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Re: Lock light stays on


 

Yes, you need to fix those? mechanical issues first. It seems someone has really fiddled with this one
The kilocycle tuning capacitor needs careful setting up. With the vanes fully closed, the tuning shaft should be against the stop, and the tuning? indicator? should be aligned with the small triangle mark on the right hand side of the tuning drum.. The tuning cap is not used over its full travel, this is done to give a more linear readout on the scale.? It is normal for the tuning cap to not fully open, so perhaps this has not been changed.? This is a pain to get right, and you will need some very small allen keys to loosen the grubscrews if repairs are needed..
For completeness, the second VFO ,or kilocycle oscillator should be checked, it will run from 2.455 megs to 3.455 to give the 1 meg tuning increments.... and remember it actually tunes backwards.
Connecting your scope to TP109 should reveal a rising and falling waveform amplitude as the Megacycle knob is varied, but the scope will need to be a good one, this section is at 50 odd megs.
If you dont see any waveform here , the fault is either the amplifier chain or the harmonic generator. Sometimes the mixer chip will take a hit, but seldom.
Also check VR102 hasnt been wound fully on. This preset alters the bias on the LED lock lamp, It should go off at one extreme. This section rectifies part of the selective amplifier output signal to indicate correct tuning.

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