, they share a switch, too.
:
:All the Best,
:
:Bill Grimm
:
Funny you should say that I found the switch when I was scouring the schem after I wrote this last night. That may be the culprit.
Will get back on this after checking it.
:I do not get it any ideas?
:
You know I think the cartridge is dead. It is a Shure P90S . Can these be repaired? I mean what is inside, what causes these to die and why can they not be repaired? What is it that can or cannot be repaired? Does the crystal just wear out? I might drill out the rivets and see what is inside. Is this a waste of time?
THANX sorry but I know nothing about crystal cartridges.. THX
Bubba
Doug
:
I do think the cartridge is bad when I remove it and put a signal generator on the red and black wires it came through loud and clear. But when I put the cartridge back in and scrape the needle with my finger when it is plugged in there is nothing but light hum. I seem to remember it was a little distorted before so it would not surprise me if it was bad and my test kind of proves it does it not?
I did go through checking all the voltages prior to this, in the output anyway and they were all bang on good. I do think this cartridge is bad. I do think there are 2 different problems. I do think the radio issue is in the early RF stages. I am going to trouble shoot the radio next.
How can I troubleshoot the Radio stages with no RF generator? Any tricks? The audio stage is definatly working. I will check the DC voltages.. Man this chassis is compact and a Pain in the arse..
Yes here is a photo of the Crystal.
http://img809.imageshack.us/img809/1426/shurep90s.jpg
Looks like it is bulging and the black paint on it is cracked open. I wish I knew the science behind how this works? Anyone got 5 minutes to explain it? I don't understand how a neddle vibrating a triangle with a chunk of chalk in it can generate a sine wave? LOL.
I have not messed with it other than drilling out the rivets which I could always put back with screws. I made the troubleshooting mistake because both Radio and phono were not working of assuming it had to be in the output amplifier stage. Sometimes we have too much experience and it leads us in the wrong direction. Someone above called it. Next time I will not make that conclusion. Yup I tested all the tubes.
:In the riders information there is a tube voltage chart. The oscillator is where you might start. This set does have the loctal type tubes. They are known for dirty pin contacts. Remove the tubes and clean all there pins.( May have to scrap or sand them ) The old paper and wax capacitors should all be replaced. The old filter capacitors too. Your audio section seems to be working. ( I take it you have tested the tubes ) Other testing can also be done. Such as the continuity of oscillator coils ( T5 ) RF coils ( T6 ) and both IF transformers primary and secondary ( T1 & T2 ) The phonograph cartridge you have proven is bad.
:
Early electronic phonographs used a piezo-electric crystal for pickup, where the mechanical movement of the stylus in the groove generates a proportional electrical voltage by creating stress within a crystal (typically Rochelle salt).
A problem is with the nature of the crystal itself: it is hydroscopic and tries to absorb moisture from the air and dissolves it.
OK so the brass neddle vibrates the crystal (mechanical energy) and this puts stress on the crystal and thus generates "electrical energy" in the way of tiny voltages? This is a transducer right?
Thanx for taking th time Warren.
:In a nut shell.
:
:Early electronic phonographs used a piezo-electric crystal for pickup, where the mechanical movement of the stylus in the groove generates a proportional electrical voltage by creating stress within a crystal (typically Rochelle salt).
:A problem is with the nature of the crystal itself: it is hydroscopic and tries to absorb moisture from the air and dissolves it.
:
This electric copy of the mechanical copy of the sound originally recorded onto the disc is sent to the amplifier, whose operation you should already understand. The output of the amplifier, whose voltage polarity changes direction pretty much exactly as the voltage fed into it, but with much increased amplitude (the actual voltage itself), is fed to the speaker. Voltage fluctuations become magnetic fluctuations, which react with the permanent magnet of the speaker, and cause mechanical movement, which is transferred to the cone.
Nothing magical here. Just physics at work. Piezo electric crystals are used for many things, including generating a spark for some cigarette lighters and gas grills. The snap of the lever on the lighter jars a crystal so heavily that it creates a great voltage, which is enough to jump a small spark gap and ignite flammable gas passing by.
Rochelle salt happened to be a very economical material for making excellent crystals that would put out relatively high voltages. Unfortunately, as Warren said, it absorbs water, and with time the material used to seal it will fail, and the crystal will turn into chalky salt as it absorbs moisture from the air.
T.
Any othere alternatives?
THX
Bubba
:I do not pretend to have all of the details of piezo electric crystals memorized, but the basics are as follows: Crystals have their atoms arranged in certain very orderly ways. Some crystals are very well suited as piezo electric crystals, and if they are cut a certain way and connected to an electric circuit in a certain way, when they are vibrated, electrons are knocked loose and moved around, corresponding to the vibrations imposed upon them, and will, of course, displace electrons in the electric circuit in correspondence to those displaced in the crystal. The movement of electrons is typically proportional to the physical movement of the crystal. If the needle moves back and forth in a groove, it will twist the crystal in a corresponding way (though somewhat less-so due to rubber damping typically employed). The crystal will displace electrons corresponding to its movement, first one way as the groove moves one way, and then the other, as the mechanical movement heads in the other way.
:
:This electric copy of the mechanical copy of the sound originally recorded onto the disc is sent to the amplifier, whose operation you should already understand. The output of the amplifier, whose voltage polarity changes direction pretty much exactly as the voltage fed into it, but with much increased amplitude (the actual voltage itself), is fed to the speaker. Voltage fluctuations become magnetic fluctuations, which react with the permanent magnet of the speaker, and cause mechanical movement, which is transferred to the cone.
:
:Nothing magical here. Just physics at work. Piezo electric crystals are used for many things, including generating a spark for some cigarette lighters and gas grills. The snap of the lever on the lighter jars a crystal so heavily that it creates a great voltage, which is enough to jump a small spark gap and ignite flammable gas passing by.
:
:Rochelle salt happened to be a very economical material for making excellent crystals that would put out relatively high voltages. Unfortunately, as Warren said, it absorbs water, and with time the material used to seal it will fail, and the crystal will turn into chalky salt as it absorbs moisture from the air.
:
:T.
:
You can try to grow your own salt crystal, and cut it, but this is tedious, and salt crystals do what the one in your cartridge did. If you want more permanent results, you could gut a cheap modern stereo crystal cartridge that uses non-water soluble crystals, and use one or both of them, or you could have it rebuilt by West-Tech Services, or buy a rebuilt one from them, or fit the player with a stereo cartridge wired mono, as they are more gentle to records, and reduce vertical modulation response (surface noise) greatly, though they require a lighter tone-arm and a free lateral bearing, as if the tone arm is heavy and/or if lateral movement is stiff, the cartridge won't track properly. There are some pretty stiff cheapies ($14) on eBay that can work in a lot of heavier pick-ups without too much modification.
I'd say that the easiest route would be to get a rebuilt one from West-Tech. The newer style crystals won't put out as much voltage as the salt crystal, and will be quieter, but will last longer. Same is true with a more modern stereo cartridge. The stereo cartridge is the route I went, as it sounds better, and is gentler to my records, which, in my opinion, are far more important than the originality of the pick-up, but then I have a nice collection of records which I personally selected, and not just some junk records I don't care about. They are not replaceable, and so I would like them to last as long as possible.
If you use a pick-up that doesn't have an output voltage that suits your liking, you can build a small and simple pre-amp for your phonograph, regardless of its design. A 6C4 will work both for 6 volt AC supplies and 150mA AC/DC supplies. It is compact, and can either be built onto a compact sub-chassis, or can be somehow fitted onto the radio's chassis, if that is preferred.
T.
I have no continuity like the other plates to the electrolytic cap.. If it is blown then what? Can I get another 22ohm coil?
:Wierd Philco Issue. The set turns on. I get a faint hum. Neither the Audio from Phonograph nor Radio come through the speaker though. When I turn the volume up and down the faint hum is louder or quieter as if the amplifier section is working normally.. I put a signal into the center and outer wiper of the pot and I can hear it and adjust the volume up and down. It is like the amplifier section is good,, all DC voltages are right in the output section. The only thing that the radio and phono have in common is the volume pot I thought. Both Radio and Phono can't be outputting nothing can they? Pretty unlikely but from the pot back I can hear output? What is going on?
:I do not get it any ideas?
:
My cartridge is a Shure P90S
:In another post ( GE VRII cartridge ) Jerry has said he has 1000 needles and cartridges. May ask if he has a replacement for your phonograph.
:
|
:
:Will do, Thanx Warren will check the tube tomorrow and then the coil.
:
:My cartridge is a Shure P90S
:
:
::In another post ( GE VRII cartridge ) Jerry has said he has 1000 needles and cartridges. May ask if he has a replacement for your phonograph.
::
:
:
I opened up the can and it WAS open.. I tried to find the end but no dice. Then I unwound it for some fun and learning. Then I wound it back up by hand until I measured 20 ohms. Then I put it all back. Now I have 173 on pin 2 like I should and all the DC voltages are what they should be on all tubes. Unfortunatly I am not being flooded with stations or anything else. Only can hear faint hum of the audio amplifier. Pot is slightly scratchy when I move it. Is winding that coil back up by hand gonna work? Or have I screwed it now and need to replace it.
