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City: Winter Haven, FL
What's happening here? The 6 meg tone control (51) is switched. That's why the dotted line. But the wiper can't be grounded, or the .01 cap, 40a, would just be shorted to ground. Why does the wiper have a circle for connection, instead of a dot? It appears the actual pot has nothing connector to the wiper. How does this tone control work?
I'm confused.
[Image:
https://i.imgur.com/e9jYt0n.jpg]
Posts: 15,704
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City: Jackson, NJ
It is correct.
The wiper simply brings GND closer to the C50, cutting out the treble, or further away, letting the treble through.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
(This post was last modified: 04-18-2020, 04:54 PM by
morzh.)
Posts: 365
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City: Winter Haven, FL
Got it. I'm getting old. I guess.
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Joined: Oct 2017
City: Allendale, MI
Well I have a question too! where does the phase inversion come from for the push pull? Does it come from the screen grid of the upper 41, through the .01 cap #52?
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City: Roslyn Pa
Yup...
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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City: Jackson, NJ
This is called "Paraphase inverter".
It is described here.
https://dalmura.com.au/static/Phase%20In...201948.pdf
Look at Fig. 10.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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City: Allendale, MI
Thanks guys! I like the line "results are disappointing..." I would think there would be some phase problems between the 2 output tubes, but I've never played with the circuit.
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