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Chasing Ghosts & Getting Murphy out of the room
3/4/2006 4:25:54 PMPeter Balazsy
(Murphy's law)
The other night ...ALL NIGHT... I was working on the nice old Gilfillan that seemed to work so nicely after I had recapped it last week.
http://www.nostalgiaair.org/PagesByModel/612/M0008612.pdf ( The bottom drawing)
Although there might still be the original nagging problem where the entire set would just go dead once in a while with the filaments on.. or the B+ which seemed to change from time to time... 200v or sometimes 150v.
But after recapping I thought it was alright.
This radio has a funny power supply arrangement where it has one filter cap referenced to the CT and the other to the chassis... so I wasn't sure where to take my B+ measurements from. ( though Thomas feels it should be the chassis)
Anyway... I decided to clean all the crud off the metal and scrub away all the gunky solder residue and wax etc etc. So I removed all parts like tuning codenser and speaker etc. Then I cleaned it in the sink with household cleaning products using a minimum of water and dried it with a hair drier and reassembled it.
The tuning condenser was also washed and came out like new.
After re-assembly I had the "dead" problem again. Audio section worked but no rf signal.. so I started chasing that down and discoverd low B+ again. There had been a smell of heat too ... so I felt the transformer which was too hot. Ok sure enough the HV 350-0-350 winding was unbalanced and getting worse as it got hotter.
So..I ordered up a new transformer.
While waiting for it to arrive I took the time to scrub the oxidation off the metal chassis with a scotch brite pad, wire brushes and light sandpaper. Looks terrific!
I got the new transformer and was replacing it the other night when everything, step after step, seemed to be going wrong. (I just knew Murphy was in the room but I didn't know where)
I spent most of the night chasing down weird problem after problem and... after I finally found the causes of these mysterious happenings all I could do was laugh and kick myself.
The symptoms varied from things like testing the new transformer by using clip leads to connect it temporarily... and finding voltages that would appear then disappear. Rearranging circuit elements like swapping rectifier tubes with diodes using clip leads to make comparison voltage readings and finding nothing was working consistantly. Then getting it back together and having problems getting a signal as I tried to clip a longwire antenna on.. sometimes it worked and then it didn't
What caused all that???...

====>> BAD clip leads!!!

I bought some new clip-leads recently and mixed them in with the others. But upon examination last night...I found that the aligator clips were not soldered to the wires under the rubber clip covers!!! Some were worse than others just partially crimped on the insulation and the wire strands laying there sort of touching!!!
Now these are things you just never question !!!
So how often lately have these things been making my readings go nuts now I wonder???
I'll resolder and test EVERY lead now before I put them back on my beach, you can bet.

Next:
... When trying to alighn the IFs and finding all kinds of weak then strong signals as I connected my signal generator... I'd get a nice strong signal... then it would dissapear... same thing with tryng to calibrate the Rf tracking..
All night nothing worked the same WAY twice during alignment.

What do you think was the problem there?

====>> LOOSE OUTPUT CABLE CONNECTION on the Signal Generator!!!!!!!!!

The coax cable that screws on the front of the Heathkit generator had slowly started to become un-screwed!!! The connector was barely screwed on!! I guess that everytime I coil-up that wire a and tuck it under the handel when I'm finished using it... I guess I must turn it somehow such that it unscrews itself!

Now that one really hurt. Especially because you can't even see that it's unscrewed.. it looked fine. Hah!

Then I get everything...almost working... but the signal is weak or drifts and distorted. I can get only the strongest station in my area nice and clean but the others hardly come in or are distorted mostly. If I put my finger on the 6a7 grid cap I get strong signals and almost nothing connected to the longwire makes much difference.
What was the problem here?

====>> broken hair-thin wire at the solder connection lug of the "broadcast antenna bandpass coil".
WHY??? because as I was sanding the surface of the chassis I bumped the coil a few times but it looked fine to my eye. Even under close scrutiny with an eye-loupe .. it looked fine... but when I gently probed it with a stylus it was not connected.
My fault. The coil mounts on top of the chassis by a single screw on one area of the coil cardboard tube. Kind of crooked and like a loose tooth. But I didn't think that I was damaging it as I cleaned around it.

But usually when something goes wrong.. it's the last thing you were working on.
And that's the last thing I did before I put the transformer back on.!!

So a simple 1 hour job eneded up taking the entire night and part of the next day... all because of things you just almost never think of... that are usually deliverd neatly in your lap by by our old friend Murphy.


