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I finally received my shiny new RT97 portable repeater yesterday. I chose to have them program it in the ham portion of the UHF band, since they don't charge extra for it, nor for tuning the duplexer. I do have the service equipment here in case I ever need to retune the duplexer. So far I'm very pleased with it's performance even though currently it's connected to a tri-band NMO mag mount antenna on a 14' diameter pie pan. I was able to hit the repeater full quieting about 3 miles from my 40 watt mobile. I've read elsewhere that many (including our very own Rich!) have had problems getting the programming software configured properly. After several attempts, I finally discovered that Retevis only allows COM1 through COM20 in their software. On my development computer all COM ports 1 through 22 (save one) are already in use, so the system assigned COM23 to the Prolific programming cable! I noted that COM2 was not already in use, so I had to use the Advance option to re-assign COM23 to COM2. Bingo! Now the darn thing will connect and will allow for read/write operations to take place. I note that the RT97 has 16 channels that may be programmed. Evidently the duplexer they are using will allow +/- 500kHz to pass through adequate signal, so they have pre-programmed the other 15 channels accordingly! This has proved to be a blessing since my primary channel (#1) is 442.975/447.975. The closest repeater on that pair is in Attica, Indiana, nearly 120 air miles from me so I thought that was clearly enough separation to cause no problems, especially since I chose to use 141.3 CTCSS for the input/output tone. Unfortunately, Attica is a DMR repeater and the analog 'machine gun sound' has been coming in loud and clear! So I've moved up 12.5kHz (channel #2) to eliminate the nasty sound... I am intending this portable repeater to be used primarily as part of our ARES group here in NW Indiana, and am anxious to get this outdoors for some range testing!

Fair bit of questions here. Tuning is done through the KPG software for the radio, HOWEVER, I would not attempt to retune a radio without the proper meters and equipment and a surecom 102 isn't the best to meter for perfection. One thing I do question is, have you tested the meter against a known source? I do use a surecom meter myself for quick checks, and I recall that I had to tune the meter before I could use it. It took a few trys however I did get it to be close enough for what I do. IF you choose to do this yourself with cheap equipment, I am not to be responsible for damage or rule violations. You will need a length of coax about 1.5 times the frequency wavelength, (9 or 18 inches should work) the meter, a 50 ohm 100W dummy load able to support the frequency you are tuning for, radio, power supply, programming cable and computer with KPG49D software. Set up the radio and power supply, connect the coax from the radios antenna port to the "Input" side of the meter, and connect the dummy load to the "Output" side. Connect the programming cable, and turn the radio and computer on. Open the 49D software and do a read from the radio. Click "Edit>Test frequency" Enter in several frequency sets, You should have the lowest frequency you plan to transmit on, the highest frequency, and a frequency somewhere close to middle between your high and low frequencys. Save the file, and write to the radio. Once written, click "Program>Test Mode" Select the center frequency (likely to give you the best results for your usage "band") Double click "RF High Power" Take a note of the current value, Just in case you make a mistake, you're able to return to this number and start again. Use the left and right arrow to adjust the value in the new window. Make small adjustments and click "TX" Get a reading and click "TX" again to stop transmitting. Keep making adjustments until you reach about 40W (This unit is rated at 40W output to my knowledge) You can run slightly low, however to protect the radio, I wouldn't tune above 40W. Once complete click "OK" to exit to the test mode window. Select the lower frequency and go back into RF High Power, DO NOT MAKE CHANGES, Simple click TX and take a reading, and do the same for the High frequency. Note, Both frequencies will be BELOW the 40W output. This is NORMAL as long as they aren't super low. When complete, click "Close" in the test mode window, and your radio should reboot. For low power, I don't believe that radio can go much further than 20W low power without causing damage to the radio, and for frequency alignment and getting into the 70CM band you would likely do better taking the radio to a shop and having a pro do it for $50. This will void the part 95 certification, however at least there is less risk of transmitting way off frequency by accident. I would also advise against any physical adjustments on the radios boards as a 1/4 turn on the wrong pot will fry your radio, your station, or worse, could cause a fire. Again, most shops can preform this service at a reasonable price for you.

