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37-630T RF and IF grid 3
#1

grid 3 of the RF 6K7 tube is grounded thru a resistor. but grid 3 of the IF 6K7 tube is connected to ground thru a wire with little resistance that's wrapped around the secondary of the first IF transformer. my radio is a code 125-126, schematic attached. meanwhile, in a different 37-630 [no code], grid 3 on both the RF and IF tubes is simply grounded thru a common resistor. this design seems to be more common. which leaves me wondering why the grid on mine is coupled to the IF transformer. anybody know? or know what difference it makes.


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.pdf 37-630t schematic.pdf Size: 585.94 KB  Downloads: 170


Messages In This Thread
37-630T RF and IF grid 3 - by fenbach - 07-21-2022, 04:01 PM
RE: 37-630T RF and IF grid 3 - by RodB - 07-21-2022, 05:08 PM
RE: 37-630T RF and IF grid 3 - by fenbach - 07-21-2022, 11:05 PM
RE: 37-630T RF and IF grid 3 - by Ron Ramirez - 07-21-2022, 11:27 PM
RE: 37-630T RF and IF grid 3 - by RodB - 07-22-2022, 02:50 PM



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