GMRS Base and mobile setup

I am looking to purchase three GMRS mobile radios and associated antennas that can be used in a vehicle or in a home. My requirement is to communicate with my two sons during a time of emergency. One son lives 6 air miles away and the other ½ air mile away and is located between the other son and me. The topology at my home and my closest son includes tall pine trees. We are located in Mandeville and Covington Louisiana, which is flat land, with no hills. I want to install a permanent antenna that could survive a hurricane-force wind. We have portable generators that could power the home setup when power is lost. We desire to use this radio in the vehicle if forced to evacuate. Looking at the Btech GMRS-50V2 mobile radio. A vehicle magnetic antenna and quick power connection to the vehicle are also desired. Looking at the UT-72 antenna, I am concerned that only a 50-watt mobile GMRS radio will communicate with my son’s 6 air miles locations. Understand I would need a power supply for my home application. I am on a retirement budget. Please advise. R/

There are lots of line of sight calculators on line - you enter the two points and it looks at the topograph and works out if it’s viable or not. Power has marginal impact on FM. Ten to twenty Watts may not even me noticeable - 10 to 50 will make the meter perk up a bit, but if there is no path, then no extra power will do much good.

Most radios today have plug in power cables - so you buy an extra one or two and fit these wherever the radios may be needed - on a power supply (mains to 13.8) that can sup-ply enough current. 15A is not enough when you go above 10-20W or so, so bigger (and more expensive) power supplies will be needed - another reason to not go too wild on power output.

Antenna wise - the taller the better, but with your weather, the taller, the more substantial the installation. You can often buy pretty substantial towers second hand, and the idea is to get them above local obstacles - if you have ridge lines, or tall forests, even huge towers don’t help that much.

My own experience with reliable systems is mainly with marine and commercial installs, and the key feature is that they are reliable and feature predictable performance. So a very tall, high gain antenna is NOT one I’d go for because the ■■■■ things are long and flex in high winds, and this reduces performance. Something stiffer, like those based on commercial designs might have lower gain, but will feature decent hardware that has long life and moderate repeatable performance. Low loss feeder into the building.

Don’t forget that you could always install two antennas - one an all round omni, but also a directional beam with lots of gain, and if you both have this - 6m is not likely to be an issue. You could even have a simple switch - directional and omni and use what is appropriate.

Cost wise - there is NO cheap fix - 3 radios, 3 power supplies, cabling, towers etc - will mount up. Only you know if this is sensible.

Alternative 2 is to get heavy duty brackets, thick walled tubing and get the antennas up that way. You know your weather best.

Being a Brit, and un-strung with radio rules, here, I’d buy a dual band cover everything radio for energency use - In a disaster situation GMRS is fine if there is somebody in range, but if life was at risk, then marine band, ham bands and even business radio would be fair game, and here, not an issue in a genuine emergency. The US folk who have things like Baofeng portables until recently were being bought for all kinds of uses. Now, you have an FCC requirement for them to be locked, but that’s a thing for you to decide. A 2m/70cm antenna based on the D-30 designs seems to match reasonably well on all get you out of danger frequencies. If you don’t have the budget, then you need to scour the 2nd hand market. What I would do however, is establish if the path exists. Perhaps by software, but why not borrow a couple of radios and try using them up a ladder both ends. If the path works on a few watts, you have a pointer.

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Hi August, welcome to the forum!
While not impossible, your scenario will require some careful planning and consideration to meet the requirements of your budget. I would suggest that you give us a call at 1-800-584-1445 or enter the live chat on our site for personal assistance with a member of our staff to help you figure it out. We’re here from 8 AM to 6 PM weekdays. For full disclosure, we own and operate this forum.


I think you can do it for sure, cost of the radios and base antenna will be the thing for you. You should definitely call Rick, above. The folks at BTWR are VERY helpful and that it is the best advice you’re going to get in this thread.

Thanks for the detailed info and recommendations. Will first try the line of site calculator. I am trying to not over-purchase but understand you get what you pay for.

for me, I found a deal, and got 1/4" hardline, 75ft, and 6db gain base antenna, working for me at 40ft, thought I have enought tower to put it up to 200ft, just don’t have the land to do it, much less the permit. I found in my years, of radios, the coax is a MAJOR key factor, if you don’t get it right, no different than haveing 4 watt portable