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The more I learn about the FCC's General Mobile Radio Service (GMRS), the more I am fascinated by RF in general. It touches everyone's lives every second of every day, yet few people pay much attention. How cool is it that after 42 years and 14 billion miles away, the 22-Watt radio on Voyager 1 is still sending data back to earth every day (how important is that antenna?). So why aren't more people interested in GMRS or RF in general? There's no test to get a license like amateur (ham) radio. It's $70 for a 10-year license, and is really easy to get started. So here are some theories. People don't know: GMRS exists Why GMRS exists Why they'd want to use GMRS How to envision themselves participating in GMRS What it takes to get started with GMRS What it takes to continue and improve with GMRS Technical information they should know about GMRS Etiquette when transmitting (TX) on GMRS What a GMRS "Net" is and why Most people within the GMRS community are helpful once you're in, but the community is very inviting in a go-figure-it-out-yourself way, and no one has assembled everything you need to know about GMRS all in one place. We GMRS people are putting the onus on outsiders to sift through thousands of painfully esoteric webpages with a winnowing fork, separating useful info from useless, poorly written, or incomplete info. When I first heard about GMRS on a 4x4 trip, I arrived home and Googled around and settled on a Midland MXT-275 because it seemed perfect for mounting on my truck dashboard. At the time, I had no idea that Midland doesn't manufacture a GMRS radio capable of operating on split-tone repeaters (Dear Midland, I know you're reading this: why do you squander so much potential?). Edit 6/28/2021: Midland heard our cry! They just updated the MXT-275 to include split-tone programming on repeater channels. So for example, now this radio is able to reach a repeater that receives (RX) incoming transmissions on 467.550 with a PL tone of 103.5 and repeats the transmission (TX) at 462.550 with a PL tone of 88.5. I didn't even know what "split tone" was or even what "tone" meant, or carrier or squelch or hundreds of other little things you all take for granted. Since then, I realized that if the big, bad manufacturers like Midland, Kenwood, Motorola, and iCom can't even invite the public to learn more and provide useful content for each stage of the customer journey—Awareness, Consideration, Purchase, and Loyalty—the 2-way radio industry has much deeper problems and aren't there to help guys like me. As we get involved deeper into GMRS, there's little-to-no hand-holding going on at each level of knowledge. I ending up relying on the Ham community here and there and a guy who is basically a saint at a little radio shop in Phoenix, Arizona (hope Tim over at Procomm and the others at the nonprofit AZGMRS.org don't mind me giving them a shout-out). Edit 4/14/2020: By the way, AZGMRS made this awesome list of FCC-approved GMRS radios that they recommend. If you live anywhere near Arizona and are reading this, now would be a great time to become a member. Their repeater network covers some 100 miles around Phoenix with more and more repeaters joining the network (check out their sweet coverage map). But it's still frustrating. I wish a GMRS expert—presumably a manufacturer—would just come out and say exactly what a total newbie needs at each stage of their involvement or level of need. Two-way radio manufacturers should stop wasting time trying to sell, and start marketing and branding, which means educating the public about the 5 W's (Who, What, Where, When, Why [+how, +how much]) without trying to sell to them. Most new users don't know what they need because they don't know what's possible. For example, I wish I knew that manufacturers don't typically include the best antenna on their radios right out of the box. It took me over a year to realize that the best bang for the buck for a portable base antenna to include in my go bag is N9TAX's Slimjim and that Smiley Antenna makes the best bang for the buck antennas for hand-held radios (which by the way, everyone just assumes newbies are supposed to know that hand-held walkie-talkie radios are called "HT" for "Handy-talkie" and what a "QSO" is). How would a newbie know that the cheap Nagoya 771 "upgrade" antenna for Baofengs that everyone talks about actually isn't the best bang for the buck for the GMRS frequency band of 462–467? How would a newbie know that antennas work best when tuned exactly to what they call a "center" frequency that accommodates 5 Megahertz in each direction (+5 and -5 Megahertz) at the expense of hearing other frequencies? I learned the hard way that in order to properly install an NMO antenna mount on the roof of my truck, I would need a drill bit specifically made for drilling NMO antenna mount holes, and that yes, it is worth the money to do it right the first time. I'm still in the middle of learning how a "quarter-wave" or "5/8 wave" antenna works, the difference between dB gain vs. dBi gain, mic gain, antenna gain, because again, everyone seems to just assume I already know what all this means. I still don't understand what antenna "tuning" means and why you have to "cut" an antenna to "tune" it. Can I make my own antenna right now in a pinch with a copper wire in my garage? Ok, show me! How do I measure it or test it? What is SWR? Can I measure it myself? What do I need in order to measure it? Is one SWR meter better than another for my level as a newbie? Is there something I should learn to make it worth buying the better meter that opens up a whole new world of capability? Is it worth learning all that? This graphic did a great job beginning to explain what dBd gain means for those of us who know next to nothing about it, but now I need to go find out on my own and sift through a thousand webpages to find out if dBd is something new I need to know. Speaking of dB, I know that "dB" is a decibel, but is it the same as my stereo volume? Why do I see manufacturers saying that the microphone and cable have a dB rating? What is going on here? This is madness! We can Google things all day, but which info is true and correct and the most helpful? I think that the entire industry is sitting on a Gold Mine of consumers sitting at home for weeks on end who would love to buy GMRS equipment and communicate via GMRS to friends, family, neighbors, and other GMRS users. Whoever provides the most useful, relevant, and engaging content that stops making assumptions about what people know or don't know will win. STOP ASSUMING. START EDUCATING.

