10-09-2017, 10:28 PM
That schematic give me a headache!!
I did find one for a 46-350 121 that's clean but doesn't use that locktol output tube. Any way I think there is a misprint on your schematic as I can see why if there is 74v on the plate there's 72v on the cathode (filament). that's on the 3lf4.
Methinks your 680 ohm (R-207) resistor is a problem. Shouldn't be see any ac voltages around those directly heated tubes.
I did find one for a 46-350 121 that's clean but doesn't use that locktol output tube. Any way I think there is a misprint on your schematic as I can see why if there is 74v on the plate there's 72v on the cathode (filament). that's on the 3lf4.
Methinks your 680 ohm (R-207) resistor is a problem. Shouldn't be see any ac voltages around those directly heated tubes.
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