It seems that the DC and AC voltages all check out but the RF part, nothing.. FRUSTRATING.
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba . . . . .
:
:
:Looks like your phono problem was related to a dead xtal, with no fallacy within your sets power supply/ audio amp /speaker sections.
:
:
:Your then presence of that paltry 22V B+ voltage level on the 7B7 plate is then suggesting of a discontinuity of the primary 20 ohm winding of the plate coil winding of the 2nd IF transformer.
:
:
:Why don't you go back to that plate of the IF tube and monitor that 22 volts again and then flip the phono/radio switch to its phono position and then confirm if that present 22 volt level jumps to any higher level.
:Logic being, with that cathode then floating, there should be absolute minimal conduction of the IF tube , with no loading down of the B+ supply, and almost the full 170 V supply level, now being read at the plate of the IF amp.
:
:
:Reinstate the phono/radio BACK to its radio position !
:
:
:If you are still reading only 22V then, assuredly your primary coil just must be OPEN, with you only getting that static 22 volts of feed thru from any conductive creeping crud in the circuitry path.
:
:
:Upon a teardown of the IF and you don’t hopefully find a rosin joint at the two wire connections to the mica leaf trimmer capacitor . . . or its causing a corrosive eat up and the wire opening up. . . . there is an immediate work around test that can be done by placing a 10k resistor from 170 B+ supply to the 7B7 plate.
:
:
:Then you need a bit of capacitive coupling by taking a length of INSULATED wire which will reach from the plate lead of that 10K resistor over to pin 6 of the 7C6.
:
:
:Initially tightly spiral about 3 or so turns around the 10k resistors plate side lead, in order to form a freebie "gimmick" capacitor, in order to extract a bit of that amplified 456 energy to pass on thru the wire to the pin 6 of the 7C6 where you temp solder tack on the very end of that wire to its pin 6.
:
:
:Upon power up and retesting . . .if you are now being flooded with incoming stronger stations . . . . you need to look back into the internal fine wire connections of that IF transformer windings primary, yet again, ever so more closely.
:
:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
::Will do, Thanx Warren will check the tube tomorrow and then the coil.
::
::My cartridge is a Shure P90S
::
::
:
:
::
:::In another post ( GE VRII cartridge ) Jerry has said he has 1000 needles and cartridges. May ask if he has a replacement for your phonograph.
:::
::
::
:
:
Any suggestions? I am stumped. I know this much. The audio section and power section are good. It is either the IF osc or a problem in the RF tuner shunting the RF signal. I think anyway. These 2 are my weakest areas. I am good with Power supplies and Amplifier sections but for some reason maybe lack of experience I find the RF and IF a little overwhelming. I will post all voltages later. Might need a little help on this one. I am going to take the chassis out and put it on a table so it is easier to work on. I could kill Philco or the person there who designed this chassis as it is too small and tight and layers of wire making it hard to manoeuvre in the chassis. I also dislike those metal 8 pin short tubes. They are so hard to get out. heh oh well.
I may need a new coil but it measured correctly 20 ohms and I have voltage on Pin 2 now but still no Radio stations.
:
:
:
:
:
:I opened up the can and it WAS open.. I tried to find the end but no dice. Then I unwound it for some fun and learning. Then I wound it back up by hand until I measured 20 ohms. Then I put it all back. Now I have 173 on pin 2 like I should and all the DC voltages are what they should be on all tubes. Unfortunatly I am not being flooded with stations or anything else. Only can hear faint hum of the audio amplifier. Pot is slightly scratchy when I move it. Is winding that coil back up by hand gonna work? Or have I screwed it now and need to replace it.
:
:It seems that the DC and AC voltages all check out but the RF part, nothing.. FRUSTRATING.
:
:
:
:
:
:
:
:
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Bubba . . . . .
::
::
::Looks like your phono problem was related to a dead xtal, with no fallacy within your sets power supply/ audio amp /speaker sections.
::
::
::Your then presence of that paltry 22V B+ voltage level on the 7B7 plate is then suggesting of a discontinuity of the primary 20 ohm winding of the plate coil winding of the 2nd IF transformer.
::
::
::Why don't you go back to that plate of the IF tube and monitor that 22 volts again and then flip the phono/radio switch to its phono position and then confirm if that present 22 volt level jumps to any higher level.
::Logic being, with that cathode then floating, there should be absolute minimal conduction of the IF tube , with no loading down of the B+ supply, and almost the full 170 V supply level, now being read at the plate of the IF amp.
::
::
::Reinstate the phono/radio BACK to its radio position !
::
::
::If you are still reading only 22V then, assuredly your primary coil just must be OPEN, with you only getting that static 22 volts of feed thru from any conductive creeping crud in the circuitry path.
::
::
::Upon a teardown of the IF and you don’t hopefully find a rosin joint at the two wire connections to the mica leaf trimmer capacitor . . . or its causing a corrosive eat up and the wire opening up. . . . there is an immediate work around test that can be done by placing a 10k resistor from 170 B+ supply to the 7B7 plate.
::
::
::Then you need a bit of capacitive coupling by taking a length of INSULATED wire which will reach from the plate lead of that 10K resistor over to pin 6 of the 7C6.
::
::
::Initially tightly spiral about 3 or so turns around the 10k resistors plate side lead, in order to form a freebie "gimmick" capacitor, in order to extract a bit of that amplified 456 energy to pass on thru the wire to the pin 6 of the 7C6 where you temp solder tack on the very end of that wire to its pin 6.
::
::
::Upon power up and retesting . . .if you are now being flooded with incoming stronger stations . . . . you need to look back into the internal fine wire connections of that IF transformer windings primary, yet again, ever so more closely.
::
::
::
::
::
::
::
::73's de Edd
::
::
::
::
::
::
::
::
::
:::Will do, Thanx Warren will check the tube tomorrow and then the coil.
:::
:::My cartridge is a Shure P90S
:::
:::
::
::
:::
::::In another post ( GE VRII cartridge ) Jerry has said he has 1000 needles and cartridges. May ask if he has a replacement for your phonograph.
::::
:::
:::
::
::
:
:
To remove those loctal tubes rock them towards the bump on the sides. They normally will pop right out then.
:For an easy test to see if the oscillator is working, take a transistor radio tuned to a blank spot somewhere in the middle of the dial. Put this radio close to the non working radio. Now turn the non working radios tuner back and forth around the same area in the middle of the dial that the working radio is tuned. If the oscillator in the non working set is working you will hear a noise from the working radio.
:To remove those loctal tubes rock them towards the bump on the sides. They normally will pop right out then.
:
:
:
:
:
::For an easy test to see if the oscillator is working, take a transistor radio tuned to a blank spot somewhere in the middle of the dial. Put this radio close to the non working radio. Now turn the non working radios tuner back and forth around the same area in the middle of the dial that the working radio is tuned. If the oscillator in the non working set is working you will hear a noise from the working radio.
::To remove those loctal tubes rock them towards the bump on the sides. They normally will pop right out then.
::
:
:
T.
:Agree with Thomas about that. Tune the radio to a known station that should be there. Adjust the timmer capacitor for the coil you re-wound. This being the 2nd IF transformer it's the detector one. If it's out of alignment there's no AF to detect from the RF.
:
I have a 7H7 there is that a swappable tube for he 7C7? It does not include it in the cross Reference. COuld that be it?
Also when you look at the tube drawing on this page it has an tab with an S between filament 1 and 7 tab. What is this tab?
:Nothing yet. I tried adjusting and nothing no crackles or anything sounding remotely close to stations. I am going to trace the signal path from the antenna back.
:
:
:
::Agree with Thomas about that. Tune the radio to a known station that should be there. Adjust the timmer capacitor for the coil you re-wound. This being the 2nd IF transformer it's the detector one. If it's out of alignment there's no AF to detect from the RF.
::
:
:
:
:I have a 7H7 there is that a swappable tube for he 7C7? It does not include it in the cross Reference. COuld that be it?
:
:Also when you look at the tube drawing on this page it has an tab with an S between filament 1 and 7 tab. What is this tab?
Bubba,
A 7C7 is a sharp cutoff pentode while the 7H7 is a semi-remote cutoff pentode. The 7H7 may work but is not a preferred substitute for the 7C7. The preferred sub is a 7B7. The tech. characteristics are different for the two...the 7C7 draws 150 ma filament current versus 300 ma for the 7H7, etc. Are you sure the existing subbed tube is a 7H7 as a 7AH7 or 7A7 are possible subs for a 7C7?
The S is simply the metal stub or guide stub for the loctal tube. John
I found a 7B7 and put it in but I still have nothing as far as Radio at all.. Any recomendations on how I can troubleshoot the Radio Signal portion? Can I inject a signal somwhere? This Sunday I am going to go out to a place that has RF Generators. I know the Osc is working now though.
::I notice the first tube is supposed to be a 7c7..
::
::I have a 7H7 there is that a swappable tube for he 7C7? It does not include it in the cross Reference. COuld that be it?
