Philco 41-280 Capacitor

9/10/2007 11:10:03 AMTex

This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?

9/10/2007 1:47:44 PMLewis Linson

:This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?

Yes, red is positive, and black is negative, but....
According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
I will do some more checking and get back to you.

Lewis

9/10/2007 2:07:34 PMLewis Linson

::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
:
:Yes, red is positive, and black is negative, but....
:According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
:I will do some more checking and get back to you.
:
:Lewis

You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.

Lewis

9/10/2007 2:11:13 PMLewis Linson

:::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
::
::Yes, red is positive, and black is negative, but....
::According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
::I will do some more checking and get back to you.
::
::Lewis
:
:
:You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.
:
:
:
:Lewis
:
Oops, phone rang and I left out half of "resources"

I had some storm damage to my house caused by a neighbor's dead tree, and I am in the middle of a fight between his insurance company and mine over who is going to pay for repairs. I am getting ready to kill an adjuster. Will you guys be on my jury??

Lewis

9/10/2007 2:31:50 PMMarv Nuce

Lewis,
Find an "ADJUSTER" to adjust the adjustor.

marv

::::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
:::
:::Yes, red is positive, and black is negative, but....
:::According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
:::I will do some more checking and get back to you.
:::
:::Lewis
::
::
::You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.
::
::
::
::Lewis
::
:Oops, phone rang and I left out half of "resources"
:
:I had some storm damage to my house caused by a neighbor's dead tree, and I am in the middle of a fight between his insurance company and mine over who is going to pay for repairs. I am getting ready to kill an adjuster. Will you guys be on my jury??
:
:Lewis

9/10/2007 3:11:42 PMTex

I don't think the cap that I took out is an electrolytic, when I touch the wires with an ohm meter the meter doesn't move. It looks like a big paper cap, the number on it is 30-2474-X. I can't find any 12uf caps in the catalog.

:Lewis,
:Find an "ADJUSTER" to adjust the adjustor.
:
:marv
:
:::::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
::::
::::Yes, red is positive, and black is negative, but....
::::According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
::::I will do some more checking and get back to you.
::::
::::Lewis
:::
:::
:::You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.
:::
:::
:::
:::Lewis
:::
::Oops, phone rang and I left out half of "resources"
::
::I had some storm damage to my house caused by a neighbor's dead tree, and I am in the middle of a fight between his insurance company and mine over who is going to pay for repairs. I am getting ready to kill an adjuster. Will you guys be on my jury??
::
::Lewis

9/10/2007 3:51:21 PMBill VA

It's an electrolytic Tex, my junker -287 has the same but it has plus symbol on end with red lead. I won't try and post a pic Edd! To Lewis, as I understand nowadays insurance companies have aligned and your homeowners kicks in in this situation. But I could be wrong. A reciprocal thing.
Bill

:I don't think the cap that I took out is an electrolytic, when I touch the wires with an ohm meter the meter doesn't move. It looks like a big paper cap, the number on it is 30-2474-X. I can't find any 12uf caps in the catalog.
:
:
:
:
:
:
::Lewis,
::Find an "ADJUSTER" to adjust the adjustor.
::
::marv
::
::::::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
:::::
:::::Yes, red is positive, and black is negative, but....
:::::According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
:::::I will do some more checking and get back to you.
:::::
:::::Lewis
::::
::::
::::You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.
::::
::::
::::
::::Lewis
::::
:::Oops, phone rang and I left out half of "resources"
:::
:::I had some storm damage to my house caused by a neighbor's dead tree, and I am in the middle of a fight between his insurance company and mine over who is going to pay for repairs. I am getting ready to kill an adjuster. Will you guys be on my jury??
:::
:::Lewis

9/10/2007 4:22:19 PMLewis Linson

:It's an electrolytic Tex, my junker -287 has the same but it has plus symbol on end with red lead. I won't try and post a pic Edd! To Lewis, as I understand nowadays insurance companies have aligned and your homeowners kicks in in this situation. But I could be wrong. A reciprocal thing.
:Bill
:
::I don't think the cap that I took out is an electrolytic, when I touch the wires with an ohm meter the meter doesn't move. It looks like a big paper cap, the number on it is 30-2474-X. I can't find any 12uf caps in the catalog.

The only cap you should have connected to the control grid is the coupling cap to the stage before it, perhaps .01 or .1 uFd, that should not be an electrolytic. As far as 12 uF, most any value will work, that cap is for filtering out the ripple that is left after the 84 does its rectifing thing. Higher Voltage and/or higher capacity will work just fine in that case.

