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37-630 code 125 missing all 110 pF caps
#18

Hi SD Radioman,

Getting off topic is what we do best.

If the caps are not there, it won't harm anything. However, do check the wiring of the 2 diodes in the detector / 1st AF amp. In the schematic, one diode connects to the secondary of the 2nd IF transformer, the other diode connects to the first diode via a 100pF cap. The alternatives are that the diodes are merely connected to each other and to the transformer or only one diode is connected to the transformer, and the other one is grounded.

Unfortunately, in the world of electronics and especially for antique radios, changes happen within runs that are not documented. However, you can either add the caps per the published schematic or not. If you find the sound too harsh and the issue is not the Audio section, add the caps per the schematic. (Add a "Radio / Aux switch at the input of the volume control to evaluate the amplifier section and to and enjoy Old Time Radio from your computer without the distortion that modulating / demodulating causes.) If the diodes are connected together or one diode is grounded, don't bother changing that part of the circuit.

Hope this helps.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


Messages In This Thread
RE: 37-630 code 125 missing all 110 pF caps - by MrFixr55 - 03-31-2026, 01:06 AM



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