::
::Also when you look at the tube drawing on this page it has an tab with an S between filament 1 and 7 tab. What is this tab?
:
:Bubba,
:A 7C7 is a sharp cutoff pentode while the 7H7 is a semi-remote cutoff pentode. The 7H7 may work but is not a preferred substitute for the 7C7. The preferred sub is a 7B7. The tech. characteristics are different for the two...the 7C7 draws 150 ma filament current versus 300 ma for the 7H7, etc. Are you sure the existing subbed tube is a 7H7 as a 7AH7 or 7A7 are possible subs for a 7C7?
:The S is simply the metal stub or guide stub for the loctal tube. John
:
The 7C6 has 3 tests on a tube tester. did you test the 2 diodes section ? Do you know how to use a (RF) signal tracer?
I know how to use a signal tracer but I am not sure what frequencies to set it to and where to inject and how to look for the signal. I have no scope.
:Have you changed any of the old paper and wax capacitors?
:The 7C6 has 3 tests on a tube tester. did you test the 2 diodes section ? Do you know how to use a (RF) signal tracer?
:
Bubba
:Did you mean a signal generator? A signal tracer normally has no frequency settings. If you do have just a signal generator, try to do the 455KC I.F. alignment as said by the service information. If the radio does not pass any signal, you can use the signal generator like a signal injector. Use a .01 capacitor in series with the probe tip. The 455 KC (modulated) can be injected to pin 6 of the 7C6-7B7-7A8-7C7 in that order working backwards to the front end. Where you loose the signal that’s the problem stage.
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:Thanx Warren I will have access to one this weekend.
:
:Bubba
:
:
:
::Did you mean a signal generator? A signal tracer normally has no frequency settings. If you do have just a signal generator, try to do the 455KC I.F. alignment as said by the service information. If the radio does not pass any signal, you can use the signal generator like a signal injector. Use a .01 capacitor in series with the probe tip. The 455 KC (modulated) can be injected to pin 6 of the 7C6-7B7-7A8-7C7 in that order working backwards to the front end. Where you loose the signal that’s the problem stage.
::
::
::
::
::
::
::
::
::
::
::
::
::
::
::
::
:
:
It is frustrating because it WAS open but now that it is repaired and I have the plate voltage I still cannot get any audio out of the damn thing. I am taking it to the Radio museum tomorrow and they have signal generators. I also traced the antenna from the outside to Pin 6. It all checks out. It's damn frustrating. I have never seen a radio with good volages, working oscillator yet no stations. I can't figure it out. Oh well with signal generator in hand I should be able to narrow it down to a stage.
:The 2nd I.F. transformer for your Philco is of a particular design. It has inside the can ( dotted lines on the schematic ) Two capacitors and a resistor. ( Not counting the trimmers ) However this same 2nd I.F. can is used in many other models of Philco. 49-500 48-460 and PT-93 for example. If you feel you are not able to salvage the original, there is still plenty of parts sets and Junker chassis available. White wire to green wire should be 47K + 20 = 47,020 resistance.
:
:
http://www.radioremembered.org/
drone_chord0@hotmail.com
:Even though all voltages seem to be okay, you can still have no reception due to a single bad component. Check this link for some trouble shooting tips. It does go step by step with a 6 tube radio. The circuitry works just like your radio.
:
:http://www.radioremembered.org/
:
Before concluding that the IF can is bad you may want to try Warren's idea of the 10K resistor and gimik wire.
If that IF really is bad, you will get to hear your radio. I am sure that would be worth the trip in and of itself.
Best Regards,
Bill Grimm
OK trying it. I'll try anything at this point. Any other suggestion will be tried also. I am a phone tech and I have a little signal generator audio freq of course. When I attach it to the white wire of the can it comes throgh the speaker. I am just about to moe it to the green with a cap on it of course.
:Hi Bubba,
: Before concluding that the IF can is bad you may want to try Warren's idea of the 10K resistor and gimik wire.
: If that IF really is bad, you will get to hear your radio. I am sure that would be worth the trip in and of itself.
:
:Best Regards,
:Bill Grimm
:
:
:OK trying it. I'll try anything at this point. Any other suggestion will be tried also. I am a phone tech and I have a little signal generator audio freq of course. When I attach it to the white wire of the can it comes throgh the speaker. I am just about to moe it to the green with a cap on it of course.
:
:
:
:
:
:
:
::Hi Bubba,
:: Before concluding that the IF can is bad you may want to try Warren's idea of the 10K resistor and gimik wire.
:: If that IF really is bad, you will get to hear your radio. I am sure that would be worth the trip in and of itself.
::
::Best Regards,
::Bill Grimm
::
:
:
If you just want to get the radio working and you have a bad IF transformer .. you can by-pass it temporarily or permanently by following the simple steps in this article written by Norm Leal:
http://www.antiqueradios.com/chrs/journal/transformers.html
:Bubba:
:If you just want to get the radio working and you have a bad IF transformer .. you can by-pass it temporarily or permanently by following the simple steps in this article written by Norm Leal:
:http://www.antiqueradios.com/chrs/journal/transformers.html
:
:
:You can certainly try the capacitor bypass trick. ( kind of already did that with the gimik wire ) Since the coil is not open you won’t need the resistor. The voltages you gave for the negative AVC does indicate a non working radio. Replace C-21 100 Pf and C-12 .05 Mfd.
:
:
:Yes, put everything back as it all should be. At this point you are going around in circles. Basically restart trouble shooting. The AVC voltage says "Not Working" Lack of signal. From the 7C7 RF tube, and the rest of the RF chain. Everything is in and out. In pin 6, out pin 2. Somewhere along this chain there just about has to be an open, or leak to ground.
:
:
:
::Yes, put everything back as it all should be. At this point you are going around in circles. Basically restart trouble shooting. The AVC voltage says "Not Working" Lack of signal. From the 7C7 RF tube, and the rest of the RF chain. Everything is in and out. In pin 6, out pin 2. Somewhere along this chain there just about has to be an open, or leak to ground.
::
:
:
THX
:Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
:
I need to get some proper test equipment.
:I am going ot try it what size of cap should I use?
:
:THX
:
:
:
::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
::
:
:
:
:I need to get some proper test equipment.
:
:
:
::I am going ot try it what size of cap should I use?
::
::THX
::
::
::
:::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
:::
::
::
:
:
Hi Bubba,
Warren has been giving great advice, however, I would not have removed the gimmik wire. Your test does not exonerate the IF can.
Moreover, the way you are struggling here indicates there are two problems. One of them could be that IF can.
How does that other IF can look?
Just think how great it will sound when you get it working!
Best Regards,
Bill
Best R
::The jumpering Pin 6 thing with cap in the middle together didn't work I don't have a germanium diode. I have silicon though.
::
::I need to get some proper test equipment.
::
::
::
:::I am going ot try it what size of cap should I use?
:::
:::THX
:::
:::
:::
::::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
::::
:::
:::
::
::
:Hi Bubba,
: Warren has been giving great advice, however, I would not have removed the gimmik wire. Your test does not exonerate the IF can.
: Moreover, the way you are struggling here indicates there are two problems. One of them could be that IF can.
: How does that other IF can look?
: Just think how great it will sound when you get it working!
:
:Best Regards,
:
:Bill
:
:Best R
:
I am not sure what next to try though to get a sation out of this thing. I guess I might have to find someone with a scope and AC Generator.
:
:
:
:::The jumpering Pin 6 thing with cap in the middle together didn't work I don't have a germanium diode. I have silicon though.
:::
:::I need to get some proper test equipment.
:::
:::
:::
::::I am going ot try it what size of cap should I use?
::::
::::THX
::::
::::
::::
:::::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
:::::
::::
::::
:::
:::
::Hi Bubba,
:: Warren has been giving great advice, however, I would not have removed the gimmik wire. Your test does not exonerate the IF can.
:: Moreover, the way you are struggling here indicates there are two problems. One of them could be that IF can.
:: How does that other IF can look?
:: Just think how great it will sound when you get it working!
::
::Best Regards,
::
::Bill
::
::Best R
::
:
:
:
:I am not sure what next to try though to get a sation out of this thing. I guess I might have to find someone with a scope and AC Generator.
:
:
::
::
::
::::The jumpering Pin 6 thing with cap in the middle together didn't work I don't have a germanium diode. I have silicon though.
::::
::::I need to get some proper test equipment.
::::
::::
::::
:::::I am going ot try it what size of cap should I use?
:::::
:::::THX
:::::
:::::
:::::
::::::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
::::::
:::::
:::::
::::
::::
:::Hi Bubba,
::: Warren has been giving great advice, however, I would not have removed the gimmik wire. Your test does not exonerate the IF can.
::: Moreover, the way you are struggling here indicates there are two problems. One of them could be that IF can.
::: How does that other IF can look?
::: Just think how great it will sound when you get it working!
:::
:::Best Regards,
:::
:::Bill
:::
:::Best R
:::
::
::
:
:
Hi Bubba,
It seems like we have centered down on the problem(s) being in the IF, although the RF input hasn't been verified. Your oscilator seems to be OK.
