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41-250 restoration
#7

Don't know if I would try to assess the osc frequency by using a scope to the control grid of the osc tube. The grid is a very sensitive to any outside influences by connecting to the grid you may be loading the circuit w/ resistance or capacitance from the scope, would cause some frequency shift or in some cases cause the osc not to operate.
Looking at it from the cathode of the mixer tube would be a better choice that's where the osc output is fed into the mixer.

As a practical matter when the set is set to receive the BCB the osc should be at 1005kc when the dial is set at 550kc and at 1955kc when the dial is at 1500kc. I try to keep it simple a 9v battery, $10 counter, and a small coil of wire. The 41-300 is tuned to KYW in Phily at 1060kc.


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When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
41-250 restoration - by keith49vj3 - 10-12-2017, 07:19 PM
RE: 41-250 restoration - by morzh - 10-12-2017, 07:43 PM
RE: 41-250 restoration - by keith49vj3 - 10-13-2017, 05:49 PM
RE: 41-250 restoration - by Radioroslyn - 10-13-2017, 06:40 PM
RE: 41-250 restoration - by keith49vj3 - 10-14-2017, 12:00 PM
RE: 41-250 restoration - by David - 10-14-2017, 12:28 PM
RE: 41-250 restoration - by Radioroslyn - 10-14-2017, 02:16 PM
RE: 41-250 restoration - by keith49vj3 - 10-14-2017, 03:04 PM
RE: 41-250 restoration - by Radioroslyn - 10-14-2017, 07:45 PM
RE: 41-250 restoration - by keith49vj3 - 10-15-2017, 04:10 PM
RE: 41-250 restoration - by keith49vj3 - 11-03-2017, 08:32 AM
RE: 41-250 restoration - by keith49vj3 - 11-03-2017, 08:34 AM
RE: 41-250 restoration - by morzh - 11-03-2017, 09:09 AM
RE: 41-250 restoration - by klondike98 - 11-03-2017, 11:11 AM
RE: 41-250 restoration - by KCMike - 11-03-2017, 12:08 PM



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