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37-620 Mystery Part - Value?
#1

http://www.nostalgiaair.org/PagesByModel...013212.pdf

I have a question about part 34, listed as a 400 ohm bakelite resistor. It is in the cathode of the IF amplifier. What is installed (and appears original - in fact ALL parts of the radio are original) is a flexible resistor with code RED, BLACK, BROWN (body, end, dot). If this were a normal resistor it would be 200 ohms. But I don't know if the codes for flexible resistors are the same. It measures 810 ohms - likely too high. The value is stable (does not change when the resistor is moved).

So what should I replace it with? Leave it (value is correct), or 400 ohms per schematic, or 200 ohms(?) as installed?

As an aside, the cathode bypass capacitor, part 35, is listed as .05 in the schematic AND the parts list. But a 0.25mfd capacitor (a Philco part, 30-4446S) is installed, and looks all original - no signs of any servicing being done. So perhaps there have been some changes made to this radio?

Any advice would be appreciated.


Messages In This Thread
37-620 Mystery Part - Value? - by davemc - 01-23-2011, 05:37 PM
Re: 37-620 Mystery Part - Value? - by Ron Ramirez - 01-23-2011, 10:01 PM
Re: 37-620 Mystery Part - Value? - by davemc - 01-24-2011, 02:36 PM



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