Without a signal generator, your options are limited.
You may want to consider trying a capacitor around the first IF can. You may have a coupling problem there, too.
Even if you get sound out of the radio, you will need a signal generator to align it properly. Era tuning with a radio station may get you close, but performance will not likely be great.
Let's see how that second capacitor does.
All the Best,
Bill
::
::I am not sure what next to try though to get a sation out of this thing. I guess I might have to find someone with a scope and AC Generator.
::
::
:::
:::
:::
:::::The jumpering Pin 6 thing with cap in the middle together didn't work I don't have a germanium diode. I have silicon though.
:::::
:::::I need to get some proper test equipment.
:::::
:::::
:::::
::::::I am going ot try it what size of cap should I use?
::::::
::::::THX
::::::
::::::
::::::
:::::::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
:::::::
::::::
::::::
:::::
:::::
::::Hi Bubba,
:::: Warren has been giving great advice, however, I would not have removed the gimmik wire. Your test does not exonerate the IF can.
:::: Moreover, the way you are struggling here indicates there are two problems. One of them could be that IF can.
:::: How does that other IF can look?
:::: Just think how great it will sound when you get it working!
::::
::::Best Regards,
::::
::::Bill
::::
::::Best R
::::
:::
:::
::
::
:Hi Bubba,
: It seems like we have centered down on the problem(s) being in the IF, although the RF input hasn't been verified. Your oscilator seems to be OK.
: Without a signal generator, your options are limited.
: You may want to consider trying a capacitor around the first IF can. You may have a coupling problem there, too.
:
: Even if you get sound out of the radio, you will need a signal generator to align it properly. Era tuning with a radio station may get you close, but performance will not likely be great.
:
: Let's see how that second capacitor does.
:
:All the Best,
:
:Bill
:
Can I use a 1n4005 Diode for the signal tracer? I do not have a germanium diode.
Bubba
:Wow Bubba, this has to be one of the longest threads in history. A silicon diode won't work for a detector. The voltage table you posted before, does indicate the primaries of the RF coil, and both IF primaries are fine. The secondaries all seem to have the proper resistance as you have checked. Sometimes it's the most simple of things just overlooked. Like the tuner large gangs shorting to each other. That would kill any signal to the RF tube. A signal generator or at least a signal tracer would narrow down the problem. Without anything to make, or trace a signal you are really just beating a dead horse sort of speak.
:
It is very odd that the can was open and also that there may be other problems in the RF. Also there was a defective Crystal Cartridge. Very Odd that there could be so many things wrong, but I guess stranger things have happened. I did the resistance reading with the service notes and ALL resiatances are correct on all pins on all tubes..
Now I just need to find someone here in Vancouver with a scope and a generator. Funny that I do not know anyone who has one after going through tech school. I had both a few years ago but sold it. Thanx to EVERYONE for their very generous help.
:C-3 (large gangs) is the antenna tuner. C-1 (small gangs) are the oscillator tuning (working) The moving gangs are grounded to the chassis. It's the stationary part that is not. Remove (green wire) antenna loop. Measure from side terminal on antenna side (large gangs) to chassis ground. Normally a visual inspection you could see if the gangs are touching each other.
:
Here's another trick you might try. It's a bit more risky, as it involves two radios connected together.
Take another radio that uses 455KC IF transformers. The radio should preferrably be AC.
Observe chassis ground for both radios. See to it that both radios are plugged in so that the chassis connects to the common return of the AC line. Connect a .05 MFD capacitor from one radio's chassis to the other. Take the 2nd IF transformer secondary lead of the good working radio that connects to the volume control (either directly, or through a resistor), and connect it to the volume control of the non-working radio where the IF transformer secondary of the non-working radio would connect (disconnect it). Turn on both the working and the non-working radios and adjust the volume control of the non-working radio and listen for stations. Tune the working radio.
Once you have verified that the amplifier of the non-working radio is working, reconnect its 2nd IF secondary as it was originally connected. Disconnect the primary of its 2nd IF transformer from the plate of the IF tube and B+. Connect it instead to the plate of the IF tube and B+ of the working radio, and disconnect the 2nd IF transformer of the working radio from these points. Listen in the non-working radio again for stations. Adjust the non-working radio's IF transformer until stations can be heard. Reconnect it to the non-working radio's IF tube. Repeat for the non-working radio's 1st IF transformer.
By now you should have the IF circuitry roughly adjusted, and the non-working radio should now be working on its own. If not, then you still have some trouble in the front end, which isn't so difficult to work with.
T.
T.
|
:Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:
:T.
:
THX Ed...
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba . . . . .
:
:
:What wrong you . . . you no give up now !.
:
:
:Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:
:
:OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:
:
:Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:
:
:Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:
:
:I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:
:
:It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:
:
:The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:
:
:We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:
:
:Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:
:
:Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:
:
:Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:
:
:If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:
:
:Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:
:
:Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:
:
:
:
:
:
:
:Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::
::T.
::
:
:
Are they built into the ceramic top of the can?
Just curious. The dotted lines indicat that they are inside the can.. I see nothing.
:Heh your ideas are always entertaining. I will do it tonight. i have both transistor and other tube radios... I could by a scope and RF Gen again but I really don't want to. It's not the money it's the storage and so rarely does one need them for repairing a radio. In a few days I will go out to the radio museum again S.P.A.R.C and try again on Sunday if I can find some working radio equipment in that joint...
:
:THX Ed...
:
:
:
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Bubba . . . . .
::
::
::What wrong you . . . you no give up now !.
::
::
::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::
::
::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::
::
::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::
::
::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::
::
::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::
::
::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::
::
::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::
::
::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::
::
::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::
::
::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::
::
::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::
::
::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::
::
::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::
::
::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::
::
::
::
::
::
::
::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::
::
::73's de Edd
::
::
::
::
::
::
::
::
::
:::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::
:::T.
:::
::
::
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba . . . . .
:
:
:What wrong you . . . you no give up now !.
:
:
:Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:
:
:OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:
:
:Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:
:
:Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:
:
:I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:
:
:It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:
:
:The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:
:
:We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:
:
:Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:
:
:Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:
:
:Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:
:
:If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:
:
:Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:
:
:Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:
:
:
:
:
:
:
:Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::
::T.
::
:
:
And the green wire out of the can to pin 6 of the 7C6 also.
:OK both on the Mixer and the IF. The Transistor chirped like a bird when I went up and down the dial on the Philco but I had your resistor trick in place when I did it. I am going to put back the wound can that I did and try it again. No stations out the Philco speaker though. I assume that my oscillator and tuner is working. I just cannot get audio out the speaker. other than the amplifier hum. WHen I put a small AC wave generator on the plate of the IF it does come out the amp though so prooving the amp is amplifying. Why is no station audio coming out the speaker though? OK on with the same experiment without the makeshift 10 K in place..
:
:
:
:
:
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Bubba . . . . .
::
::
::What wrong you . . . you no give up now !.
::
::
::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::
::
::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::
::
::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::
::
::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::
::
::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::
::
::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::
::
::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::
::
::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::
::
::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::
::
::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::
::
::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::
::
::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::
::
::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::
::
::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::
::
::
::
::
::
::
::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::
::
::73's de Edd
::
::
::
::
::
::
::
::
::
:::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::
:::T.
:::
::
::
:
:
:The transistor radio is being used as a make shift signal tracer. There would be no audio from the Philco like this. With the connection to the mixer tube, the transistor radio should have picked up a station tuned by the Philco. What this does seem to indicate is that the problem is before the IF. T6 would be the likely suspect. There are two 30 ohm coils with resistors across them. A 15K and a 6.8K .. 15,000 divided by 30 =500 ohms. 6800 divided by 30 = 226
:
Is the divided by formula you did another type of calculation?
:T6....Across the Primary 6.8K and 30 ohm coil in parralel reads 31.5 ohms on the Red Blue wires. The secondary of T6 unlike the schematic has no 15k in parralel with the coil, only the coil and it also reads 30 ohms on the White Green wires.. Both sides are making it to their respective destinations.
:
:
:
::The transistor radio is being used as a make shift signal tracer. There would be no audio from the Philco like this. With the connection to the mixer tube, the transistor radio should have picked up a station tuned by the Philco. What this does seem to indicate is that the problem is before the IF. T6 would be the likely suspect. There are two 30 ohm coils with resistors across them. A 15K and a 6.8K .. 15,000 divided by 30 =500 ohms. 6800 divided by 30 = 226
::
:
:
Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba . . . . .
:
:
:What wrong you . . . you no give up now !.
:
:
:Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:
:
:OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:
:
:Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:
:
:Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:
:
:I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:
:
:It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:
:
:The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:
:
:We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:
:
:Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:
:
:Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:
:
:Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:
:
:If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:
:
:Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:
:
:Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:
:
:
:
:
:
:
:Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::
::T.
::
:
:
:i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
:
:Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:
:
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Bubba . . . . .
::
::
::What wrong you . . . you no give up now !.