3/6/2006 5:12:21 AMGary W. Prutchick
Peter,

This Murphy guy gets around or he has a twin! I too have spent many a night chassing similar problems. The poorly soldered clip leads for example. When in the heat of a restoration, sometimes the blinders prevent us from stepping back and logically assessing the situation. For me the blinders come in the form of questions and statements like; What did I do now? I must have made an error?. I must have installed the wrong value of component. Maybe these new capacitors are bad? I wonder if there is an error on this schematic? Maybe I should replace the tube(s) agian, usually trying every spare tube in my stock. I know, maybe another allignment attempt will fix it. This is a very strange problem, it doesn't make sense, it defies the laws of physics and I am going to figure it out, even if it takes all night, and it usually does.

I admire your attitude and thank you for sharing your experience. It helps me, and most likely everyone else, realize that %&*$@#*$&% happens.

Gary W. Prutchick

:(Murphy's law)
:The other night ...ALL NIGHT... I was working on the nice old Gilfillan that seemed to work so nicely after I had recapped it last week.
:http://www.nostalgiaair.org/PagesByModel/612/M0008612.pdf ( The bottom drawing)
:Although there might still be the original nagging problem where the entire set would just go dead once in a while with the filaments on.. or the B+ which seemed to change from time to time... 200v or sometimes 150v.
:But after recapping I thought it was alright.
:This radio has a funny power supply arrangement where it has one filter cap referenced to the CT and the other to the chassis... so I wasn't sure where to take my B+ measurements from. ( though Thomas feels it should be the chassis)
:Anyway... I decided to clean all the crud off the metal and scrub away all the gunky solder residue and wax etc etc. So I removed all parts like tuning codenser and speaker etc. Then I cleaned it in the sink with household cleaning products using a minimum of water and dried it with a hair drier and reassembled it.
:The tuning condenser was also washed and came out like new.
:After re-assembly I had the "dead" problem again. Audio section worked but no rf signal.. so I started chasing that down and discoverd low B+ again. There had been a smell of heat too ... so I felt the transformer which was too hot. Ok sure enough the HV 350-0-350 winding was unbalanced and getting worse as it got hotter.
:So..I ordered up a new transformer.
: While waiting for it to arrive I took the time to scrub the oxidation off the metal chassis with a scotch brite pad, wire brushes and light sandpaper. Looks terrific!
:I got the new transformer and was replacing it the other night when everything, step after step, seemed to be going wrong. (I just knew Murphy was in the room but I didn't know where)
:I spent most of the night chasing down weird problem after problem and... after I finally found the causes of these mysterious happenings all I could do was laugh and kick myself.
:The symptoms varied from things like testing the new transformer by using clip leads to connect it temporarily... and finding voltages that would appear then disappear. Rearranging circuit elements like swapping rectifier tubes with diodes using clip leads to make comparison voltage readings and finding nothing was working consistantly. Then getting it back together and having problems getting a signal as I tried to clip a longwire antenna on.. sometimes it worked and then it didn't
:What caused all that???...
:
: ====>> BAD clip leads!!!
:
:I bought some new clip-leads recently and mixed them in with the others. But upon examination last night...I found that the aligator clips were not soldered to the wires under the rubber clip covers!!! Some were worse than others just partially crimped on the insulation and the wire strands laying there sort of touching!!!
:Now these are things you just never question !!!
:So how often lately have these things been making my readings go nuts now I wonder???
:I'll resolder and test EVERY lead now before I put them back on my beach, you can bet.
:
:Next:
:... When trying to alighn the IFs and finding all kinds of weak then strong signals as I connected my signal generator... I'd get a nice strong signal... then it would dissapear... same thing with tryng to calibrate the Rf tracking..
:All night nothing worked the same WAY twice during alignment.
:
:What do you think was the problem there?
:
:====>> LOOSE OUTPUT CABLE CONNECTION on the Signal Generator!!!!!!!!!
:
:The coax cable that screws on the front of the Heathkit generator had slowly started to become un-screwed!!! The connector was barely screwed on!! I guess that everytime I coil-up that wire a and tuck it under the handel when I'm finished using it... I guess I must turn it somehow such that it unscrews itself!
:
:Now that one really hurt. Especially because you can't even see that it's unscrewed.. it looked fine. Hah!
:
:Then I get everything...almost working... but the signal is weak or drifts and distorted. I can get only the strongest station in my area nice and clean but the others hardly come in or are distorted mostly. If I put my finger on the 6a7 grid cap I get strong signals and almost nothing connected to the longwire makes much difference.
:What was the problem here?
:
:====>> broken hair-thin wire at the solder connection lug of the "broadcast antenna bandpass coil".
:WHY??? because as I was sanding the surface of the chassis I bumped the coil a few times but it looked fine to my eye. Even under close scrutiny with an eye-loupe .. it looked fine... but when I gently probed it with a stylus it was not connected.
:My fault. The coil mounts on top of the chassis by a single screw on one area of the coil cardboard tube. Kind of crooked and like a loose tooth. But I didn't think that I was damaging it as I cleaned around it.
:
:But usually when something goes wrong.. it's the last thing you were working on.
:And that's the last thing I did before I put the transformer back on.!!
:
:So a simple 1 hour job eneded up taking the entire night and part of the next day... all because of things you just almost never think of... that are usually deliverd neatly in your lap by by our old friend Murphy.
:
:
:

