Model 650 Tone Control Question
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Joined: Dec 2009
City: Roslyn Pa
Heathkit got a deal on those 12BY7's. Back in the mid 1950's they use them as the audio driver tube for the modulator section in their 100 watt class AM transmitter the DX-100. P/P1625 (12v 807's) which will make about 120w class ab2. It's transformer coupled and is grid biased from the hv power supply. You'll note that there are two 1/10 of an ohm resistors in the cathode circuit of the 1625's. These are not for biasing but are meter shunts.
https://archive.org/details/heathkit_dx-100_manual
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
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RE: Model 650 Tone Control Question - by Radioroslyn - 07-13-2023, 06:07 PM
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