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Philco 3630 wire wound
#1

http://pacifictv.ca/schematics/philco219manual.pdf

I recently bought this Philco 3630 and started to go thru it and found that Part #70, the wire wound resister doesn’t check out properly. The first section tests at 21 ohms which is good but the second section which is supposed to be 263, tests at 25 ohms. Can someone tell me what value resister(s) and wattage I would require to replace either both sections or just the section that’s off.

I have never had to this in my short time in this hobby and any assistance would be appreciated.
#2

Well I figured the problem out. The e-cap shown in the green circle was replaced some time ago and was shorting to the chassis. I wrapped some paper around it to isolate it and the wire wound tested perfectly at 263 ohms. You have to love his candy stripe wire! Live and learn.


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#3

Ah yes...replacement e-caps with the can (or negative lead) to ground when they're not supposed to be...it is a more common problem than it should be. Many "repair" people in the past would go ahead and "fix" the set, without consulting the schematics.
#4

Yes;
The negative side of one condenser is supposed to be connected to the center tap of the high voltage winding, and not the chassis, that is the most negative point in the B- side. A lot make this mistake with replacements because most post war radios had their audio output stages self biased, via a resistor in series with the cathode of the power output tube or tubes, the set will hum like mad as a result. In this case it looks like a previous "repairman" stuffed a pair of twist lock condenser cans in the old clamps, and did not know what the cardboard sleave was for. You should see what some hacks did to house wiring back in the day.
Regards
Arran




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