::
::
::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::
::
::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::
::
::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::
::
::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::
::
::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::
::
::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::
::
::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::
::
::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::
::
::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::
::
::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::
::
::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::
::
::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::
::
::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::
::
::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::
::
::
::
::
::
::
::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::
::
::73's de Edd
::
::
::
::
::
::
::
::
::
:::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::
:::T.
:::
::
::
:
:
|
:OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
:
:
:
:
:
::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
::
::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
::
::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::Sir Bubba . . . . .
:::
:::
:::What wrong you . . . you no give up now !.
:::
:::
:::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:::
:::
:::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:::
:::
:::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:::
:::
:::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:::
:::
:::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:::
:::
:::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:::
:::
:::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:::
:::
:::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:::
:::
:::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:::
:::
:::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:::
:::
:::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:::
:::
:::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:::
:::
:::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:::
:::
:::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:::
:::
:::
:::
:::
:::
:::
:::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:::
:::
:::73's de Edd
:::
:::
:::
:::
:::
:::
:::
:::
:::
::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::::
::::T.
::::
:::
:::
::
::
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba . . . . .
:
:
:One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
:
:
:Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
:
:
:Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
:
:
:You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
:
:
:Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
:
:
:That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
:
:
:BTW . . .
:
:
:Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
:
:
:
:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
::
::
::
::
::
:::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
:::
:::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:::
:::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::Sir Bubba . . . . .
::::
::::
::::What wrong you . . . you no give up now !.
::::
::::
::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::::
::::
::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::::
::::
::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::::
::::
::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::::
::::
::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::::
::::
::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::::
::::
::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::::
::::
::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::::
::::
::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::::
::::
::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::::
::::
::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::::
::::
::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::::
::::
::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::::
::::
::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::::
::::
::::
::::
::::
::::
::::
::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::::
::::
::::73's de Edd
::::
::::
::::
::::
::::
::::
::::
::::
::::
:::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::::
:::::T.
:::::
::::
::::
:::
:::
::
::
:
:
:Will do all. THX ED.
:
:
:
:
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Bubba . . . . .
::
::
::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
::
::
::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
::
::
::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
::
::
::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
::
::
::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
::
::
::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
::
::
::BTW . . .
::
::
::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
::
::
::
::
::
::
::
::
::
::73's de Edd
::
::
::
::
::
::
::
::
::
:::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
:::
:::
:::
:::
:::
::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
::::
::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
::::
::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::Sir Bubba . . . . .
:::::
:::::
:::::What wrong you . . . you no give up now !.
:::::
:::::
:::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:::::
:::::
:::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:::::
:::::
:::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:::::
:::::
:::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:::::
:::::
:::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:::::
:::::
:::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:::::
:::::
:::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:::::
:::::
:::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:::::
:::::
:::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:::::
:::::
:::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:::::
:::::
:::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:::::
:::::
:::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:::::
:::::
:::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:::::
:::::
:::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:::::
:::::
:::::73's de Edd
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::::::
::::::T.
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
:
:
:
:
:
:
::Will do all. THX ED.
::
::
::
::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::Sir Bubba . . . . .
:::
:::
:::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
:::
:::
:::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
:::
:::
:::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
:::
:::
:::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
:::
:::
:::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
:::
:::
:::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
:::
:::
:::BTW . . .
:::
:::
:::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::73's de Edd
:::
:::
:::
:::
:::
:::
:::
:::
:::
::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
::::
::::
::::
::::
::::
:::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
:::::
:::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:::::
:::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::Sir Bubba . . . . .
::::::
::::::
::::::What wrong you . . . you no give up now !.
::::::
::::::
::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::::::
::::::
::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::::::
::::::
::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::::::
::::::
::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::::::
::::::
::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::::::
::::::
::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::::::
::::::
::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::::::
::::::
::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::::::
::::::
::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::::::
::::::
::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::::::
::::::
::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::::::
::::::
::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::::::
::::::
::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::::::
::::::
::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::::::
::::::
::::::73's de Edd
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
:::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::::::
:::::::T.
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
If it still works the same, you have NOW confirmed the RF amplification / passage capabilities of that tube which was being used in the IF stage previously, so the one in the IF stage should be a good tube. Don’t you worry . . . never fear . . .we almost gettin’ near . . . a solution to the query ! |
::OK Ed I got a station CBC likely the strongest signal out of the transistor when jumper from Philco is on pin 2 of 7A8 Conv tube. When I tune the Philco away it goes away, when I tune it, it's definatly there and being produced by the Phico. Does this prove that everything before and mailny the variable tuner is good? ie 7c7 and 7a8 stages? I moved the jumper to the 7b7 2nd IF tube pin 2 and I get nothing.. I also get nothing on the Grid pin 6 of the 7B7 however the resistance through primary and 2ndary and all circuitry around t1 first IF seems right.
:
:
::
::
::
::
::
::
:::Will do all. THX ED.
:::
:::
:::
:::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::Sir Bubba . . . . .
::::
::::
::::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
::::
::::
::::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
::::
::::
::::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
::::
::::
::::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
::::
::::
::::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
::::
::::
::::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
::::
::::
::::BTW . . .
::::
::::
::::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::73's de Edd
::::
::::
::::
::::
::::
::::
::::
::::
::::
:::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
:::::
:::::
:::::
:::::
:::::
::::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
::::::
::::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
::::::
::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::Sir Bubba . . . . .
:::::::
:::::::
:::::::What wrong you . . . you no give up now !.
:::::::
:::::::
:::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:::::::
:::::::
:::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:::::::
:::::::
:::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:::::::
:::::::
:::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:::::::
:::::::
:::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:::::::
:::::::
:::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:::::::
:::::::
:::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:::::::
:::::::
:::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:::::::
:::::::
:::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:::::::
:::::::
:::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:::::::
:::::::
:::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:::::::
:::::::
:::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:::::::
:::::::
:::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:::::::
:::::::
:::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:::::::
:::::::
:::::::73's de Edd
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
::::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::::::::
::::::::T.
::::::::
:::::::
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
Thanx for all your help and the others too.. I am learning radio stages again since school I have done telecom for so many years one forget's..
I will go out to the Radio club tomorrow and see if I can get another RF Amp after my test...
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba. . . . .
:
:
:yes . . . yes . . .YES . . .your findings are indicative of a functioning RF amplifier stage along with the Mixer stage.
:
:
:And with no equal or really . . . A STRONGER . . . output being experienced when you transfer the clip over to the plate (Pin 2 ) of the IF amp, that then is being indicative of SOME fallacy within your IF amp stage.
:
:
:You then might swap out the IF amp tube and the RF tube and test the output out from the mixer again, since it was working and passing signal just before.
:
: If it still works the same, you have NOW confirmed the RF amplification / passage capabilities of that tube which was being used in the IF stage previously, so the one in the IF stage should be a good tube.
:
:
:Now do a test again at the plate (pin 2)of the IF amp using the now criss-crossed "good" tubes.
:
:
:Confirm the plate and screen voltages of the IF amp along with measuring its cathode (pin 7) resistance over to pins 4 and 5 for ~0 ohms to confirm that your Phono/Radio switch is not having its antiquated contacts . . . oxide floating.
:
:
:If one ends up having to replace that Second If transformer, it is not etched in stone that you HAVE to use that identical type of electrically constructed one with its built in Pi network R/C elements which are serving as an initial RF and then a hi AF frequency “tweet” filter.
:Specifically . . . one could use a conventional two winding four lead IF transformer and then mount/wire the two 100 Pf and one 47 k resistor externally and right off the bottom right IF transformers corner terminal lug.
:
:
:For testing and evaluative purposes one could use just about ANY 455 transformer which you have on hand or could temporarily borrow or cannibalize. (the Tweet filter network also doesn’t have to be in circuit either.)
:
:
:
:Don’t you worry . . . never fear . . .we almost gettin’ near . . . a solution to the query !
:
:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
:
:::OK Ed I got a station CBC likely the strongest signal out of the transistor when jumper from Philco is on pin 2 of 7A8 Conv tube. When I tune the Philco away it goes away, when I tune it, it's definatly there and being produced by the Phico. Does this prove that everything before and mailny the variable tuner is good? ie 7c7 and 7a8 stages? I moved the jumper to the 7b7 2nd IF tube pin 2 and I get nothing.. I also get nothing on the Grid pin 6 of the 7B7 however the resistance through primary and 2ndary and all circuitry around t1 first IF seems right.
::
::
:::
:::
:::
:::
:::
:::
::::Will do all. THX ED.
::::
::::
::::
::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::Sir Bubba . . . . .
:::::
:::::
:::::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
:::::
:::::
:::::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
:::::
:::::
:::::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
:::::
:::::
:::::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
:::::
:::::
:::::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
:::::
:::::
:::::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
:::::
:::::
:::::BTW . . .
:::::
:::::
:::::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::73's de Edd
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
::::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
::::::
::::::
::::::
::::::
::::::
:::::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
:::::::
:::::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:::::::
:::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::Sir Bubba . . . . .
::::::::
::::::::
::::::::What wrong you . . . you no give up now !.
