A little table top Zenith I'm working on. 8C01 chassis. It works great but I decided it's time to swap out the old caps for new ones. This cap is C32 on the schematic. .022ufd. connected to the wiper of the volume pot. This looks like a standard old paper capacitor with one exception. One end of it not only has the normal lead sticking out but there is a little round terminal on the side of the cap that a wire is soldered to that goes to chassis ground. It looks like a capacitor case ground. I've never seen this before. Is the case of the cap being grounded and is this ground necessary? I was going to put in a standard .022ufd cap to replace it. The grounded end of the cap is the end of the cap that connects to the 19T8 tube. Can ya'all hep me? Thanks!
Johnny

:A little table top Zenith I'm working on. 8C01 chassis. It works great but I decided it's time to swap out the old caps for new ones. This cap is C32 on the schematic. .022ufd. connected to the wiper of the volume pot. This looks like a standard old paper capacitor with one exception. One end of it not only has the normal lead sticking out but there is a little round terminal on the side of the cap that a wire is soldered to that goes to chassis ground. It looks like a capacitor case ground. I've never seen this before. Is the case of the cap being grounded and is this ground necessary? I was going to put in a standard .022ufd cap to replace it. The grounded end of the cap is the end of the cap that connects to the 19T8 tube. Can ya'all hep me? Thanks!
:Johnny
:
:Sorry! NA does not have this schematic for you to view.I got my copy from "techpreservation.dyndns.org".

try a regular cap and see if you pick up noise. if you do you may need to fashion some kind of shield around the body of the cap

::A little table top Zenith I'm working on. 8C01 chassis. It works great but I decided it's time to swap out the old caps for new ones. This cap is C32 on the schematic. .022ufd. connected to the wiper of the volume pot. This looks like a standard old paper capacitor with one exception. One end of it not only has the normal lead sticking out but there is a little round terminal on the side of the cap that a wire is soldered to that goes to chassis ground. It looks like a capacitor case ground. I've never seen this before. Is the case of the cap being grounded and is this ground necessary? I was going to put in a standard .022ufd cap to replace it. The grounded end of the cap is the end of the cap that connects to the 19T8 tube. Can ya'all hep me? Thanks!
::Johnny
::
::Sorry! NA does not have this schematic for you to view.I got my copy from "techpreservation.dyndns.org".

Hi Johnny,
I have seen this before. It is shielding. On the Zenith 8H832's I have encountered them on, the shield was necessary, else the radio has a hum in the audio.

I solve the problem using capacitor stuffing. It is a delux restoration technique, where you remove the guts of the old capacitor by heating it in an oven at low temperature, about 150 degrees. Remove the guts of the old capacitor and put the new one inside. It is necessary here because of the shield.
Once the new capacitor is in you seal it with wax. My 8H832 has no hum at all.

Best Regards,

Bill Grimm

:Hi Johnny,
: I have seen this before. It is shielding. On the Zenith 8H832's I have encountered them on, the shield was necessary, else the radio has a hum in the audio.
:
: I solve the problem using capacitor stuffing. It is a delux restoration technique, where you remove the guts of the old capacitor by heating it in an oven at low temperature, about 150 degrees. Remove the guts of the old capacitor and put the new one inside. It is necessary here because of the shield.
: Once the new capacitor is in you seal it with wax. My 8H832 has no hum at all.
:
:Best Regards,
:
:Bill Grimm
:
:Well this is very interesting. I've already installed the new cap and now I'm anxious to finish just to hear this hum. Just as a test. I've still got the old cap and you say I can heat it as described and use the outer shielding? I'm gonna do this.
Thanks,
Johnny

:Hi Johnny,
: I have seen this before. It is shielding. On the Zenith 8H832's I have encountered them on, the shield was necessary, else the radio has a hum in the audio.
:
: I solve the problem using capacitor stuffing. It is a delux restoration technique, where you remove the guts of the old capacitor by heating it in an oven at low temperature, about 150 degrees. Remove the guts of the old capacitor and put the new one inside. It is necessary here because of the shield.
: Once the new capacitor is in you seal it with wax. My 8H832 has no hum at all.
:
:Best Regards,
:
:Bill Grimm
:
:Hi Bill. I finished the recap and I heard no hum except when I turned the radio off. There was a hum that sounded more like a burp. Turned it on again and then off and it did it again. Tried it again and then nothing happened. I'll keep an eye on this before I close it up. I have some material that is copper sleeve. Very fine mesh. Would this work as a shield if carefully applied around the cap and then grounded to the chassis? The stuff on the old cap is just too aged and is pretty much falling apart as I try to remove it.
Johnny

:A little table top Zenith I'm working on. 8C01 chassis. It works great but I decided it's time to swap out the old caps for new ones. This cap is C32 on the schematic. .022ufd. connected to the wiper of the volume pot. This looks like a standard old paper capacitor with one exception. One end of it not only has the normal lead sticking out but there is a little round terminal on the side of the cap that a wire is soldered to that goes to chassis ground. It looks like a capacitor case ground. I've never seen this before. Is the case of the cap being grounded and is this ground necessary? I was going to put in a standard .022ufd cap to replace it. The grounded end of the cap is the end of the cap that connects to the 19T8 tube. Can ya'all hep me? Thanks!
:Johnny

Johnny: They are right on, it is shielding. Being an old Zenith dealer I can tell you that Zenith used these in verious locations with radios, TV's, and phonos.
I solved the problem by simply winding a layer of small magnet wire (#24 or so) over a new capacitor and grounding one end of the coil. Good luck on your project.