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37-620 Plate Resistor?
#2

That resistor looks like a decoupling resistor, used to isolate the power supply of the IF stage from the converter and RF stages. Sometimes if B+ power is applied to all stages from the same source, you may get instability or oscillations due to the common power source. The resistor, together with a bypass cap serves to filter the supply and isolate the stages from each other preventing the problem.

Most likely, the 10K value on the schematic was a typo, all to common on the Philco schematics. The plates of the 6K7 and 6A8 probably draw about 10 mA total, so there would be a voltage drop of 10 volts or so across 1K which seems reasonable. A 10K would give 100V of drop which would clearly be excessive.


Messages In This Thread
37-620 Plate Resistor? - by Vic Gibson - 08-30-2013, 08:21 AM
RE: 37-620 Plate Resistor? - by Mondial - 08-30-2013, 02:19 PM
RE: 37-620 Plate Resistor? - by Arran - 08-30-2013, 10:01 PM
RE: 37-620 Plate Resistor? - by Vic Gibson - 08-31-2013, 08:54 AM
RE: 37-620 Plate Resistor? - by codefox1 - 08-31-2013, 09:39 AM



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