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37-650 schematic discrepancy???
#1

My latest toy, a 37-650, worked great when I got it and now about 3/4 done with the resistors and caps and still plays great. Tag shows it was rebuilt in 1963, looks like a number of caps were replaced and a little wiring.

The problem is that I have a difference between the actual radio and the schematic at the volume pot. Looking at the schematic, part #40, a 75pf cap, is missing. What I have is resistor #41, 40k resistor is tied to cap #43 and the top of the pot, not to the center tap. Center tap is tied to cap #33. I did install a 75pf cap between top and center taps, but I cannot say it made any difference. The tone sounds great except the first setting almost sound like a pocket radio... normal for this setting??? The volume pot looks to be original, it is a 3 tap 2Meg.

Also in my output section, I have a resistor not on the diagram and looks like it was from the factory, it is between the junctions of parts #45, 46 and parts #47 and 53. I think it is a 330k ohm, any ideas why this is here? I left it in as the radio plays fine.

Thanks, Don

http://www.theoldradiofixerupperguy.com/...37-650.pdf


Messages In This Thread
37-650 schematic discrepancy??? - by raydog - 03-29-2014, 05:42 PM
RE: 37-650 schematic discrepancy??? - by raydog - 04-02-2014, 11:03 AM
RE: 37-650 schematic discrepancy??? - by codefox1 - 04-05-2014, 12:49 AM
RE: 37-650 schematic discrepancy??? - by raydog - 04-05-2014, 01:21 PM
RE: 37-650 schematic discrepancy??? - by Joeztech - 04-06-2014, 07:31 AM
RE: 37-650 schematic discrepancy??? - by raydog - 04-16-2014, 10:00 AM



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