From Peter Sz per the 2008 red book from NTIA
Federal channels for shared use / common use - none of these channels are assigned to any one specific agency - the freqs can be used when there is no need for a specific authorized channel - (whatever that means in actual practice)
Countywide or statewide - repeater ops - transient use
163.1000R/168.3500 in
409.0500R/418.0500 in
409.3375R/418.3375 in
Countywide or statewide - simplex ops - bases and mobiles - no repeaters - wide area - transient
412.8250 412.8375 412.8500 412.8625 MHz
Local ops - common use - all federal users - repeaters
173.6250R/167.1375 in
407.5250R/416.5250 in
409.0750R/418.0750 in
Local ops - common use - all federal agencies - simplex - bases and
mobiles - no repeaters
168.6125 163.7125 412.8750 412.8875 412.9000 412.9125
I guess these freqs would be used for special short term operations -
maybe like county sharks in Chatham - or taking the census - or maybe
even for disaster teams - but since any fed agency could use them, I
am guessing that only low priority uses would prevail - possibly
nothing life or death - but who knows
