On May 8, 9:29 am, Edward Knobloch wrote:
Rick (W-A-one-R-K-T) wrote:
Typically, can ham-bands-only receivers such as the Drake R4 and Collins
75A or 75S series, transmitters such as the Collins 32S and Drake T4
series, and transceivers such as Drake TR-4 and Collins KWM-2, be modified
to work on CAP and MARS frequencies?

The Collins CP-1 crystal pack provided general coverage HF operation
for the S/Line and KWM-2 equipment. A listing of available
operating frequencies is hehttp://www.collinsradio.org/html/s-l...cessories.html


There is a dead band that is not usable on these, 5 to 6.5 MHz. Also
you need a lot of xtals. Even with the expansion board you can only
have if I remember 30 of them.

There were external VFOs that provided all the possible frequencies
for both the xtal osc and the VFO. A Jaapanese company made one. I
think a service monitor will do as well if the output level is high
enough, most have programmable frequencies like scanners. I think if
the weight and size weren't prohibitive the IFR 1500 would be ideal
because it's available cheap and because it has full duplex unlike the
more common 1200/500 series. You could of course just use a sig gen,
again, assuming the level is high enough. No where in the Collins
manuals is the drive level needed specified!

I'm suirprised a digital internal VFO hasn't been devised for S-Line.