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?

Many will reach the CAP and MARS frequencies at the edges of the
dial.

You can usually make small frequency shifts through modification,
but most ham receivers of the boat anchor class used very frugal
mixing schemes that carefully placed major spurious responses outside
of the ham bands.

Operation around the VFO frequency, or the first IF frequency will usually
not be very nice.

Crystals are readily available from Jan, or ICM. Google is your friend.

-Chuck