There is no public download (That I know of) at this time. This is to avoid confusion with the ham radio side of Asterisk. Ontop of this, you will also need a username/password for the server, and I believe the linked network is limited to repeaters only (to avoid unlicensed FRS users from accessing repeaters through the 462 frequency) If you have the equipment already, you can contact Rich@MyGMRS.com and he can get you set up with the image and username/password. If you do not have the equipment, you can purchase it from https://shop.mygmrs.com/products/repeater-linking-bundle?variant=32248678744099 and choose an interface that will work for your radio.

I have a few Ebay seller which I got my equipment from radios, programming cable to repeaters: Bluemax49ers: Programming Cables-Got all my cables from him reliable very helpful guy. bargain_broker (email Bill Keenan online shop:usedtwowayradios.com): Mototrbo's and Repeaters erac1 (Used-Radios.com): iCOM, Kenwoods, Motorolas, Vertex and Harris Repeaters etc.

Thanks, I will give it a try

Thanks! I agree with terrain dependant with regards to coverage on the North side I only managing 7 miles max due buildings and elevation while in the South side of the repeater 16-18 miles since this is an less building elevation is lower and mostly plain along a Toll way. I have received my EVX-R70 and another good buy very clean unit likes new I will alternate this with the 8300, my next project will be the MTR's I know SLR's are the future but it's too expensive at the moment.

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HHmmm, Well, you will have a few options. The legal way, (And if you plan to be a relay station between GMRS and Ham) would be to get two separate radios, one (preferably dual band) for ham, one for GMRS. If you go this route, I would say the TK880 low power (25W) would be a good start. With a power supply and proper wiring for RACES, you can make that radio swap from a vehicle to your house to a command post and will give you a legally dedicated part 95 radio for GMRS use. They typically go for about $60 on ebay. Youll need a programing cable ($10-20) and software (can be found for free) If you have a little more cash on hand the Motorola XPR4350 covers both 70CM HAM and GMRS bands at about $175. This radio is part 90, and will give you DMR options for the ham bands (if there is a local DMR repeater near you this would likely be a better option) If you would like a lesser legal way, and I am not supporting this, though in an emergency it will work, is to get a reasonable ham radio (I used a yaesu 7900) and have a cap mod done which allows the radio to transmit out of band. This would give you both 2M and 70CM ham bands and access to the GMRS band though I would only run low power to prevent too much interference. Next you'll need coax. If your only doing 20-30 feet, RG8x will be fine. Longer lengths and you may wish to find better coax. I used LMR200 for some time at about 60 feet and found it was reasonable, however that observation is irrelevant as your install situation will be different from mine. Being you'll likely eventually have several radios in the shack, you may wish to consider the LMR200 just to prevent inductance (I think thats the proper word, basically signal from one radio getting into the another radio through coax run very close to one another) For antenna's, again, it will vary by install. A friend of mine runs a browning unidirectional antenna at about 20' up and has shown good results with low SWR. I have a couple antennas, One Tram hi-gain antenna for the repeater at 25-30' up and it gets about 6 miles range, and another being a diamond 200U which in the same install configuration only had 3 miles range. The use of the antenna also will change what type you will want to use. My understanding is that the higher gain antennas are more for repeater use, while lesser gain are better for mobiles and portables. Im in no way an expert on this and am just going by the experience I had when starting out. Most of the comms stuff you learned in the past will cross over here. Use your best judgement, and if you have a question ask and you'll usually get an answer rather quickly.

I just realized I never posted the final configuration of my base station antenna. I ended up building a tilt-over mast with a simple 1/4-wave ground plain up at 27ft AGL fed with about 55ft of DRF-400 coax running to the radio. I have tested the base to HT range with my Midland GXT 1050's and can get at least 5 miles to the HT if I am not in a low spot. I have also been able to hit a repeater over 50 miles away that was LOS. I also am able to hit my local repeaters in my local Front Range GMRS group. So basically I did my research online, took excellent advice from this group, did my calculations and that, with a little bit of luck, managed to exceeded my original requirements. EDIT: Added a photo I neglected to the other day. John ];')

Frequency coordination is not really official. They really have no power to stop anyone from doing anything. All the FCC cares about is interference between users. FACT, if someone has a parked frequency pair, for amateur radio, but it's not used, and you put up a repeater, the FCC will not give a damn. If there is no interference, there is no problem. frequency coordinators do not own the frequencies. If they file a complaint with the FCC and there is no interference, the FCC won't care. To the person who wondered if DMR will work on GMRS, of course it works just fine. In fact, if DMR is ever adopted, it will greatly expand the use of GMRS. But FCC is always making sure that changes are backward compatible. Fact is DMR would reduce a lot of interference. That's what it's designed to do, and you get double the capacity, if not more. Two conversations can take place simultaneously on the same frequencies. Regarding how long it takes to transmit a text. This example is "I'll be headed home soon". It was transmitted in DMR message, into a dummy load, and i real time speed. You can hear the beep, when the message was sent. msdsite.com/DMR/dmr.mp3 But being legal is an entirely different matter.