3/6/2006 12:34:06 PMDennis Wess
Very enlightening........as a matter of fact I strongly suspect that Murphy has been cloned many many times.

Dennis

:Peter,
:
:This Murphy guy gets around or he has a twin! I too have spent many a night chassing similar problems. The poorly soldered clip leads for example. When in the heat of a restoration, sometimes the blinders prevent us from stepping back and logically assessing the situation. For me the blinders come in the form of questions and statements like; What did I do now? I must have made an error?. I must have installed the wrong value of component. Maybe these new capacitors are bad? I wonder if there is an error on this schematic? Maybe I should replace the tube(s) agian, usually trying every spare tube in my stock. I know, maybe another allignment attempt will fix it. This is a very strange problem, it doesn't make sense, it defies the laws of physics and I am going to figure it out, even if it takes all night, and it usually does.
:
:I admire your attitude and thank you for sharing your experience. It helps me, and most likely everyone else, realize that %&*$@#*$&% happens.
:
:Gary W. Prutchick
:
::(Murphy's law)
::The other night ...ALL NIGHT... I was working on the nice old Gilfillan that seemed to work so nicely after I had recapped it last week.
::http://www.nostalgiaair.org/PagesByModel/612/M0008612.pdf ( The bottom drawing)
::Although there might still be the original nagging problem where the entire set would just go dead once in a while with the filaments on.. or the B+ which seemed to change from time to time... 200v or sometimes 150v.
::But after recapping I thought it was alright.
::This radio has a funny power supply arrangement where it has one filter cap referenced to the CT and the other to the chassis... so I wasn't sure where to take my B+ measurements from. ( though Thomas feels it should be the chassis)
::Anyway... I decided to clean all the crud off the metal and scrub away all the gunky solder residue and wax etc etc. So I removed all parts like tuning codenser and speaker etc. Then I cleaned it in the sink with household cleaning products using a minimum of water and dried it with a hair drier and reassembled it.
::The tuning condenser was also washed and came out like new.
::After re-assembly I had the "dead" problem again. Audio section worked but no rf signal.. so I started chasing that down and discoverd low B+ again. There had been a smell of heat too ... so I felt the transformer which was too hot. Ok sure enough the HV 350-0-350 winding was unbalanced and getting worse as it got hotter.
::So..I ordered up a new transformer.
:: While waiting for it to arrive I took the time to scrub the oxidation off the metal chassis with a scotch brite pad, wire brushes and light sandpaper. Looks terrific!
::I got the new transformer and was replacing it the other night when everything, step after step, seemed to be going wrong. (I just knew Murphy was in the room but I didn't know where)
::I spent most of the night chasing down weird problem after problem and... after I finally found the causes of these mysterious happenings all I could do was laugh and kick myself.
::The symptoms varied from things like testing the new transformer by using clip leads to connect it temporarily... and finding voltages that would appear then disappear. Rearranging circuit elements like swapping rectifier tubes with diodes using clip leads to make comparison voltage readings and finding nothing was working consistantly. Then getting it back together and having problems getting a signal as I tried to clip a longwire antenna on.. sometimes it worked and then it didn't
::What caused all that???...
::
:: ====>> BAD clip leads!!!
::
::I bought some new clip-leads recently and mixed them in with the others. But upon examination last night...I found that the aligator clips were not soldered to the wires under the rubber clip covers!!! Some were worse than others just partially crimped on the insulation and the wire strands laying there sort of touching!!!
::Now these are things you just never question !!!
::So how often lately have these things been making my readings go nuts now I wonder???
::I'll resolder and test EVERY lead now before I put them back on my beach, you can bet.
::
::Next:
::... When trying to alighn the IFs and finding all kinds of weak then strong signals as I connected my signal generator... I'd get a nice strong signal... then it would dissapear... same thing with tryng to calibrate the Rf tracking..
::All night nothing worked the same WAY twice during alignment.
::
::What do you think was the problem there?
::
::====>> LOOSE OUTPUT CABLE CONNECTION on the Signal Generator!!!!!!!!!
::
::The coax cable that screws on the front of the Heathkit generator had slowly started to become un-screwed!!! The connector was barely screwed on!! I guess that everytime I coil-up that wire a and tuck it under the handel when I'm finished using it... I guess I must turn it somehow such that it unscrews itself!
::
::Now that one really hurt. Especially because you can't even see that it's unscrewed.. it looked fine. Hah!
::
::Then I get everything...almost working... but the signal is weak or drifts and distorted. I can get only the strongest station in my area nice and clean but the others hardly come in or are distorted mostly. If I put my finger on the 6a7 grid cap I get strong signals and almost nothing connected to the longwire makes much difference.
::What was the problem here?
::
::====>> broken hair-thin wire at the solder connection lug of the "broadcast antenna bandpass coil".
::WHY??? because as I was sanding the surface of the chassis I bumped the coil a few times but it looked fine to my eye. Even under close scrutiny with an eye-loupe .. it looked fine... but when I gently probed it with a stylus it was not connected.
::My fault. The coil mounts on top of the chassis by a single screw on one area of the coil cardboard tube. Kind of crooked and like a loose tooth. But I didn't think that I was damaging it as I cleaned around it.
::
::But usually when something goes wrong.. it's the last thing you were working on.
::And that's the last thing I did before I put the transformer back on.!!
::
::So a simple 1 hour job eneded up taking the entire night and part of the next day... all because of things you just almost never think of... that are usually deliverd neatly in your lap by by our old friend Murphy.
::
::
::

