Freqs used by the PRC-90 are 243.0 MHz and 282.8 MHz.
243.0 is an International Air Distress frequency and is what you get when the Guard channel is selected on a military radio. That freq isn't going away any time soon and is monitored by any military radio w/ Guard selected.
282.8 is UHF SAR COMMON is a discreet freq to take SAR related comms off the guard freq.
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Better is the Enemy of Good Enough.
Okay, what’s your point??