According to Georgia insurance law, if my neighbor's tree is alive and it falls on my roof, it is an Act of God, and I am responsible for the damage. If the tree is dead (which it very much was), my neighbor is negligent, and therefore he is responsible. Since we both are insured, we turned our claims over to our insurance companies, who are fighting tooth and nail to get out of paying. My neighbor and I remain the best of friends.
Lewis
::
::
::
::
::
::
:::Lewis,
:::Find an "ADJUSTER" to adjust the adjustor.
:::
:::marv
:::
:::::::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
::::::
::::::Yes, red is positive, and black is negative, but....
::::::According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
::::::I will do some more checking and get back to you.
::::::
::::::Lewis
:::::
:::::
:::::You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.
:::::
:::::
:::::
:::::Lewis
:::::
::::Oops, phone rang and I left out half of "resources"
::::
::::I had some storm damage to my house caused by a neighbor's dead tree, and I am in the middle of a fight between his insurance company and mine over who is going to pay for repairs. I am getting ready to kill an adjuster. Will you guys be on my jury??
::::
::::Lewis

9/10/2007 4:58:24 PMBill VA

::It's an electrolytic Tex, my junker -287 has the same but it has plus symbol on end with red lead. I won't try and post a pic Edd! To Lewis, as I understand nowadays insurance companies have aligned and your homeowners kicks in in this situation. But I could be wrong. A reciprocal thing.
::Bill
::
:::I don't think the cap that I took out is an electrolytic, when I touch the wires with an ohm meter the meter doesn't move. It looks like a big paper cap, the number on it is 30-2474-X. I can't find any 12uf caps in the catalog.
:
:The only cap you should have connected to the control grid is the coupling cap to the stage before it, perhaps .01 or .1 uFd, that should not be an electrolytic. As far as 12 uF, most any value will work, that cap is for filtering out the ripple that is left after the 84 does its rectifing thing. Higher Voltage and/or higher capacity will work just fine in that case.
:
:According to Georgia insurance law, if my neighbor's tree is alive and it falls on my roof, it is an Act of God, and I am responsible for the damage. If the tree is dead (which it very much was), my neighbor is negligent, and therefore he is responsible. Since we both are insured, we turned our claims over to our insurance companies, who are fighting tooth and nail to get out of paying. My neighbor and I remain the best of friends.
:Lewis

Lewis, would you believe I was going to add after "reciprocal thing" to beat the insured people!Left it off trying not to be so skeptic. I know about them pecan trees in Georgia...no matter where the nuts fall they belong to person who has the tree. Or has it changed.
Bill
:::
:::
:::
:::
:::
:::
::::Lewis,
::::Find an "ADJUSTER" to adjust the adjustor.
::::
::::marv
::::
::::::::This radio has a cap marked 12mfd, it doesn't have the polarity marked, the red wire goes to pin #4 of the #84 tube. The black wire goes to pin #4 of the #41 tube. Can I use a 10uf electrolytic & connect the positive to the red wire & the negative end to the black wire?
:::::::
:::::::Yes, red is positive, and black is negative, but....
:::::::According to the "Tubes" section above, pin #4 of the 41 tube is the control grid, no capacitor of the electrolytic persuasion orta connect there at all.
:::::::I will do some more checking and get back to you.
:::::::
:::::::Lewis
::::::
::::::
::::::You have a capacitor from pin #4 of the 84 to the center tap of the power transformer, and another to the screen of the #41 tube to the chassis ground, or one on each side of the speaker field coil. There are some biasing resistors between the center tap and the chassis ground, about 190 Ohms worth. If you are unhappy with the increase in hum caused by the lower 10uF cap, go buy a 12, but I don't think you will notice any difference. Again, Positive to pin 4 of the 84 and 3 of the 41, negative to the transformer center tap and chassis ground. I had to use the (121)drawing to get the power supply, I assume the 41-280 is very close to it. I forgot the colors of the center tap, it will be in the urces section above.
::::::
::::::
::::::
::::::Lewis
::::::
:::::Oops, phone rang and I left out half of "resources"
:::::
:::::I had some storm damage to my house caused by a neighbor's dead tree, and I am in the middle of a fight between his insurance company and mine over who is going to pay for repairs. I am getting ready to kill an adjuster. Will you guys be on my jury??
:::::
:::::Lewis

9/10/2007 7:04:03 PMThomas Dermody

The item you show in the picture is most likely an electrolytic. It has probably dried up, which might be why you get no reading on your ohm meter. Be sure to use the most sensitive setting (X10,000). 12 MFD should certainly deflect the meter for a moment. Lewis says that you should have a 'lytic going from the cathode of the '84 to B- and another from the screen grid of the '41 (pin 3...remember which way the pins are oriented when looking at the underside of the receiver....they are usually the same as the view shown in a tube manual, or on this site) to B-.