Several members here have done so. Search the forums for reports. There seem to be three issues that are commonly reported and which may, or may not, be important to you. The Midland radios operate on narrow-band FM while most repeaters operate on wide-band FM. This tends to result in the Midland's broadcasts being heard at a lower volume by listeners. The Midland radios must use the same tone or digital squelch on transmit and receive. So, if you have a repeater that uses different schema on transmit and receive, you will not be able to easily use the repeater. The Midland is missing a small number of PL tones. If a repeater requires one of those tones, you will not be able to access it.Again, I suggest you search the forum for reports and to determine if these issues are significant for your planned usage. And, note also, the built-in search feature tends to miss things. I'd suggest doing a google search for something like: site:forums.mygmrs.com midland review repeater

I would second that suggestion, Lithium battery. Specifically I would recommend a LiFePO4, LFP, battery. They have the safest chemistry out of the common Lithium battery types, light and reasonably high energy density. One other advantage to LFP batteries is the terminal voltage. At full charge they are around 13.3 or so VDC, a very good match to most mobile equipment that expects 13.8 VDC. The battery has a very flat voltage verses discharge curve so when the terminal voltage drops to 12.8 VDC the battery is almost completely discharged, like around 80 to 90 percent of the rated capacity is used. Don't try this with a lead acid battery. I've also found they have a very low self discharge rate. You can charge them up and let them sit for months and the terminal voltage hardly drops. For an Ecom application this would be an advantage. I've wreck enough Gel-Cell lead-acid batteries over the years I won't buy them anymore if the equipment can use the LFP type. Lead acid batteries don't like sitting around unless they have a trickle charger attached and don't let them sit around at less than full change, they will sulfate the plates. Neither of these conditions hurt LFP batteries. As a matter of fact one recommendation for long term storage of LFP batteries is to discharge them to around 50-80 percent of capacity, they can stay that way for months to a year or more this way without damage. While LFP batteries are much more expensive than the common lead acid type once you ruin a few lead acid batteries you'll get sick of replacing them and the cost adds up. I've had good luck with the following company for LFP batteries. https://www.bioennopower.com/collections/12v-series-lifepo4-batteries If you want to use a solar panel to recharge the battery a small MPPT controller designed specifically for LFP batteries is required. I have several from this company. https://sunforgellc.com/genasun/ I have a couple of the GV5 charge controllers, a good match for a 50 watt solar panel. For solar panels I got some from this company. https://www.renogy.com/products/solar-panels/ I have a couple of their 50 watt mono and 1 of their 30 watt mono panels. The build quality is good and they do guarantee them. On solar panels from my experience don't expect to get more than around 70 to 75 percent of the panel rating, which is derived under lab conditions, which you won't get in the field.

Get your Ham license and buy a 7 MHz (40 meter) HF QRP radio, a small 35 ah battery, a folding or rollable solar charger (optional) make a wire antenna you can toss up in the trees. Call Mayday. No one local will hear you, but many people throughout the nation will and you can ask for help. I have had someone give me grief about this in the past, saying it doesn't do any good to talk to someone on the radio who is 3 states away and my response is always the same.... if I'm stranded in the mountains of Virginia, someone in Georgia, Maine or California can call 911 just as easily as someone in a nearby town.

No. Part 90 is not your party line. 90.403(a), (d), and (e) all limit your communications to only the permitted uses in 90.405, and ( will hold the licensee responsible for any violations, regardless of who is transmitting under the Part 90 license. 90.405(a)(2) limits your communications to transmissions directly related and necessary to your Part 90 eligibility. Unnecessary communications clog up the limited frequency pool for other eligible Part 90 licensees; they too are paying for a license, and interfering with their essential communications with your non-essential communications can warrant FCC investigation. 90.427(a) makes it extremely unwise to publish your operating frequency and access codes to the public, as you become responsible for a stranger's operation. 90.433© also makes you responsible for their radios, and 90.443( expects you to have some sort of Part 90 compliance information for each radio used, in addition to records of all maintenance. If you're not in direct control of the radios used on your license, station inspection (which you're making yourself an easy target for) will get messy. If you're claiming eligibility with some purpose you stretched the truth to make, most of your communications won't be necessary and incidental to the operations stated in your eligibility, violating 90.403. If you make up a purpose you have no intention of fulfilling, you're lying on an official form submitted to the federal government and committing a crime; furthermore, you will not be making essential communications as the eligibility does not exist and no essential communications can be made, further violating 90.403. If you're going to get a commercial license because you are performing commercial activities, go right ahead. That does not authorize you to use a Part 90 authorization to do your Part 95 activities. That is what Part 97 is for. I won't condone the recommendation of Part 90 when the stated purpose of operation is in conflict with the FCC rules and better fulfilled by other services.