3/6/2006 10:01:17 PMMAG
:Very enlightening........as a matter of fact I strongly suspect that Murphy has been cloned many many times.
:
:Dennis
:
:
:
::Peter,
::
::This Murphy guy gets around or he has a twin! I too have spent many a night chassing similar problems. The poorly soldered clip leads for example. When in the heat of a restoration, sometimes the blinders prevent us from stepping back and logically assessing the situation. For me the blinders come in the form of questions and statements like; What did I do now? I must have made an error?. I must have installed the wrong value of component. Maybe these new capacitors are bad? I wonder if there is an error on this schematic? Maybe I should replace the tube(s) agian, usually trying every spare tube in my stock. I know, maybe another allignment attempt will fix it. This is a very strange problem, it doesn't make sense, it defies the laws of physics and I am going to figure it out, even if it takes all night, and it usually does.
::
::I admire your attitude and thank you for sharing your experience. It helps me, and most likely everyone else, realize that %&*$@#*$&% happens.
::
::Gary W. Prutchick
::
:::(Murphy's law)
:::The other night ...ALL NIGHT... I was working on the nice old Gilfillan that seemed to work so nicely after I had recapped it last week.
:::http://www.nostalgiaair.org/PagesByModel/612/M0008612.pdf ( The bottom drawing)
:::Although there might still be the original nagging problem where the entire set would just go dead once in a while with the filaments on.. or the B+ which seemed to change from time to time... 200v or sometimes 150v.
:::But after recapping I thought it was alright.
:::This radio has a funny power supply arrangement where it has one filter cap referenced to the CT and the other to the chassis... so I wasn't sure where to take my B+ measurements from. ( though Thomas feels it should be the chassis)
:::Anyway... I decided to clean all the crud off the metal and scrub away all the gunky solder residue and wax etc etc. So I removed all parts like tuning codenser and speaker etc. Then I cleaned it in the sink with household cleaning products using a minimum of water and dried it with a hair drier and reassembled it.
:::The tuning condenser was also washed and came out like new.
:::After re-assembly I had the "dead" problem again. Audio section worked but no rf signal.. so I started chasing that down and discoverd low B+ again. There had been a smell of heat too ... so I felt the transformer which was too hot. Ok sure enough the HV 350-0-350 winding was unbalanced and getting worse as it got hotter.
:::So..I ordered up a new transformer.
::: While waiting for it to arrive I took the time to scrub the oxidation off the metal chassis with a scotch brite pad, wire brushes and light sandpaper. Looks terrific!
:::I got the new transformer and was replacing it the other night when everything, step after step, seemed to be going wrong. (I just knew Murphy was in the room but I didn't know where)
:::I spent most of the night chasing down weird problem after problem and... after I finally found the causes of these mysterious happenings all I could do was laugh and kick myself.
:::The symptoms varied from things like testing the new transformer by using clip leads to connect it temporarily... and finding voltages that would appear then disappear. Rearranging circuit elements like swapping rectifier tubes with diodes using clip leads to make comparison voltage readings and finding nothing was working consistantly. Then getting it back together and having problems getting a signal as I tried to clip a longwire antenna on.. sometimes it worked and then it didn't
:::What caused all that???...
:::
::: ====>> BAD clip leads!!!
:::
