Red UNCAL light

NB : in focus mode the uncal light is always on !!

This error light can go on when using the synchroscan unit. The timebase runs sychronously with the 79 MHz (?) of the Mira laser, using a phase locked loop. If the frequency differs to much, the “SWR” Standing Wave Ratio (reflection/absorbtion) becomes to high, the time base stops and the red UNCAL light goes on.

The frequency can be adjusted with a little screw on the synchroscan unit, on the front, left, between the cooling ribs. It's difficult to adjust, maybe a plastic screwdriver is needed. Use it, to make the SWR as low as possible.
Best, first try it with timebase 2, and then switch to timebase 1.

If the synchroscan unit becomes warmer (mostly timebase 1), the SWR rises again.

Working stable with timebase 1, requires it to warm up for 1 hour : do not put it in 'Focus' mode, but keep it on 'Operate'.

Obviously, the trigger signal should be large enough (green led on the side should be on).