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My Philco 18 is recapped, aligned and sounds great. I did skip one bakelite block, though. It's a .00011 twin block that comes off of the secondary of the 2nd IF. Not having any 110 pfds on hand, do I just ignore this one?
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(04-15-2012, 04:27 PM)DKinYORKpa Wrote: My Philco 18 is recapped, aligned and sounds great. I did skip one bakelite block, though. It's a .00011 twin block that comes off of the secondary of the 2nd IF. Not having any 110 pfds on hand, do I just ignore this one?
I guess if it were me,I would want to do it right.
I have gotten pretty good at re-building those.
Caps are readily available.
Have a great day.
murf
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Quote:I guess if it were me,I would want to do it right.
......OK, I just ordered some.
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Is 110 pfd critical or can a 100 pfd or a 120 pfd be used as a sub?
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These two caps are the hi freq audio filter, many times called a "tweet filter."
A standard value for a dipped silver mica cap is 110pf and readily available at many part suppliers and vendors. Close enough is also fine if you are not picky. The cap/resistor filter cutoff freq is in no way critical.
Chuck
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If it's a pair of micas inside it may be alright to leave alone, the values are small enough to be micas. I opened up a Philco Bakelite block condenser once that had micas inside. If you do need to replace them then you can also use precision ceramic caps, I've used those a few times in various things.
Regards
Arran