Perhaps someone altered the wiring, or perhaps you are not orienting your socket numbering correctly. Be sure to follow the original schematic carefully.

Thomas

9/10/2007 10:17:39 PMLewis Linson

:The item you show in the picture is most likely an electrolytic. It has probably dried up, which might be why you get no reading on your ohm meter. Be sure to use the most sensitive setting (X10,000). 12 MFD should certainly deflect the meter for a moment. Lewis says that you should have a 'lytic going from the cathode of the '84 to B- and another from the screen grid of the '41 (pin 3...remember which way the pins are oriented when looking at the underside of the receiver....they are usually the same as the view shown in a tube manual, or on this site) to B-.
:
:Perhaps someone altered the wiring, or perhaps you are not orienting your socket numbering correctly. Be sure to follow the original schematic carefully.
:
:Thomas

Sir Thomas (et al.)
The schematic shows one 'lytic right at the rectifier cathode, and the other at the screen of the output tubes, with the speaker field in between. I makes perfectly good sense to use the tube sockets as tie-points for the caps, the second cap going to the screens of the output tubes to chassis.
Maybe somebody didn't count the pins correctly? It's easy to forget to count CW and CCW for up and down. It has happened to me once or twice (or three times or four times or.......)

Lewis

9/11/2007 12:12:42 PMThomas Dermody

Yes. It could be that he miscounted pins or something. You are right about capacitor location, though.

9/11/2007 1:26:51 PMTex

I think I threw you off when I said that the black wire went to #4 of tube 41, I was tracing the wire to its end. I should have said that the black wire goes to a binding strip, then to another binding strip then to a 1meg(I think)resistor, then to #4 of tube 41. I do have a 20uf from #3 of 41. I have replaced all the caps except the bakelite one. When I plug the radio into the dim bulb tester it glows slightly even with a 100w bulb. Should I go ahead and give it full voltage?
:Yes. It could be that he miscounted pins or something. You are right about capacitor location, though.
:
:T.

9/11/2007 2:05:21 PMLewis Linson

:I think I threw you off when I said that the black wire went to #4 of tube 41, I was tracing the wire to its end. I should have said that the black wire goes to a binding strip, then to another binding strip then to a 1meg(I think)resistor, then to #4 of tube 41. I do have a 20uf from #3 of 41. I have replaced all the caps except the bakelite one. When I plug the radio into the dim bulb tester it glows slightly even with a 100w bulb. Should I go ahead and give it full voltage?
::Yes. It could be that he miscounted pins or something. You are right about capacitor location, though.
::
::T.

Each pin #4 of the 41 tube should go to a 1meg resistor. The other end of the resistors should connect together and go to the Green-Yellow wire out of the power transformer. This point should also go to Item 62, 12 uFd. negative side. The other side of item 62 should go to pin #4 of the 84 tube. This pin should also go to the speaker field coil. The other side of the speaker field coil should go to the center tap of the output transformer, and item 27A, 16 uFd., the other lead of which connects to chassis ground. Between pin #4 of the 84 and chassis ground, or the negative side of the 'lytics, should be three resistors that appear to be item 61, for a total of about 200 Ohms to chassis ground.

Lighting up a 100 W bulb dimly sounds good, go for full power and see what happens. Let us know.
Lewis

9/11/2007 3:24:02 PMTex

I traced the wiring that you mentioned, it seems to be correct. The radio had an 8mf, 12mf, & 20mf when I got it, I used two 10uf & a 22uf. The radio comes on but doesn't play, it has only a bit of static from the speaker when turning the knob that changes from BC to Shortwave. I checked the tubes they all tested good, but the 84 only showed 56.

::I think I threw you off when I said that the black wire went to #4 of tube 41, I was tracing the wire to its end. I should have said that the black wire goes to a binding strip, then to another binding strip then to a 1meg(I think)resistor, then to #4 of tube 41. I do have a 20uf from #3 of 41. I have replaced all the caps except the bakelite one. When I plug the radio into the dim bulb tester it glows slightly even with a 100w bulb. Should I go ahead and give it full voltage?
:::Yes. It could be that he miscounted pins or something. You are right about capacitor location, though.
:::
:::T.
:
:
:
:Each pin #4 of the 41 tube should go to a 1meg resistor. The other end of the resistors should connect together and go to the Green-Yellow wire out of the power transformer. This point should also go to Item 62, 12 uFd. negative side. The other side of item 62 should go to pin #4 of the 84 tube. This pin should also go to the speaker field coil. The other side of the speaker field coil should go to the center tap of the output transformer, and item 27A, 16 uFd., the other lead of which connects to chassis ground. Between pin #4 of the 84 and chassis ground, or the negative side of the 'lytics, should be three resistors that appear to be item 61, for a total of about 200 Ohms to chassis ground.
:
:Lighting up a 100 W bulb dimly sounds good, go for full power and see what happens. Let us know.
:Lewis

9/11/2007 7:05:37 PMLewis Linson

:I traced the wiring that you mentioned, it seems to be correct. The radio had an 8mf, 12mf, & 20mf when I got it, I used two 10uf & a 22uf. The radio comes on but doesn't play, it has only a bit of static from the speaker when turning the knob that changes from BC to Shortwave. I checked the tubes they all tested good, but the 84 only showed 56.

