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Philco model 84B Cap ?
#1

Hey, I have a Philco 84B I'm working on and have a Bakelite Condenser question.
http://www.nostalgiaair.org/pagesbymodel...013875.pdf
 Part #24 .006 7625-H which crosses to 7625-SU .006 cap sections 1&3.
This part is wired with the cap (.006) between 2&3. The tar has not been disturbed and the #1 post has never had solder on it. Is this common? Should I make it like the instruction or just wire it as I have found it?
#2

If I'm reading it right, the schematic only shows one line in and out (between a 490k resistor and the power transformer), so it probably doesn't matter which posts you use?

Greg

"We are here to laugh at the odds and live our lives so well that Death will tremble to take us."
#3

Greg,
 what I'm saying is the numbers in the Philco Bulletin #289 which has all the blocks and the caps and how they are configured is not what I have. Just opened up another block #20 witch has a .001 & .015 the instruction shows them connected with the #1 being common and in this case ground but the schematic shows only the .001 going to ground. Now the print shows that making the #2 pin the common pin putting them in series. I will go by the schematic I think. Thanks  Icon_question Icon_question
Eric
#4

I have come across bakelite caps that were not wired the same as the 289 bulletin.  I do not recall if it was the 84 I was working on or not but it may well have been. Looking at the underside of the 84 I did both before and after the recap I think the #20 bakelite (the one on the far left of is wired as follows:

[Image: https://www.dropbox.com/s/uns61cpqg2oczq....jpg?raw=1]

You can also see that the #24 bakelite (just to the right of the #20 cap) in my set also had the 0.006 cap between leads 2 & 3. You can see the #23 resistor (in my case a 490k) connects to lead #2 of bakelite #24 and lead #3 connect to the plate of the 42 tube (and thus is the other end of the 0.006).

Fun isn't it... Icon_crazy
#5

Yes that  is correct the .001 connects from the 10K resistor to gnd. The ungrounded side of the .001 is the audio signal coming out of the detector stage. The .015 blocks the dc voltage supplied to the detector thru the 10k resistor so you don't have a high + voltage on grid of the 42. The other end connects the audio signal the the control grid of the 42.

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 it!

Terry
#6

Had #20 wired wrong went and did it per your drawing and verified it through the schematic. The person before me just added caps on top of the filter caps without disconnecting them from the old. They also just added caps on top of the bakelite blocks so is was quite a rats nest.
The tubes all check good and the voltages look good and I'm using about 30' on antenna and I get the 2 big stations here in the Atlanta area. Next up is an alignment.

Thanks for the help!




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