[Collins] R-390A filter

[Dr. Gerald N. Johnson, electrical engineer]

My 390A manual is too far down the piles to be found or retrieved. As is
the CD-ROM with the manufacturing drawings.

There is a R-390 reflector where everyone there knows everything about
the innards of the radio. I'm remembering that the mechanical filters
were 8, 4, 2, and 1 KHz bandwidth, then the narrow filter was an audio
filter, not crystal filter in the A. My 390A is harder to access than
the manual and could take years. The 390 was all together different in
the IF and selectivity.

To understand and maintain the radio you will need the entire manual.

73, Jerry, K0CQ, Technical Advisor to the CRA
-- 
Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.