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We use GMRS when headed out for camping. I have a 25 watt mobile in the truck pulling the 36’ fifth wheeler. The wife has an HT with a roof top external antenna in her Grand Cherokee towing our boat. We get excellent range in the Adirondack mountains. Once in camp I carry an HT and she’s always got one close at hand. A few other campers have them but since we camp exclusively in parks with no hookups, we don’t see a lot of radio use. Ham radio is much the same way where we go. I am hoping to add a solar powered repeater this year. That may encourage other GMRS folks to join in.

The R1225 UHF repeater came in 2 versions. A Low Power model starting with model # M04GRC***** and a Higher power version model starting with M44GRC***** The lower power version will do 1-10 watts - and do it with nearly a 100% duty cycle. Those units have a smaller heat sink on the back of the transceiver, and rarely had problems with burning up, even with heavy use. Many people used those for on-site use with Portable radios, or for driving a power amplifier to achieve higher wattage power outputs with a higher degree of reliability in high duty cycle applications. The high power versions were rated as being 50% duty cycle at 40 watts, and 100% duty cycle at "mid power" settings of 20-25 watts. Those units commonly burned up - especially if someone tried to run them at 40 watts with anything approaching 5 minute conversation times. The higher power models did have a much more substantial heat sink on them, but you still needed to have good airflow if you wanted to run them at even 25 watts for any period of time. I've seen those units burned up even when run at the lower power levels that were advertised as 100%. Motorola should never have sold the higher power version at any level above 25 watts, and they should have said even then that it was a 50% duty cycle IMHO. I would be VERY careful buying a GR1225 off Ebay if I didn't know the seller or the source of the unit. Make sure it works and transmits with advertised power! Make sure the seller accepts a return if it doesn't. The amplifiers can be repaired, but its done wrong as often as it's done right. The cost to repair a burned up unit at the local radio shop would probably equal or exceed what you paid for it.

Here is where you can generate "maps" of your expected coverage based on the data you enter. This program will also consider topographic data. The 'green' areas are predicted HT @ 70% reliability, the 'yellow' areas are mobile coverage @ 70% reliability. This was for a proposed repeater to be located near Schaumburg, IL. Unfortunately, after a detailed site survey we determined that there would be to much potential for conflict with all of the other repeaters on the 150' tower. https://www.ve2dbe.com/rmonline_s.asp

Hey All, see $SUBJECT Navy ET in a previous life, Ham for the last 20 or so (KG4MBU) although not active the last 10. Started looking into GMRS as an alternative to CB for overland trips (2 and 4 wheels). Found you guys, got my ticket, looking to learn more and hopefully contribute when I can. Thanks for providing this space!

Hey 527 here with a reminder that this weekend is amateur winter field day. I recommend that we link up as much as reasonably possible and give users an opportunity to make some contacts over the weekend... QSO party! Please weigh in, make suggestions and key up! wrcu527 Darren in Tucson

All radios are Motorola or Motorola/Vertex. VX-261 EVX-S24 EVX-534 XPR6550 XPR7550 Michael WRHS965 KE8PLM

Thanks you Radioguy, the radios have arrived. What a wonder opportunity. 7 radios, 5 different models. I will report back my findings to this group pending completion of my evaluation. Michael WRHS965 KE8PLM

I'll issue a pre-emptive welcome to GMRS. It's a great community, especially here. Hopefully you'll get your license soon. I have a 27-foot Forest River Wildwood and always use my handheld GMRS units for several reasons when camping, but not for the reasons you stated (or at least I haven't done so yet). My wife lets me know I'm screwing up when backing into a site with the radio. A few feet makes a huge difference as you know and by the time I hear her shouting or she dials a phone a tree could be in the trailer living room. I also take a lot of photos in some remote regions after nightfall and before dawn. A two-way is the ideal solution if an emergency arises, assuming I haven't ventured too far. When we caravan with the son-in-law radio beats even bluetoothed phones in the trucks because it's faster if you need to alert the person behind or in front of you. There's something of an official GMRS channel for roadside emergencies, I think Ch. 20, but I'm confident someone here will clarify or confirm. I also contact owners of repeaters near where we are camping to secure permission to use their repeater in an emergency. As you know, cell phone service stinks at some campsites, but if someone has a repeater on a mountain nearby you can punch a signal out to summon help. That's critical in my case because my daughter is a quadriplegic and the first trip with our trailer the state park locked the gate at 8 p.m. and there was no cell service. We were instructed to drive to the check in station in an emergency and use an outside landline to call 911 in an emergency....when sometimes it's not prudent to abandon the victim, even temporarily. I think your idea is great, though and I'd sure be game to help start a trend (although I have my doubts with Smartphone addiction today). The traffic/weather report idea, though, is sort of like truckers with CBs. There's some propagation differences that shorten most transmissions, but there's also none of the trash talking on GMRS...well, exponentially less anyway. So have you posed your question on any RV/trailer groups? If not I'll post it on the Forest River groups I belong to. Not sure if the admins will delete it, but I'm sure interested.

