I found myself needing to shut off the RF Tx on an ePTP Master (non-GPS radio) to prove or disprove an interference situation.
Stupid question... how? You can't set the frequency to None like Canopy. It won't let you save the config. Seems stupid to have to switch to SM or SA mode just to turn off an AP/BH.
I vote for allowing no carrier frequencies to disable Tx with a quick save like a normal frequency change.
Might try changing it to a frequency in DFS band, there should be a lot of availability there.  Just be careful of TDWR frequencies 5615 and 5645 for you.