:::I bought some new clip-leads recently and mixed them in with the others. But upon examination last night...I found that the aligator clips were not soldered to the wires under the rubber clip covers!!! Some were worse than others just partially crimped on the insulation and the wire strands laying there sort of touching!!!
:::Now these are things you just never question !!!
:::So how often lately have these things been making my readings go nuts now I wonder???
:::I'll resolder and test EVERY lead now before I put them back on my beach, you can bet.
:::
:::Next:
:::... When trying to alighn the IFs and finding all kinds of weak then strong signals as I connected my signal generator... I'd get a nice strong signal... then it would dissapear... same thing with tryng to calibrate the Rf tracking..
:::All night nothing worked the same WAY twice during alignment.
:::
:::What do you think was the problem there?
:::
:::====>> LOOSE OUTPUT CABLE CONNECTION on the Signal Generator!!!!!!!!!
:::
:::The coax cable that screws on the front of the Heathkit generator had slowly started to become un-screwed!!! The connector was barely screwed on!! I guess that everytime I coil-up that wire a and tuck it under the handel when I'm finished using it... I guess I must turn it somehow such that it unscrews itself!
:::
:::Now that one really hurt. Especially because you can't even see that it's unscrewed.. it looked fine. Hah!
:::
:::Then I get everything...almost working... but the signal is weak or drifts and distorted. I can get only the strongest station in my area nice and clean but the others hardly come in or are distorted mostly. If I put my finger on the 6a7 grid cap I get strong signals and almost nothing connected to the longwire makes much difference.
:::What was the problem here?
:::
:::====>> broken hair-thin wire at the solder connection lug of the "broadcast antenna bandpass coil".
:::WHY??? because as I was sanding the surface of the chassis I bumped the coil a few times but it looked fine to my eye. Even under close scrutiny with an eye-loupe .. it looked fine... but when I gently probed it with a stylus it was not connected.
:::My fault. The coil mounts on top of the chassis by a single screw on one area of the coil cardboard tube. Kind of crooked and like a loose tooth. But I didn't think that I was damaging it as I cleaned around it.
:::
:::But usually when something goes wrong.. it's the last thing you were working on.
:::And that's the last thing I did before I put the transformer back on.!!
:::
:::So a simple 1 hour job eneded up taking the entire night and part of the next day... all because of things you just almost never think of... that are usually deliverd neatly in your lap by by our old friend Murphy.
:::
:::
Murphy and clip leads are partners in the frustration game!! I finally got tired of fooling with the skimpy wires that aren't firmly attached to the tin-foil alligator clips about 20 years ago. At one of our local ham swap meets, I found a guy selling bulk rubber covered test lead wire in different colors; green, yellow, white, and of course , red and black. I bought enough of each color to make up four clip leads each. Another guy at the same meet had genuine good ole Made in USA Mueller alligator clips and colored boots for them. That was the end of my clip lead problems. In 20 or more years, only one has failed me, and it just plain wore out!
Murphy is still out there, but he has to find other partners to devil me with now.
Meade
:::
3/6/2006 4:26:16 PMTonyC
A few weeks ago I was bored and decided to finish recapping my old signal generator. I had recapped it long ago and I have been using it without any problems but there was one cap down inside the big copper cage that I didn't do because it was buried. The drum with all the coils on it is inside the cage and you have to remove it (the drum) to get to the cap. No big deal. take off the knob and the bracket that supports the back of the drum and lift it out.

