{Collins} 75A-1 trimmer capacitor repair/replacement


I am in the process of getting a 75A-1 back on the air and found a number of
trimmer capacitors in the tuneable IF and front end are either jammed or
broken (will turn but no change in capacitance or intermittent with


I have spent a few hours searching the reflector and the Collins site but I
haven't found exactly what I am looking for.  I am hoping someone can


1.       Can the trimmer caps that no longer tune be repaired or do they
need replacing?

2.       Is there a source of replacement caps (sorry I had to ask) or ones
that fit the mounting holes and chassis opening?

3.       It looks like the various front end "modules" and variable IF
stages are attached by 3 screws (each) through the main chassis.  Removing
the screws, and wires going to the tubes plus the rotary switch shaft should
enable the modules to be removed for repair.  If there is a simpler way I
would appreciate knowing what this is.

4.       If 3 above is roughly correct, I assume the rotary switch shaft is
removed by removing the front panel, removing the two nuts holding the front
switch mechanism to the chassis and pulling the shaft out the front of the
receiver?  If this is not the way to do it, could someone let me know the
correct procedure.


Thanks and regards,




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