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Old 05-13-2011, 08:42 AM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by wa2ise View Post
The audio output tube is providing the 150V source, via its cathode. This effectively puts the audio output in series with the IF strip, in a sense the plate current gets used twice. Instead of burning power thru a dropping resistor to get the 150V, the audio output circuit becomes the equal to that dropping resistor.
Just about every large manufacturer of TV sets did that. If the set used a 6W6 or a 6AS5, 6BF5. They refered to it as "stacked B+". The tubes would short real easy, if overloaded.
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