::::::::
::::::::
::::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::::::::
::::::::
::::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::::::::
::::::::
::::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::::::::
::::::::
::::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::::::::
::::::::
::::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::::::::
::::::::
::::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::::::::
::::::::
::::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::::::::
::::::::
::::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::::::::
::::::::
::::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::::::::
::::::::
::::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::::::::
::::::::
::::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::::::::
::::::::
::::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::::::::
::::::::
::::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::::::::
::::::::
::::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::::::::
::::::::
::::::::73's de Edd
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
:::::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::::::::
:::::::::T.
:::::::::
::::::::
::::::::
:::::::
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:Sir Bubba. . . . .
:
:
:yes . . . yes . . .YES . . .your findings are indicative of a functioning RF amplifier stage along with the Mixer stage.
:
:
:And with no equal or really . . . A STRONGER . . . output being experienced when you transfer the clip over to the plate (Pin 2 ) of the IF amp, that then is being indicative of SOME fallacy within your IF amp stage.
:
:
:You then might swap out the IF amp tube and the RF tube and test the output out from the mixer again, since it was working and passing signal just before.
:
: If it still works the same, you have NOW confirmed the RF amplification / passage capabilities of that tube which was being used in the IF stage previously, so the one in the IF stage should be a good tube.
:
:
:Now do a test again at the plate (pin 2)of the IF amp using the now criss-crossed "good" tubes.
:
:
:Confirm the plate and screen voltages of the IF amp along with measuring its cathode (pin 7) resistance over to pins 4 and 5 for ~0 ohms to confirm that your Phono/Radio switch is not having its antiquated contacts . . . oxide floating.
:
:
:If one ends up having to replace that Second If transformer, it is not etched in stone that you HAVE to use that identical type of electrically constructed one with its built in Pi network R/C elements which are serving as an initial RF and then a hi AF frequency “tweet” filter.
:Specifically . . . one could use a conventional two winding four lead IF transformer and then mount/wire the two 100 Pf and one 47 k resistor externally and right off the bottom right IF transformers corner terminal lug.
:
:
:For testing and evaluative purposes one could use just about ANY 455 transformer which you have on hand or could temporarily borrow or cannibalize. (the Tweet filter network also doesn’t have to be in circuit either.)
:
:
:
:Don’t you worry . . . never fear . . .we almost gettin’ near . . . a solution to the query !
:
:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
:
:
:
:
:
:::OK Ed I got a station CBC likely the strongest signal out of the transistor when jumper from Philco is on pin 2 of 7A8 Conv tube. When I tune the Philco away it goes away, when I tune it, it's definatly there and being produced by the Phico. Does this prove that everything before and mailny the variable tuner is good? ie 7c7 and 7a8 stages? I moved the jumper to the 7b7 2nd IF tube pin 2 and I get nothing.. I also get nothing on the Grid pin 6 of the 7B7 however the resistance through primary and 2ndary and all circuitry around t1 first IF seems right.
::
::
:::
:::
:::
:::
:::
:::
::::Will do all. THX ED.
::::
::::
::::
::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::Sir Bubba . . . . .
:::::
:::::
:::::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
:::::
:::::
:::::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
:::::
:::::
:::::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
:::::
:::::
:::::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
:::::
:::::
:::::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
:::::
:::::
:::::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
:::::
:::::
:::::BTW . . .
:::::
:::::
:::::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::73's de Edd
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
:::::
::::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
::::::
::::::
::::::
::::::
::::::
:::::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
:::::::
:::::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:::::::
:::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::Sir Bubba . . . . .
::::::::
::::::::
::::::::What wrong you . . . you no give up now !.
::::::::
::::::::
::::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::::::::
::::::::
::::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::::::::
::::::::
::::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::::::::
::::::::
::::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::::::::
::::::::
::::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::::::::
::::::::
::::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::::::::
::::::::
::::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::::::::
::::::::
::::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::::::::
::::::::
::::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::::::::
::::::::
::::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::::::::
::::::::
::::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::::::::
::::::::
::::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::::::::
::::::::
::::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::::::::
::::::::
::::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::::::::
::::::::
::::::::73's de Edd
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
:::::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::::::::
:::::::::T.
:::::::::
::::::::
::::::::
:::::::
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
Damn.. How much time did that burn.
My hand wound IF coil then worked. I tuned the entire radio by ear. That is pretty easy...
I am going to replace the coil anyway though.
I got about 6 from the museam around 20 ohms.
THanx to all. That is the last time I replace tubes with subs without trying the original also.
Bubba
:I tried swapping the IF and RF tubes and does not work when I do that, but I then took another tested good 7H7 and put it in place of the 7H7 that I swapped.. It also did not work. For some reason this radio does not seem to like 7H7s even though it sayd they are a substitute.. It works with the 7B7s though. I do not have any Xtra 7B7s or 7C7s,, so I will go to the Museum and use the tubes stated on the schem.. Aren't 7H7s just higher gain?
:
:
:
:
::
::
::
::
::
::
::
::
::
::
::
::
::
::
::Sir Bubba. . . . .
::
::
::yes . . . yes . . .YES . . .your findings are indicative of a functioning RF amplifier stage along with the Mixer stage.
::
::
::And with no equal or really . . . A STRONGER . . . output being experienced when you transfer the clip over to the plate (Pin 2 ) of the IF amp, that then is being indicative of SOME fallacy within your IF amp stage.
::
::
::You then might swap out the IF amp tube and the RF tube and test the output out from the mixer again, since it was working and passing signal just before.
::
:: If it still works the same, you have NOW confirmed the RF amplification / passage capabilities of that tube which was being used in the IF stage previously, so the one in the IF stage should be a good tube.
::
::
::Now do a test again at the plate (pin 2)of the IF amp using the now criss-crossed "good" tubes.
::
::
::Confirm the plate and screen voltages of the IF amp along with measuring its cathode (pin 7) resistance over to pins 4 and 5 for ~0 ohms to confirm that your Phono/Radio switch is not having its antiquated contacts . . . oxide floating.
::
::
::If one ends up having to replace that Second If transformer, it is not etched in stone that you HAVE to use that identical type of electrically constructed one with its built in Pi network R/C elements which are serving as an initial RF and then a hi AF frequency “tweet” filter.
::Specifically . . . one could use a conventional two winding four lead IF transformer and then mount/wire the two 100 Pf and one 47 k resistor externally and right off the bottom right IF transformers corner terminal lug.
::
::
::For testing and evaluative purposes one could use just about ANY 455 transformer which you have on hand or could temporarily borrow or cannibalize. (the Tweet filter network also doesn’t have to be in circuit either.)
::
::
::
::Don’t you worry . . . never fear . . .we almost gettin’ near . . . a solution to the query !
::
::
::
::
::
::
::
::73's de Edd
::
::
::
::
::
::
::
::
::
::
::::OK Ed I got a station CBC likely the strongest signal out of the transistor when jumper from Philco is on pin 2 of 7A8 Conv tube. When I tune the Philco away it goes away, when I tune it, it's definatly there and being produced by the Phico. Does this prove that everything before and mailny the variable tuner is good? ie 7c7 and 7a8 stages? I moved the jumper to the 7b7 2nd IF tube pin 2 and I get nothing.. I also get nothing on the Grid pin 6 of the 7B7 however the resistance through primary and 2ndary and all circuitry around t1 first IF seems right.
:::
:::
::::
::::
::::
::::
::::
::::
:::::Will do all. THX ED.
:::::
:::::
:::::
:::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::Sir Bubba . . . . .
::::::
::::::
::::::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
::::::
::::::
::::::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
::::::
::::::
::::::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
::::::
::::::
::::::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
::::::
::::::
::::::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
::::::
::::::
::::::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
::::::
::::::
::::::BTW . . .
::::::
::::::
::::::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::73's de Edd
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
::::::
:::::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
:::::::
:::::::
:::::::
:::::::
:::::::
::::::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
::::::::
::::::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
::::::::
::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::Sir Bubba . . . . .
:::::::::
:::::::::
:::::::::What wrong you . . . you no give up now !.
:::::::::
:::::::::
:::::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:::::::::
:::::::::
:::::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:::::::::
:::::::::
:::::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:::::::::
:::::::::
:::::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:::::::::
:::::::::
:::::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:::::::::
:::::::::
:::::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:::::::::
:::::::::
:::::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:::::::::
:::::::::
:::::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:::::::::
:::::::::
:::::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:::::::::
:::::::::
:::::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:::::::::
:::::::::
:::::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:::::::::
:::::::::
:::::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:::::::::
:::::::::
:::::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:::::::::
:::::::::
:::::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:::::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:::::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:::::::::
:::::::::
:::::::::73's de Edd
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
::::::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::::::::::
::::::::::T.
::::::::::
:::::::::
:::::::::
::::::::
::::::::
:::::::
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
THX
:It was using a (good I might add) 7H7 in place of a 7C7 or 7B7.. apparently they are not a direct replacments even though the tube cross reference on this page says they are.
:
:Damn.. How much time did that burn.
:
:My hand wound IF coil then worked. I tuned the entire radio by ear. That is pretty easy...
:
:I am going to replace the coil anyway though.
:
:I got about 6 from the museam around 20 ohms.