Makes sense thank you!

If your going to use the crank up antenna I used the laird as I do now on my 5th wheel. I mounted it with the brackets that come in the kit but had to add an extension to get around the AM/FM antenna. I followed the same "entry" as the TV antenna but spent way too much time trying to fish it down the wall. In the end it looked nice, let me crank up antenna and was on air, but had to use RG58 and had about 30'. It also knocked out the TV apparently only when the wife was watching . I had it on the repeater first then ended up moving it to my midland radio as a "base" in the unit. When we got the MH I didn't want to deal with all of the wire stuff which is why i got the FG4500. Mounted on the motorhome with the cable run down the ladder along frame rail to the compartment made it simple and effective. Its about an 1" taller than my vent covers and most of the time have left it in place even while traveling. I did remove it originally thinking it would get hit but so far its been fine. In reality if it gets hit I already hit my vents and other stuff on the roof. But again its a 2 minute job to remove it. Inside the MH I have the Midland 275 on the dash hooked to a NMO mount in the center of the MH. I removed the factory AM/FM antenna and put a thick mount NMO with a 12" stainless disk under it. It works perfect. 99% of the time its just talking to the repeater anyway but when I'm traveling down the highway its nice. Depending on your camper your roof will be rubber coated or fiberglass. Neither will give you any ground plane so you will need to add it. Also its a sandwiched roof inside layer, foam, outside so trying to mount an antenna on it is challenging. You could just screw a piece of steel on over the rubber and use a mag mount but that leads to other issues. Getting a cheap base antenna is probably the best bet without alot of work. IF you have solar the other option may be to use a L style mount on the Solar mounts. I did this on my fathers MH but he only uses it to talk to me when we are traveling.

The wording I have seen from the FCC doesn't prohibit business use - but it does say something about "Coordinating Licensee's activities". I've seen plenty of Family Farms using GMRS. A Mall that's using a non-identified Repeater on GMRS frequencies is probably NOT a "grandfathered" activity. From what I recall, those entities that received GMRS authorizations back in the day were things like AAA traffic assistance, REACT groups, and Town Watch organizations. Have you done a search of the FCC's website in your local area for that Frequency? If they're legit, you should find a license on the frequency, even if it's held in some other entity's name (Like an operating company for the Mall). In your particular scenario, I'd be tempted to put one of my repeaters on the 462.xxx output frequency and match their PL/DPL. Then I'd start ID'ing with Morse Code every 15 minutes (with PL!) If they're a legit user, you should get a phone call pretty quickly. If they're not legit, they'll go away soon enough. Hopefully they would get a real License on an IG business band frequency.... but there's probably a reason they didn't do that to start with.

I just picked up a GR1225 for $300 and power it to 25 watts for family at home then move it to RV and Jeeping. This new purchase can run on standby 12 volt battery and trickle charge off of 110v plus I have solar charging in RV as well as an inverter that I will plug it into. O and in the RV site plugged in... so not running battery dry. So my two KG-805G working off our family repeater will really work well for us. Jack

I took your advise in reverse.... even you did not give it... I just picked up a GR1225 for $300 and power it to 25 watts for family at home then move it to RV and Jeeping. This new purchase can run on standby 12 volt battery and trickle charge off of 110v plus I have solar charging in RV as well as an inverter that I will plug it into. O and in the RV site plugged in... so not dry like you are talking about. Jack

This has been sold, Thanks for looking

Since UHF is essentially line-of-sight, you will often find you run into obstacles well before power becomes an issue. BTW, if you really want a 50 watt transmitter be prepared to pay for it.. There is a huge difference between a 50 watt mobile and a repeater with the same power rating. The difference is duty cycle. Your mobile will probably run around 0% much of the time, and then maybe 50% if you are in a conversation with one other station. However, the repeater can run at 100% duty cycle for long periods. Try that with your mobile and you will fry/melt the finals.

Also note that this is theoretical. I have a repeater mounted about 30' up. Going north, it loses signal about 3 miles out due to a large hill in that direction. To the south I easily get 8-10 miles reliably, and I've had reports of people reaching the repeater nearly 45 miles away from me, though only in particular spots. Terrain isn't the only issue that reduces range. Large buildings, high voltage transmission lines, and high RF environments tend to further diminish signals unless professional grade stuff is used. One thing I will say is if you get a flat pack duplexer, be sure to upgrade that first before switching to larger antennas. I found that each repeater I set up that started with flat pack duplexers, even the high quality ones like Celwave, often saw a 20-40% increase in range. I also found that by using 25W instead of 40W that the repeater seems to get the same range while being able to detect weaker signals from portables at longer distances.

I agree. I have a Ham Radio buddy that got permission, yes it's possible, several times to use his HT on a commercial jet flight. There was a bit of a pile up when you're talking 500 to 1000 miles radius from 30,000 feet on FM.

There are some online programs to show you range. As said above height and antenna gain is everything. You can put 50 watts out on your garage roof and not talk as far as 5 watts on a 2500' mountain top.