Quote:
Originally Posted by Boater Sam
Good guess Al, but cathode is grounded! Another cost reduction measure.
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Bit more that a 'cost reduction measure': that's a design failure.
The lack of a fixed bias means that when signals from the aerial reach a certain magnitude and the AGC applied to the mixer is overcome, the grid of that I.F. valve will be driven +ve. By adding an R in its control grid, in effect, that is same as introducing a small -ve bias on strong signals.
Al.