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16L cap confusion
#1

On the attached schematic, cap number 86, which is across the choke (filament of 5Z3), is indicated as a .5 mfd. However, the parts list says it is a 6287-F, which is a double bakelite .15 mfd cap. Which one is correct, or does it make much difference? Thanks,

Pat

[Image: https://i.imgur.com/l9N0XuZ.jpg?1]
#2

I am pretty sure that cap is .3uf and two .15uf in parallel would make sense.

Gregb
#3

That would make sense since I can't find another #86 on the schematic. However, when I look at the bakelite block (without disassembling it), there were 3 internal connection on it, and no 2 of them are tied together. If it were 2 .15mfd in parallel, there should only be 2 internal connections.
#4

Here's how mine is wired. There is no jumper across the to end terminals but the ohm meter sez it's a short. Black wire must be connected over to the spkr somewhere.
>If it were 2 .15mfd in parallel, there should only be 2 internal connections.
Not necessarily Philco probably used that block in other application where it two .15's rather than a single .3mfd. This wouldn't require a jumper.

GL


Attached Files Image(s)
   

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
#5

Now I'm even more puzzled. Wonder where the black wire went? The way yours is wired, there's only a .15 across the choke?

This 16L is a lot of fun. First, the field coil was open and not repairable (used a U3 with a 10W 300Ω in series - hope that works - U3 has a 1150Ω field coil, U2 has a 1450Ω coil), then the input transformer primary is open. But I disassembled it and found the broken wire, so I'll repair it. Now the minor cap problem. Wonder what's next?
#6

I know, the black wire and the "to speaker and 13K resistor" must be tied together somewhere. That would make the two .15 in parallel.
#7

>Wonder what's next? 
Oh maybe a bad IF transformer or open shadow meter...

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
#8

Shadow meter's good. Done tested it. Haven't checked the IF's yet. Eventually.
#9

I also read that the 10k qavc pot is subject to failure. Was fine in mine. IF's are probably ok mine just had a wiring problem. OPT sometimes is an issue. Short of these it's pretty straight forward.

GL

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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