:
:THanx to all. That is the last time I replace tubes with subs without trying the original also.
:
:Bubba
:
:
:
:
::I tried swapping the IF and RF tubes and does not work when I do that, but I then took another tested good 7H7 and put it in place of the 7H7 that I swapped.. It also did not work. For some reason this radio does not seem to like 7H7s even though it sayd they are a substitute.. It works with the 7B7s though. I do not have any Xtra 7B7s or 7C7s,, so I will go to the Museum and use the tubes stated on the schem.. Aren't 7H7s just higher gain?
::
::
::
::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::Sir Bubba. . . . .
:::
:::
:::yes . . . yes . . .YES . . .your findings are indicative of a functioning RF amplifier stage along with the Mixer stage.
:::
:::
:::And with no equal or really . . . A STRONGER . . . output being experienced when you transfer the clip over to the plate (Pin 2 ) of the IF amp, that then is being indicative of SOME fallacy within your IF amp stage.
:::
:::
:::You then might swap out the IF amp tube and the RF tube and test the output out from the mixer again, since it was working and passing signal just before.
:::
::: If it still works the same, you have NOW confirmed the RF amplification / passage capabilities of that tube which was being used in the IF stage previously, so the one in the IF stage should be a good tube.
:::
:::
:::Now do a test again at the plate (pin 2)of the IF amp using the now criss-crossed "good" tubes.
:::
:::
:::Confirm the plate and screen voltages of the IF amp along with measuring its cathode (pin 7) resistance over to pins 4 and 5 for ~0 ohms to confirm that your Phono/Radio switch is not having its antiquated contacts . . . oxide floating.
:::
:::
:::If one ends up having to replace that Second If transformer, it is not etched in stone that you HAVE to use that identical type of electrically constructed one with its built in Pi network R/C elements which are serving as an initial RF and then a hi AF frequency “tweet” filter.
:::Specifically . . . one could use a conventional two winding four lead IF transformer and then mount/wire the two 100 Pf and one 47 k resistor externally and right off the bottom right IF transformers corner terminal lug.
:::
:::
:::For testing and evaluative purposes one could use just about ANY 455 transformer which you have on hand or could temporarily borrow or cannibalize. (the Tweet filter network also doesn’t have to be in circuit either.)
:::
:::
:::
:::Don’t you worry . . . never fear . . .we almost gettin’ near . . . a solution to the query !
:::
:::
:::
:::
:::
:::
:::
:::73's de Edd
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::::OK Ed I got a station CBC likely the strongest signal out of the transistor when jumper from Philco is on pin 2 of 7A8 Conv tube. When I tune the Philco away it goes away, when I tune it, it's definatly there and being produced by the Phico. Does this prove that everything before and mailny the variable tuner is good? ie 7c7 and 7a8 stages? I moved the jumper to the 7b7 2nd IF tube pin 2 and I get nothing.. I also get nothing on the Grid pin 6 of the 7B7 however the resistance through primary and 2ndary and all circuitry around t1 first IF seems right.
::::
::::
:::::
:::::
:::::
:::::
:::::
:::::
::::::Will do all. THX ED.
::::::
::::::
::::::
::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::Sir Bubba . . . . .
:::::::
:::::::
:::::::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
:::::::
:::::::
:::::::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
:::::::
:::::::
:::::::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
:::::::
:::::::
:::::::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
:::::::
:::::::
:::::::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
:::::::
:::::::
:::::::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
:::::::
:::::::
:::::::BTW . . .
:::::::
:::::::
:::::::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::73's de Edd
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
:::::::
::::::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
::::::::
::::::::
::::::::
::::::::
::::::::
:::::::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
:::::::::
:::::::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
:::::::::
:::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::Sir Bubba . . . . .
::::::::::
::::::::::
::::::::::What wrong you . . . you no give up now !.
::::::::::
::::::::::
::::::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
::::::::::
::::::::::
::::::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
::::::::::
::::::::::
::::::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
::::::::::
::::::::::
::::::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
::::::::::
::::::::::
::::::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
::::::::::
::::::::::
::::::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
::::::::::
::::::::::
::::::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
::::::::::
::::::::::
::::::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
::::::::::
::::::::::
::::::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
::::::::::
::::::::::
::::::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
::::::::::
::::::::::
::::::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
::::::::::
::::::::::
::::::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
::::::::::
::::::::::
::::::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
::::::::::
::::::::::
::::::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
::::::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
::::::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
::::::::::
::::::::::
::::::::::73's de Edd
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
::::::::::
:::::::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
:::::::::::
:::::::::::T.
:::::::::::
::::::::::
::::::::::
:::::::::
:::::::::
::::::::
::::::::
:::::::
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
Oh well. Anyone got a Philco IF transformer that will work?
:If I was to remove that 2 Capacitor 1 resistor network how would I do it. I am not sure circuit wise what to leave out and what needs to stay in? i tried bulding it and it is not working. I am getting One channel completely across the dial now.
:
:THX
:
:
:
:
::It was using a (good I might add) 7H7 in place of a 7C7 or 7B7.. apparently they are not a direct replacments even though the tube cross reference on this page says they are.
::
::Damn.. How much time did that burn.
::
::My hand wound IF coil then worked. I tuned the entire radio by ear. That is pretty easy...
::
::I am going to replace the coil anyway though.
::
::I got about 6 from the museam around 20 ohms.
::
::THanx to all. That is the last time I replace tubes with subs without trying the original also.
::
::Bubba
::
::
::
::
:::I tried swapping the IF and RF tubes and does not work when I do that, but I then took another tested good 7H7 and put it in place of the 7H7 that I swapped.. It also did not work. For some reason this radio does not seem to like 7H7s even though it sayd they are a substitute.. It works with the 7B7s though. I do not have any Xtra 7B7s or 7C7s,, so I will go to the Museum and use the tubes stated on the schem.. Aren't 7H7s just higher gain?
:::
:::
:::
:::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::Sir Bubba. . . . .
::::
::::
::::yes . . . yes . . .YES . . .your findings are indicative of a functioning RF amplifier stage along with the Mixer stage.
::::
::::
::::And with no equal or really . . . A STRONGER . . . output being experienced when you transfer the clip over to the plate (Pin 2 ) of the IF amp, that then is being indicative of SOME fallacy within your IF amp stage.
::::
::::
::::You then might swap out the IF amp tube and the RF tube and test the output out from the mixer again, since it was working and passing signal just before.
::::
:::: If it still works the same, you have NOW confirmed the RF amplification / passage capabilities of that tube which was being used in the IF stage previously, so the one in the IF stage should be a good tube.
::::
::::
::::Now do a test again at the plate (pin 2)of the IF amp using the now criss-crossed "good" tubes.
::::
::::
::::Confirm the plate and screen voltages of the IF amp along with measuring its cathode (pin 7) resistance over to pins 4 and 5 for ~0 ohms to confirm that your Phono/Radio switch is not having its antiquated contacts . . . oxide floating.
::::
::::
::::If one ends up having to replace that Second If transformer, it is not etched in stone that you HAVE to use that identical type of electrically constructed one with its built in Pi network R/C elements which are serving as an initial RF and then a hi AF frequency “tweet” filter.
::::Specifically . . . one could use a conventional two winding four lead IF transformer and then mount/wire the two 100 Pf and one 47 k resistor externally and right off the bottom right IF transformers corner terminal lug.
::::
::::
::::For testing and evaluative purposes one could use just about ANY 455 transformer which you have on hand or could temporarily borrow or cannibalize. (the Tweet filter network also doesn’t have to be in circuit either.)
::::
::::
::::
::::Don’t you worry . . . never fear . . .we almost gettin’ near . . . a solution to the query !
::::
::::
::::
::::
::::
::::
::::
::::73's de Edd
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::
::::::OK Ed I got a station CBC likely the strongest signal out of the transistor when jumper from Philco is on pin 2 of 7A8 Conv tube. When I tune the Philco away it goes away, when I tune it, it's definatly there and being produced by the Phico. Does this prove that everything before and mailny the variable tuner is good? ie 7c7 and 7a8 stages? I moved the jumper to the 7b7 2nd IF tube pin 2 and I get nothing.. I also get nothing on the Grid pin 6 of the 7B7 however the resistance through primary and 2ndary and all circuitry around t1 first IF seems right.
:::::
:::::
::::::
::::::
::::::
::::::
::::::
::::::
:::::::Will do all. THX ED.
:::::::
:::::::
:::::::
:::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::Sir Bubba . . . . .
::::::::
::::::::
::::::::One mo' time, then . . .You can have the Peelcos volume down to Zeeeeero . . . and no chance that you do not still have it in the phono positon . . right ?
::::::::
::::::::
::::::::Now if the vol-you-me is up on the Transistor "monitor" and you have its internal loop receiving the close proximity capacitance of the test lead connected to the plate of the Philcos mixer tube.
::::::::
::::::::
::::::::Additionally the Transistor must be tuned right on to 910 khz which is the second harmonic of the 455/6 signal originating at the plate of the mixer stage . . . albeit somewhat weaker than the principal 455/6 component.
