Quote:
Originally Posted by Techman
Did we find out what Q17 and Q18 did, or is it still a mystery?
Or perhaps I need to have a closer look at the diagram/s.
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No mystery, not an afterthought, they are the mixer for the receiver. Two J-FETs in a single-balanced configuration. The wanted signal comes in through an RF amplifier with varactor-tuned frequency as a preselector, then operates the two JFETs as a balanced amplifier. But the gate voltage of the JFETs is fed via the centre tap of the input transformer secondary and is the receiver local oscillator from the synth.
David