16L cap confusion - Printable Version
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16L cap confusion - Patrick - 07-24-2019
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]
RE: 16L cap confusion - gregb - 07-24-2019
I am pretty sure that cap is .3uf and two .15uf in parallel would make sense.
Gregb
RE: 16L cap confusion - Patrick - 07-24-2019
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.
RE: 16L cap confusion - Radioroslyn - 07-24-2019
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
RE: 16L cap confusion - Patrick - 07-24-2019
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?
RE: 16L cap confusion - Patrick - 07-24-2019
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.
RE: 16L cap confusion - Radioroslyn - 07-24-2019
>Wonder what's next?
Oh maybe a bad IF transformer or open shadow meter...
RE: 16L cap confusion - Patrick - 07-24-2019
Shadow meter's good. Done tested it. Haven't checked the IF's yet. Eventually.
RE: 16L cap confusion - Radioroslyn - 07-24-2019
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