::::::::
::::::::
::::::::You should be able to receive stronger stations from the Philco's coupled IF output , as being tuned into them.
::::::::
::::::::
::::::::Since I NOW know that you have another tubed AM BCB receiver as well as a small transistor radio . . .best that you initially try this procedure out on that combination of units to hone in your perceived effects . . .then move back to the Philco to see if it replicates with it . . . if so . . . our sets problem is on down the signal line flow from the mixer.
::::::::
::::::::
::::::::That also confirms that the micro-touchy tuning dial adjustement of the small transistor dial has "pre" found its 910 khz setting.
::::::::
::::::::
::::::::BTW . . .
::::::::
::::::::
::::::::Somewhere back in your threads branch offs there was mention of a 7H7 sitting in the RF slot . . . since this set is using 150 ma string filamental wiring . . .that starved tube would not come up to high enough emission temperature . . so be sure that either a 7C7 or 7B7 ends up in that RF tube slot. . . .which I think that you confirmed later on.
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::73's de Edd
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
::::::::
:::::::::OK I did it again. No stations but whistles everywhere a station would be on the transistor when I sweep the Philco which I think is the idea... Ed?
:::::::::
:::::::::
:::::::::
:::::::::
:::::::::
::::::::::i am going to do this again tonight. I did not understand or read the 910 part properly and also did not understand that the radio stations would come out of the Transistor radio not the philco,,
::::::::::
::::::::::Anyway I think the IF Trans must be shot as I did not do the turns ratio I was going by DC resistance. My bad.. So anyone have one that might work? WHere could I get a sub or can I use another as a substitute?
::::::::::
::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::Sir Bubba . . . . .
:::::::::::
:::::::::::
:::::::::::What wrong you . . . you no give up now !.
:::::::::::
:::::::::::
:::::::::::Now, just where do I get back on the train track again . . . there are Soooo many ravelings and branches, coming off from this thread.
:::::::::::
:::::::::::
:::::::::::OK then . . . I believe that your rework of that IF winding will work out OK in the end, as you probably TRIED to somewhat replicate its windings restructuring .
:::::::::::
:::::::::::
:::::::::::Probably the worse is your not being able to replicate that factory honeycomb winding pattern, and the end result of the coil now having more distributed capacitance in your rewind.
:::::::::::
:::::::::::
:::::::::::Not to worry . . .only meaning . . . that the re-trimming to 455/6 will require a bit less compression of its companion mica compression trimmer capacitor. .
:::::::::::
:::::::::::
:::::::::::I 'm goining to hope that there is some consideration that sets mixer and RF stages are operative, and as such, lets try this low tech exploration . . using no scooooppies nor instrumentation . . . 'jes some plain 'ole Yankee ingenuity.
:::::::::::
:::::::::::
:::::::::::It will need a pocket transistor AM radio . . . or even a small cased larger unit might suffice.
:::::::::::
:::::::::::
:::::::::::The idea is to fire up the Peeeeelco and take a 2-3 ft jumper ended clip lead and connect it to the plate of the mixer and and take the free end insulated wiring and make a capacitive loop turn around the body of the transistor radio.
:::::::::::
:::::::::::
:::::::::::We're just wanting close capacitive "gimmick" coupling between the two units . . . with quite a healthy 455/6v output from being direct connected to the plate of the mixer tube.
:::::::::::
:::::::::::
:::::::::::Next you fire up both units and guesstimate the transistor radios tuning, as being as close to . . 455 x2 = 910 on its dial scale as you can and off of any local station on that freq.
:::::::::::
:::::::::::
:::::::::::Volume goes up to max on the transistor and run the Philco tuning from one end to the other, hopefully if the RF mixer and local osc are OK on the Philco, ANY tuned in stations picked up on the Philco will be picked up as a 455 second harmonic of 910 on the transistor and being audible. Tune in your transistor to 910 more precisely, if anything is heard.
:::::::::::
:::::::::::
:::::::::::Now if you are bringing in stations on the transistor, by tuning them in on the Philco, the next step would be to move that plate connection to the Philco mixer stage on over to the plate of the IF amp, where . . . if its IF stage is functoning, strength should THEN be coming in like gangbusters . . . . as compared to just the former naked mixers output.
:::::::::::
:::::::::::
:::::::::::If you happen to have another tubed set that is probably also of 455 design, you just might initially try this procedure with it, to be able to hone your experience and expectations, and "pre" find 910 tuning on the transistor receiver..
:::::::::::
:::::::::::
:::::::::::Of course, if you have no transitor set, the other tubed sets loop antenna could receive the capacitively coupled in 455--->910 signal between the sets which I had initially mentioned..
:::::::::::
:::::::::::
:::::::::::Of course this is using the transistor set as a "signal tracer" , but could also work in the opposite manner as a 455/6 "signal generator" if you were to take the fiercely strong IF signal from the plate of the IF amp stage into the clip leaded test lead .
:::::::::::Then you initially couple it thru an isolative 50-100pf . .etc into the detector diode of the Philco
:::::::::::and then work forward in the Phico to its plate connection and then the 1st grid of the sets IF amp stage to see if the received stations reception increases on up to the initial point of derivgation from the plate of the Philco mixer toobie.
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::Now . . . lets's do-it-to-it . . . stations Ahoy ! . . . aka . . . Can you hear me . . . can you hear me now ?
:::::::::::
:::::::::::
:::::::::::73's de Edd
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
:::::::::::
::::::::::::Idealy, however, it would be a good idea to go on eBay and purchase a working signal generator. This would make matters much easier. Even if the signal generator isn't too accurate, it can be calibrated on a working radio and then be used to troubleshoot a non-working radio.
::::::::::::
::::::::::::T.
::::::::::::
:::::::::::
:::::::::::
::::::::::
::::::::::
:::::::::
:::::::::
::::::::
::::::::
:::::::
:::::::
::::::
::::::
:::::
:::::
::::
::::
:::
:::
::
::
:
:
http://cgi.ebay.com/aa55-Heathkit-RF-Signal-Generator-Model-IG-102-works-/370514939284?_trksid=p4340.m263&_trkparms=algo%3DSIC%26its%3DI%252BC%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%26otn%3D10%26pmod%3D250808677588%26ps%3D63%26clkid%3D325888302878010038
:::
:::I am not sure what next to try though to get a sation out of this thing. I guess I might have to find someone with a scope and AC Generator.
:::
:::
::::
::::
::::
::::::The jumpering Pin 6 thing with cap in the middle together didn't work I don't have a germanium diode. I have silicon though.
::::::
::::::I need to get some proper test equipment.
::::::
::::::
::::::
:::::::I am going ot try it what size of cap should I use?
:::::::
:::::::THX
:::::::
:::::::
:::::::
::::::::Since you don’t have any test equipment, a low tech crude way is one way to go. A capacitor from pin 6 of the 7C7 to pin 6 of the 7A8 does bypass the RF amp. The tuner will still work for a strong station. (Not that well) Capacitor from pin 2 of the 7A8 to pin 6 of the 7B7 bypass the 1st IF. And from pin 2 of the 7B7 to pin 6 of the 7C6 (already been there) this can be inconclusive. But it’s something to try. You can make your own signal tracer. A pair of powered computer speakers is an audio amplifier. You would use a germanium diode and around a .01 capacitor in series with the input end of one speaker channel. ( Or both channels tied together ). The anode side of the diode would be the test end to the radio components. The common ground of both channels to chassis ground of the radio. Basically a RF signal tracer like this is like a crystal radio. The diode is the detector, and any RF is amplified though the audio amp to its speakers.
::::::::
:::::::
:::::::
::::::
::::::
:::::Hi Bubba,
::::: Warren has been giving great advice, however, I would not have removed the gimmik wire. Your test does not exonerate the IF can.
::::: Moreover, the way you are struggling here indicates there are two problems. One of them could be that IF can.
::::: How does that other IF can look?
::::: Just think how great it will sound when you get it working!
:::::
:::::Best Regards,
:::::
:::::Bill
:::::
:::::Best R
:::::
::::
::::
:::
:::
::Hi Bubba,
:: It seems like we have centered down on the problem(s) being in the IF, although the RF input hasn't been verified. Your oscilator seems to be OK.
:: Without a signal generator, your options are limited.
:: You may want to consider trying a capacitor around the first IF can. You may have a coupling problem there, too.
::
:: Even if you get sound out of the radio, you will need a signal generator to align it properly. Era tuning with a radio station may get you close, but performance will not likely be great.
::
:: Let's see how that second capacitor does.
::
::All the Best,
::
::Bill
::
:
:Can I use a 1n4005 Diode for the signal tracer? I do not have a germanium diode.
:
:Bubba
:
:
Hello Bubba,
The 1N4005 should be used in rectifier circuits with higher watt resistors such as in the replacement of a 117Z3 tube where you make it a solid state circuit and have much less heat with the tube removed.
Use a germanian diode for the detector, it has different charistics from rectifier diodes.
A good one is part number 1N34A, I bought some from Newark Electronics or you may find some lodally.
Mitch