The cap was still a pain to get to but eventually I succeeded and I put it all back together, including the 12 screws holding the cover on the copper cage.

Turn it on and Band B doesn't work anymore. Disassemble everything again. It looks OK. But wait, what is that tiny tiny nick on the band B coil? The coil is open. Under a magnifying glass you could see that I had bumped it against the edge of the cage and broken the fine Litz wire. This was the 100Khz band so the coil had a bazillion turns on it. Fortunately it was only about 10 turns in where it was broken. I can't duplicate the style of the windings by hand so now I have this coil in there with a bunch of scramble wound turns on top of it. Ugly. But it works again.

That cap probably would have lasted another 50 years but, no, I HAD to replace the last one.

Oh, and I have done my turn with the clip leads too. At least one day spent looking for the intermittent. When I figured out it was the clip lead, I threw it in the trash. It felt good to get even.

:(Murphy's law)
:The other night ...ALL NIGHT... I was working on the nice old Gilfillan that seemed to work so nicely after I had recapped it last week.
:http://www.nostalgiaair.org/PagesByModel/612/M0008612.pdf ( The bottom drawing)
:Although there might still be the original nagging problem where the entire set would just go dead once in a while with the filaments on.. or the B+ which seemed to change from time to time... 200v or sometimes 150v.
:But after recapping I thought it was alright.
:This radio has a funny power supply arrangement where it has one filter cap referenced to the CT and the other to the chassis... so I wasn't sure where to take my B+ measurements from. ( though Thomas feels it should be the chassis)
:Anyway... I decided to clean all the crud off the metal and scrub away all the gunky solder residue and wax etc etc. So I removed all parts like tuning codenser and speaker etc. Then I cleaned it in the sink with household cleaning products using a minimum of water and dried it with a hair drier and reassembled it.
:The tuning condenser was also washed and came out like new.
:After re-assembly I had the "dead" problem again. Audio section worked but no rf signal.. so I started chasing that down and discoverd low B+ again. There had been a smell of heat too ... so I felt the transformer which was too hot. Ok sure enough the HV 350-0-350 winding was unbalanced and getting worse as it got hotter.
:So..I ordered up a new transformer.
: While waiting for it to arrive I took the time to scrub the oxidation off the metal chassis with a scotch brite pad, wire brushes and light sandpaper. Looks terrific!
:I got the new transformer and was replacing it the other night when everything, step after step, seemed to be going wrong. (I just knew Murphy was in the room but I didn't know where)
:I spent most of the night chasing down weird problem after problem and... after I finally found the causes of these mysterious happenings all I could do was laugh and kick myself.
:The symptoms varied from things like testing the new transformer by using clip leads to connect it temporarily... and finding voltages that would appear then disappear. Rearranging circuit elements like swapping rectifier tubes with diodes using clip leads to make comparison voltage readings and finding nothing was working consistantly. Then getting it back together and having problems getting a signal as I tried to clip a longwire antenna on.. sometimes it worked and then it didn't
:What caused all that???...
:
: ====>> BAD clip leads!!!
:
:I bought some new clip-leads recently and mixed them in with the others. But upon examination last night...I found that the aligator clips were not soldered to the wires under the rubber clip covers!!! Some were worse than others just partially crimped on the insulation and the wire strands laying there sort of touching!!!
:Now these are things you just never question !!!
:So how often lately have these things been making my readings go nuts now I wonder???
:I'll resolder and test EVERY lead now before I put them back on my beach, you can bet.
:
:Next:
:... When trying to alighn the IFs and finding all kinds of weak then strong signals as I connected my signal generator... I'd get a nice strong signal... then it would dissapear... same thing with tryng to calibrate the Rf tracking..
:All night nothing worked the same WAY twice during alignment.
:
:What do you think was the problem there?
:
:====>> LOOSE OUTPUT CABLE CONNECTION on the Signal Generator!!!!!!!!!
:
:The coax cable that screws on the front of the Heathkit generator had slowly started to become un-screwed!!! The connector was barely screwed on!! I guess that everytime I coil-up that wire a and tuck it under the handel when I'm finished using it... I guess I must turn it somehow such that it unscrews itself!
:
:Now that one really hurt. Especially because you can't even see that it's unscrewed.. it looked fine. Hah!
:
:Then I get everything...almost working... but the signal is weak or drifts and distorted. I can get only the strongest station in my area nice and clean but the others hardly come in or are distorted mostly. If I put my finger on the 6a7 grid cap I get strong signals and almost nothing connected to the longwire makes much difference.
:What was the problem here?
:
:====>> broken hair-thin wire at the solder connection lug of the "broadcast antenna bandpass coil".
:WHY??? because as I was sanding the surface of the chassis I bumped the coil a few times but it looked fine to my eye. Even under close scrutiny with an eye-loupe .. it looked fine... but when I gently probed it with a stylus it was not connected.
:My fault. The coil mounts on top of the chassis by a single screw on one area of the coil cardboard tube. Kind of crooked and like a loose tooth. But I didn't think that I was damaging it as I cleaned around it.
:
:But usually when something goes wrong.. it's the last thing you were working on.
:And that's the last thing I did before I put the transformer back on.!!
:
:So a simple 1 hour job eneded up taking the entire night and part of the next day... all because of things you just almost never think of... that are usually deliverd neatly in your lap by by our old friend Murphy.
:
:
:

3/6/2006 10:33:16 PMDavid
You guys got me thinking, I just recapped a philco 48-1262 and upon finishing everything it worked fine, but only got a loud whaling sounds when ever I tuned in a station. I was testing this on the bench using aligator clips to attach the antenna--I just checked and found that Murphy was in my shop, he had broke one of the leads on my aligator clips. I soldered it back in place now I can pick up stations crystal clear. WOW...LOL..how could I have missed this one????
David
3/6/2006 11:29:26 PMPeter Balazsy
Boy you guys thanks for your stories!
...it sure is nice to hear all your sympathetic and similar maladies...
Also ... so nice to know I'm not out here alone slaying these dragons. lol
3/6/2006 11:47:55 PMMarv Nuce
All,
Sounds like my woodworking instructor in high school!! Measure twice, cut once.

marv

:(Murphy's law)
:The other night ...ALL NIGHT... I was working on the nice old Gilfillan that seemed to work so nicely after I had recapped it last week.
:http://www.nostalgiaair.org/PagesByModel/612/M0008612.pdf ( The bottom drawing)
:Although there might still be the original nagging problem where the entire set would just go dead once in a while with the filaments on.. or the B+ which seemed to change from time to time... 200v or sometimes 150v.
:But after recapping I thought it was alright.
:This radio has a funny power supply arrangement where it has one filter cap referenced to the CT and the other to the chassis... so I wasn't sure where to take my B+ measurements from. ( though Thomas feels it should be the chassis)
:Anyway... I decided to clean all the crud off the metal and scrub away all the gunky solder residue and wax etc etc. So I removed all parts like tuning codenser and speaker etc. Then I cleaned it in the sink with household cleaning products using a minimum of water and dried it with a hair drier and reassembled it.
:The tuning condenser was also washed and came out like new.
:After re-assembly I had the "dead" problem again. Audio section worked but no rf signal.. so I started chasing that down and discoverd low B+ again. There had been a smell of heat too ... so I felt the transformer which was too hot. Ok sure enough the HV 350-0-350 winding was unbalanced and getting worse as it got hotter.
:So..I ordered up a new transformer.
: While waiting for it to arrive I took the time to scrub the oxidation off the metal chassis with a scotch brite pad, wire brushes and light sandpaper. Looks terrific!
:I got the new transformer and was replacing it the other night when everything, step after step, seemed to be going wrong. (I just knew Murphy was in the room but I didn't know where)
:I spent most of the night chasing down weird problem after problem and... after I finally found the causes of these mysterious happenings all I could do was laugh and kick myself.
:The symptoms varied from things like testing the new transformer by using clip leads to connect it temporarily... and finding voltages that would appear then disappear. Rearranging circuit elements like swapping rectifier tubes with diodes using clip leads to make comparison voltage readings and finding nothing was working consistantly. Then getting it back together and having problems getting a signal as I tried to clip a longwire antenna on.. sometimes it worked and then it didn't
:What caused all that???...
:
: ====>> BAD clip leads!!!
:
:I bought some new clip-leads recently and mixed them in with the others. But upon examination last night...I found that the aligator clips were not soldered to the wires under the rubber clip covers!!! Some were worse than others just partially crimped on the insulation and the wire strands laying there sort of touching!!!
:Now these are things you just never question !!!
:So how often lately have these things been making my readings go nuts now I wonder???
:I'll resolder and test EVERY lead now before I put them back on my beach, you can bet.
:
:Next:
:... When trying to alighn the IFs and finding all kinds of weak then strong signals as I connected my signal generator... I'd get a nice strong signal... then it would dissapear... same thing with tryng to calibrate the Rf tracking..
:All night nothing worked the same WAY twice during alignment.
:
:What do you think was the problem there?
:
:====>> LOOSE OUTPUT CABLE CONNECTION on the Signal Generator!!!!!!!!!
:
:The coax cable that screws on the front of the Heathkit generator had slowly started to become un-screwed!!! The connector was barely screwed on!! I guess that everytime I coil-up that wire a and tuck it under the handel when I'm finished using it... I guess I must turn it somehow such that it unscrews itself!
:
:Now that one really hurt. Especially because you can't even see that it's unscrewed.. it looked fine. Hah!
:
:Then I get everything...almost working... but the signal is weak or drifts and distorted. I can get only the strongest station in my area nice and clean but the others hardly come in or are distorted mostly. If I put my finger on the 6a7 grid cap I get strong signals and almost nothing connected to the longwire makes much difference.
:What was the problem here?
:
:====>> broken hair-thin wire at the solder connection lug of the "broadcast antenna bandpass coil".
:WHY??? because as I was sanding the surface of the chassis I bumped the coil a few times but it looked fine to my eye. Even under close scrutiny with an eye-loupe .. it looked fine... but when I gently probed it with a stylus it was not connected.
:My fault. The coil mounts on top of the chassis by a single screw on one area of the coil cardboard tube. Kind of crooked and like a loose tooth. But I didn't think that I was damaging it as I cleaned around it.
:
:But usually when something goes wrong.. it's the last thing you were working on.
:And that's the last thing I did before I put the transformer back on.!!
:
:So a simple 1 hour job eneded up taking the entire night and part of the next day... all because of things you just almost never think of... that are usually deliverd neatly in your lap by by our old friend Murphy.
:
:
:

