This post was sent to me by Dave Eherenman, and I thought others might be interested:

The General Mobile Radio Service (GMRS) is a land-mobile FM UHF radio service designed for short-range two-way voice communications.  It is higher power and has both handheld and base-station units than the walkie-talkie type Family Radio Service(FRS) radios.  GMRS operation does require you to obtain an FCC license, and so you must identify yourself (station) by saying your FCC assigned “call sign” at the end of a transmission session (or a series of transmissions sessions), and at least once every 15-minutes for a session lasting more than 15-minutes; FRS does not.

Usable range is greatly enhanced with an external antenna mounted on your RV (due to higher antenna height than is possible with handheld units).  Antenna height is your friend: the higher, the better.  I attached my external antenna towards the top of my ladder, but made sure the tip of the antenna is < 13’ 6” for bridge/tree clearances (Eastern States).  At home when you’re free of moving obstructions, you can legally go up to 20’ in height.

Like FRS, GMRS has 22 frequencies (i.e. channels) to choose from (excluding repeater frequencies).  The big plus though is that GMRS may transmit up to 50-W on channels 15-22 whereas FRS is limited to only 2-W.

The current impasse on GMRS RV growth is that we - the RV community - have yet to gravitate to a common channel for our road travels (analogous to CB’s channel 19).  Also to be honest, there’s a little bit more to it than just one common channel agreement, since every radio manufacture sets-up a different privacy (squelch) code per channel…  But since we want to be able to collectively communicate, I disable the privacy code when traveling (and it’s just me, but I monitor Channel 20).

If you’re still interested, here’s some top-level URLs to further your reading pleasure:

- Wikipedia à https://en.wikipedia.org/wiki/General_Mobile_Radio_Service

- RV GMRS à https://forums.mygmrs.com/topic/2450-gmrs-for-rv-community

- GMRS Radios à Google “GMRS Radio Reviews”

- GMRS “Privacy Codes” à https://forums.mygmrs.com/topic/3669-understanding-privacy-lines-subchannels-tones

- YouTube à Anything with “GMRS” in the search string

and the list is endless…

Dave Eherenman

FMA #9012 / FMCA #F540260 / GMRS call-sign “WSDC766”