[Collins] 70K-2 PTO coil

[James Miller]

Consider this possibility:  What would happen if someone accidentally
misconnected the coax cables between a 32S3 and 75SB such that the
receiver PTO cable is accidentally connected to the 32S3 RF output or
some other source of high voltage/current?  What would happen to the PTO
output coil?   I had to troubleshoot a 75S3 mixer coil that got fried by
some previous owner for the same reason probably.  Probably connected
the xtal osc. coax to the wrong RCA connector!  A sudden and unexplained
reduction in sensitivity on one band!  I rewound the mixer coil in the
75S3.  You can probably rewind a PTO output coil as well.  Good luck and
watch where you plug those RCA connectors!  Jim N4BE

"Dr. Gerald N. Johnson, electrical engineer" wrote:
> 
> Perhaps the KH6 more humid climate speeds the demise of the coils. I
> didn't find my spare PTO to look at the coil, though the parts list
> gives inductances as measured two ways. Perhaps a Navy manual will give
> coil winding instructions. Likely the coil is wound with something like
> #38 or 40, I presume on a slug core, not a toroid. Not wire sizes that
> are easy to work without the proper tools but with the right tools not
> impossible to work with.
> 
> Because of lingering corrosion from solder flux, I suspect the coil
> failure to be at the terminals, not within the winding.
> 
> How is the coil constructed?
> 
> 73, Jerry, K0CQ, Technical Advisor to the CRA.
> --
> Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
> Reproduction by permission only.
> Sponsored by the Collins Radio Association
> http://www.collinsra.com