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40-195 Restoration
#16

Looking at the last photo it looks like you may have replaced one of the paper caps with another paper cap. The pink tubular cap appears to be a Sangamo molded paper, in which case it is probably as bad as the waxed paper one you replaced. That specific one appears to be a coupling cap to the output tube grid and is very critical as to leakage, which could destroy the output tube, transformer, and more.

Those plastic molded paper caps haven't been made in 60 years and go bad by themselves from age. It would be a good idea to replace this cap, along with any others you may have installed like it with modern film caps.


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#17

Good morning Mondial,

You are correct, that is one I did not replace as I have not run into one of those before and opted to hold off until I could research it and replace it with the correct resistance. Based on the schematic, I believe it is #68 which is listed as a .005 mfd. 

Can you confirm? 

Thank you!

On a side note, I notice you are from NY. Written on the back of this unit is a company from NY which I believe was where it was originally purchased.
#18

I am still learning to read the schematics and this one is not that easy. Looking at some videos and images people have posted that it does not seem exact to mine. In fact a lot of the same model Zeniths I have worked on that still have factory components are just a little different. I guess that goes to the manual manufacturing of the day when everyone put their own experiences into it.

Will take a look at what you suggested and hopefully find some more data.

Thanks again!
#19

Yes, it looks like cap #68 is the pink one and can be replaced by a .005 uF 630 V film cap.
#20

Replaced! Thank you
#21

   

After pulling it out and softening the tar like substance, I was able to remove the 2 capacitors. Based on what I am seeing in the schematic it looks like there are 2 - .01uf capacitors that are there. I could not tell how they were connected, but I would imagine they both have a lead in the center and the other lead goes to the top and bottom. That make sense?

Since I do not have x2 that is .01uf, time to order a couple, the lowest I have is .047uf. 

This all provided an opportunity to put some shrink tubing on the cloth wires that were sketchy!


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#22

Both new capacitors will connect to the end terminal with the big ground lug, the other terminal of one cap connects to the center and the second cap to the opposite end.
#23

   

Just to confirm ....
#24

Yes, that is correct.
#25

   

So on the OPT there are 2 large wires and 2 smaller ones. I am guessing that 2 go to the field coil     and the other 2 go to the voice coil. I cannot tell which one is which on the speaker connector based on the schematic. 

Looking at the picture the red and white wires I have there go to the smaller wires and I image should go to the voice coil while the other 2 wires will end up going to the field coil. 

Does that make sense?
#26

Perfect. I will install them on top in the event I ever have to replace them. Seems a whole lot easier that having to remove the wires and replace them.

Thank you for the help.
#27

Hello VintageRocks,
Far as your speaker connects and it's plug goes my 1940's General Electric Console has looks to be almost the same plug style .
I need to replace my original wires on my plug your set is coming right along .

Sincerely Richard
#28

Did some research last night and found that the FC is inside the heavy magnet at the top of the speaker and the VC is the one with the thin wires that go to the cone of the speaker. That helps with where each is located, now to trace the wires so they are going to the correct terminals in the chassis.
#29

   

Example of what I found
#30

There's 2 other things that are important. The FC connects between the two electrolytic caps in the power supply circuit. The VC connects the secondary of the output transformer.
If you look at the VC and the opt circuit on the schematic you'll see something that looks odd. The VC is facing one way and just below there's another coil facing the other way. This coil is placed on top of the FC and is completely separate electrically. It's called a humbucking coil and it bucks hum do to it 's out of phase relationship w/the VC and it magnetic field from the FC

Geez your going to be a rocket scientist after you get this project done.[Image: https://philcoradio.com/phorum/images/icons/smile.gif]

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry




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