[R-390] Collins 390 zero adjust knob problems.

[Harold Hairston]

Bob;

I sure hope that you get an answer to this R-390A dilemma (And I am sure 
that you will) as I experienced a similiar problem over the weekend with my 
R-390A that I use every day. My problem is with both "Calibration Knobs" 
that worked ok last time I tried to calibrate the unit. Seems that I can not 
lock the unit mechanicallly so that I can put the PTO on the 100 KC point.

Let me tell you what I do know about this matter. My "Operator's Manual" Has 
a Hand-Written note (Change C-2 ?) that cautions the user not to force 
either the Dial Lock or the Zero-Adjust past their stops in either direction 
nor to turn the Kilocycle Knob if the Dial Lock is in locked position., else 
damage may occur to the unit.

If you receive replies direct, please pass them on.

Harold