The 84 is a rectifier, and testing those things doesn't really tell much about the tube. Having static or noise in the speaker when the band switch is changed is an excellent sign that the power supply and the audio is working. Now would be a good time to take the transistor radio and tune it to a blank space at the high end of the dial, then tune your Philco around on the low end of the dial appx. 455 KHz below the transistor. You should be able to find the local oscillator. This should tell us which fork in the road we need to take next.

Lewis

9/12/2007 10:57:01 AMTex

::I traced the wiring that you mentioned, it seems to be correct. The radio had an 8mf, 12mf, & 20mf when I got it, I used two 10uf & a 22uf. The radio comes on but doesn't play, it has only a bit of static from the speaker when turning the knob that changes from BC to Shortwave. I checked the tubes they all tested good, but the 84 only showed 56.
:
:The 84 is a rectifier, and testing those things doesn't really tell much about the tube. Having static or noise in the speaker when the band switch is changed is an excellent sign that the power supply and the audio is working. Now would be a good time to take the transistor radio and tune it to a blank space at the high end of the dial, then tune your Philco around on the low end of the dial appx. 455 KHz below the transistor. You should be able to find the local oscillator. This should tell us which fork in the road we need to take next.
:
:Lewis
:
I put the transistor near the Philco & set the transistor between stations on the high end, I moved the Philco up & down the dial but didn't hear any sound.

9/12/2007 7:19:21 PMLewis Linson

Now, it looks like you might have a local oscilattor problem. Without a LO, you aren't going to get anything else working. I'll need to study your schematic and see what to do next.
Lewis

9/11/2007 3:16:20 PMThomas Dermody

If the binding strip lug that it goes to connects to the chassis, then that lug is actually B-. It is coincidental that pin 4 of the '41 connects there as well, via a 1 meg resistor. Both circuits need that voltage reference point, and the terminal of the binding strip you talk about was the convenient place to connect them both. The center tap of the power transformer H-V winding most likely also connects to the chassis. If everything is connected as you say it is connected, then all is well.

9/11/2007 4:18:15 PMRadiodoc

Thomas,

I think the binding post he is referring to is a terminal of the wirewound resistor 61 on the schematic. The input electrolytic cap's (62) plus connects to pin 4 of the 84 tube and the minus connects to the ungrounded end of resistor 61 (146/31/15 Ohm) and transformer high voltage centertap (green-yellow wire). The negative voltage at that junction is fed to the grids of the 41 tubes thru a couple of 1meg resistors.

Radiodoc
************

:If the binding strip lug that it goes to connects to the chassis, then that lug is actually B-. It is coincidental that pin 4 of the '41 connects there as well, via a 1 meg resistor. Both circuits need that voltage reference point, and the terminal of the binding strip you talk about was the convenient place to connect them both. The center tap of the power transformer H-V winding most likely also connects to the chassis. If everything is connected as you say it is connected, then all is well.
:
:T.

9/11/2007 5:12:04 PMBill VA

:Thomas,
:
:I think the binding post he is referring to is a terminal of the wirewound resistor 61 on the schematic. The input electrolytic cap's (62) plus connects to pin 4 of the 84 tube and the minus connects to the ungrounded end of resistor 61 (146/31/15 Ohm) and transformer high voltage centertap (green-yellow wire). The negative voltage at that junction is fed to the grids of the 41 tubes thru a couple of 1meg resistors.
:
:Radiodoc
:************
:
::If the binding strip lug that it goes to connects to the chassis, then that lug is actually B-. It is coincidental that pin 4 of the '41 connects there as well, via a 1 meg resistor. Both circuits need that voltage reference point, and the terminal of the binding strip you talk about was the convenient place to connect them both. The center tap of the power transformer H-V winding most likely also connects to the chassis. If everything is connected as you say it is connected, then all is well.
::
::T.

9/12/2007 1:09:07 AMThomas Dermody

Ah. Much better....a schematic. That clarifies everything.

9/12/2007 11:01:30 AMTex