Quote:
Originally Posted by DaveWM
There was also a burnt resistor, a 33k that goes from the 145 B+ to the cathode of the audio out, then 180 ohms to ground. Its forming a voltage divider at the cathode (145+,33k,cathode,180,ground) but not sure why its done that way. Anyway its smoked and now its replaced.
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That was a trick to create a lower B+ voltage for the tuner and IF strip, and so as to not waste power when doing that voltage drop, that otherwise wasted power was put to use as the audio output stage. The audio output tube current was effectively put in series with the total current drawn by the tuner and IF tubes.