3/7/2006 12:28:31 AMPeter Balazsy
I'm taking a break from burned fingers..soldering all my junky 39 cent clip leads to catch up here with the forum & you guys... and those crappy leads have only about 5 strands of wire in there too... and even the minimal heat from my 25 watt iron melted the pseudo-rubber insulation.. that stuff seems to be made of extruded marshmallow with food coloring...!! never saw anything worse.. lol
and... so...Y'know I was going to complain some more about it like...you can't even buy quality stuff if you want. Like where do you get those top quality jummpers from.. who sells 'em anymore?
Even if you find a large supply house and call them to find out... ten you can't even ever find a real person to talk to on the phone about your choices... you can't get people for anything anymore... ever!!
And if you do get some "customer service" types at your bank or credit card company or ANY place... and you need to tell them that thier lousy phone menu choice thing is screwed up and it doesn't have a choice for what you need..EVER!... all they say is.. "yeah, I agree it's the computer, we all feel like you do"... Well DUH....
HECK... then DO something about it! .. don't just give me sympathy.
I don't need sympathy... If all I wanted was sympathy... I'd look it up in the dictionary .. it's between "Shafted" & "Syphilis"

Almost everything today is made in China by blind cheapos... everything is only made to " sort-of look good" but really isn't... Like almost EVERYTHING in the $1 store....
I mean here and there a pack of foam paint brushes that you toss after 10 minuets is fine... or a greeting card..
But nothing else hardley... but in the $1 store you expect crap.
But when I want to buy the best in bench test stuff like clip leads, soldering irons etc... every website supply place seems to only carry that cheap chineese junk.
Isn't there anyone in China that makes anything of quality ever?
Well... so I searched a lot and found that this site at least addresses the specific problem of unsoldered leads and claims that theirs are made properly and well soldered.
Here it is but it still looks suspiciously junky:
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=360-150
3/7/2006 12:57:51 AMDavid
YEAH--don't get me started. RADIO SHACK...this has turned into the most usless store ever...what they really need to do is take the word Radio out of there name and replace it with MADE IN TIAWAN. I went in there the other day for a capacitor and the young man said that those thiningies are over there, so I walk over there now pissed and found drawers filled with mainly rca jacks and computer cables and to find about a dozen usless sizes and low voltage capacitors--I left and swore to never return.
David
3/7/2006 8:40:18 AMDavid
I have given up on Radio Shack some twenty years ago due to the lack of knowledge by the sales staff, and forget about ordering from them as the staff is not sure that they can order parts that are not on display. The only good thing I purchased from them was a small 13 inch color TV back in 1982-83 that is still working (the remote control gave up 6 months ago), everything else has been junk, such as a wireless FM mic that picked up CB radios (due to poor filtering in both the transmitter and reciver.

:YEAH--don't get me started. RADIO SHACK...this has turned into the most usless store ever...what they really need to do is take the word Radio out of there name and replace it with MADE IN TIAWAN. I went in there the other day for a capacitor and the young man said that those thiningies are over there, so I walk over there now pissed and found drawers filled with mainly rca jacks and computer cables and to find about a dozen usless sizes and low voltage capacitors--I left and swore to never return.
:David



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