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Take a look at this photo. I'm sure this view is familiar to someone. You see those caps coming off of those two coils? The third one (to the left of those two) has been removed by the last guy. Since a replacement would be easy enough, (1) Was there a reason to do this? and (2) Since the radio seems to work fine, do I leave well enough alone? And (3) the two remaining are paper caps, .1, with a resistor, 100 ohm, inside and should they be replaced? (The chassis has been recapped.)
[Image: http://i191.photobucket.com/albums/z309/...79fc0d.jpg]
http://www.philcoradio.com/tech/images/87.jpg
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The reason probably was the capacitor either leaking grossly or shorting.
It is desirable to replace it as it is a decoupling cap, but it will work without it.
Now as to should you replace the other two....I would, as again, they are decoupling caps and are exposed to the raw power voltage, so if they go, they will possibly take something in the power supply (choke, field coil) with them.
Or you could try your luck.
Were they RC filter caps I'd say "if the radio works well, leave them", but in case of decouplers I am pro-active.
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Thanks.....is that 100 ohm resistor, part of these caps, anything special?
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Those decouple the RF to prevent oscillation. On my 87 all where leaking badly. What I did was cut the ground wire off of the old cap and solder in a replacement from the top lug and the other to ground. The new caps are small enough to hide under the old ones.
Good playing set when it's all fixed up!
Terry
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I followed your instructions and it worked perfectly. The radio sounds great. Thanks.
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I just restored a very similar radio (Philco 86) and it
had the same decoupling R-C networks (qty 3).
I chose to be pro-active and replace all three. I actually
removed them and replaced them with modern
100 Ohm resistors and modern 0.1 uF caps.
I saved the originals. Some day I may see if I can
clean out the center part where the old cap is and
replace it with a new cap. That would be the
best way to preserve the original "look".
Herb S.
Ithaca NY