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I think we are confusing adjustments here. The adjustment for demodulator quadrature phasing is done by first shorting the green and blue control grids to ground through 100K resistors. You must use a gated rainbow generator to make the adjustment. Adjust L125 until the sixth bar in the gated rainbow to matches the background. Then after removing the blue grid resistor and then grounding the red control grid through it, adjust T115 until the third and ninth bars blend with the background. I have done these adjustments and it works: it is to ensure the quadrature demodulator is accurately aligned.
The AFC adjustment does indeed suggest grounding the reactance tube grid and adjusting for zero beat. This is only to set the 3.58 MHz oscillator to precisely lock.
However, that leaves the chroma bandpass amp: that is to be sweep aligned. Is that what you require?
Last edited by Penthode; 01-19-2012 at 10:33 PM.
Reason: To clarify my statement
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