HP 339A oscillator problem

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Sorry to hear of continuing troubles.

TP2 obviously not working, highly probable TP1 not working either. It you'd like to trouble shoot without resorting to component removal, we try.

As a check for at least partial opamp health, try measuring U3B (i.e.TP1) by using meter probe to join pins 7 and 6 simultaneously. This will produce unity gain and you should see 0V on meter if that opamp section is operable. Try same procedure at U5B.

If these checks look good, would you report opamp U3C voltages at +,-, and output pins, and Q1 base and emitter voltages? Similary, U5D and Q2?
 
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