Quote:
Originally Posted by Tom9589
Therefore, the cathode of the 2nd stage is way above ground and would need the extra transformer.
Now that begs the question: Why did they make those two IF stages in this unusual configuration?
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It looked like a "smart" way of getting over the problem of dividing the B+ to run the IF amplifier. It was typical in those days for the B+ from the rectifier to be in the order of 350VDC. The signal chain would need only half that. Early RCA design featured divider resistors which got hot and burned out. Others provided +125 to +140VDC from the cathode of the audio output tube with the plate at +350VDC.
Motorola used this approach. Unusual but quaint.