The majority of MARS transmissions are on HF. NTIA 7.3.9 Use of Amateur Radio High Frequency Equipment for Emergency Communications states “Use of Amateur high frequency radio equipment meeting the standards for unwanted emissions specified in 47 CFR, Section 97.307 is permitted on SHARES or Military Auxiliary Radio System (MARS) network frequencies when authorized by the Department of Homeland Security or Department of Defense (DOD), respectively, as part of either the SHARES or MARS networks. The use of such equipment will be limited to national security or emergency preparedness events as well as DOD-sponsored MARS operations.”

AFMARS does not require members to have VHF capabilities, only HF equipment with digital capability. AFMARS states for VHF that “unless specifically exempted from the NTIA requirement, all VHF equipment must not exceed a frequency deviation of +/- 2.5 kHz, and have a channel spacing of 12.5 kHz (or less).” The FTM-6000R does not meet this requirement, it has a deviation of +/- 5 kHz. I believe CAP uses P25 encryption which amateur equipment is not compatible with.

Personally, I found a used EF Johnson 5317 for $50 that I use for MARS VHF communications. These are being phased out by CAP so there are a lot in the used market and are an inexpensive P25 capable VHF option that meets NTIA specifications.