No surprises with the Calibrator … the design of this little enigmatic box has remained more or less unchanged since it’s inception.
It is also very easy to work on. It is often much maligned though as a ‘pig’ of a
circuit to get working. I’m no magician, but I have re-
Here is how I do it:
Obviously you need a working receiver. With the System switch set to ‘Cal’ tune the
KHz dial to a multiple of 100. 500 is a good starting point. Now adjust L69/70 (the
one furthest from VFO2) for an increase in noise or even a tone!. If L75 is not properly
set you are more likely to get noise rather than tone initially. Now adjust L75.
Generally you will hear a further increase in noise and then possibly a spontaneous
tone. It may be necessary to adjust the KHz setting too. If you don’t get a tone
it is likely that you have tuned one of the cores to a ‘false’ response. In which
case you just need to find the correct one by re-