Looking for the mix of both the lowest Smith (impedance) and SWR, but you can always improve the match if you get good swr by adding a capacitor to bridge the antenna and ground (shield).

Here is a snap shot of my NanoVNA showing the resonance of the external GMRS at my home. The resonance can recognized by the sharp dip in the yellow LogMag trace. Since the impedance of the antenna (as depicted in the green smith chart) is also closely matched to the 50-ohm coax there is also a corresponding dip in the SWR. So this image shows that, in my case, the best SWR reading corresponds with the resonance of antenna. So, in part, how can you view the resonance of an antenna independent of SWR? Use a NanoVNA, perform an S11 measurement with the instrument set to display the LogMag trace. Hope this helps. . Michael WRHS965 KE8PLM

If you are using the repeater memory slot. Which should be memory 15-22. Then no worries with the frequencies it should automatically listen to 462.xxx and transmitting on input 467.xxx. Make sure it is the right frequency. As far as your DCS codes that sound about right. Program it and clunk away to see if you break the repeater's squelch.

I drive an 01 Silverado and here is my setup. For daily use locally I carry a Wouxon KF 805G, attached to a roof mounted antenna and powered by the battery eliminator. When I go in a store or whatever I disconnect the coax, slide off the eliminator, attach the "rubber duck" antenna and slide in the regular battery and off I go. For "road trips" I fashioned a mobile mount out of some plywood and "L" brackets for a mobile CB and mobile GMRS. While driving it sets on the Trans tunnel, If I'm staying in a hotel I disconnect both radios and carry the set up into the hotel room. The KG805G isn't high powered but it works for me locally. The mobile setup isn't pretty, but I'm not in a truck show. Hope this helps and enjoy!

I would also recommend the KG1000G based on what I've seen and read about it. I have one on the way, but haven't received it yet. Like you, I also have the GM-30 (a few of them actually), and recently purchased the UV9G too. The GMRS radios are what I pass out to family members when I want us to be able to communicate. I think this is a great solution for family communications when hiking, camping, bike riding, etc. They may lend themselves to an SHTF situation, as long as there aren't too many others trying to use the same airwaves at the same time. If you get a Baofeng for SHTF scenarios, my recommendation is to get more than one. They provide much more capability than a GMRS radio by virtue of the frequencies on which you can transmit. GMRS is limited to the standardized channels (actually specific designated frequencies), and in many cases you don't have the ability to transmit "out of band," so to speak. With a dual- or tri- band ham radio, you have a lot more frequency space to work with and you're not limited to specific (channelized) frequencies within that space. While it's true that a $25 radio will generallyget you $25 worth of performance, it's functionality will be largely dependent upon the ability to contact someone with it. If there's no one on the other end to talk to, it won't matter how much you paid for the radio. CCRs are great to use for learning purposes, and if you have several of them, you can pass them out to your friends and neighbors in a SHTF situation. As you familiarize yourself with the Baofeng, you will likely also become more interested in getting your ham license, which I would recommend anyway, since it would allow you to transmit with the Baofeng to communicate with others. If you like the GM-30, there is another CCR that has slightly better specs than the Baofeng, and is similarly priced. It looks nearly identical to the GM-30, but comes in a ham radio variety. Take a look at the TYT-UV88 if you're interested. The other nice thing about the CCRs is that as your interest grows (and likely your inventory of better radios), you can use the CCRs as backup radios.

If you do remove an NMO mounted antenna for safety while using the carwash, please do be sure to buy a screwon cap for the NMO mount...

Quick related story: I am 10 months new to GMRS and love it. I didn’t know anybody but have made friends in my area. Got into it first because I retired and so had the time, and because it was so easy. But I also got interested in Ham, and so I studied and about 2 weeks ago I took my Ham technician test and got my ticket. When I was at the testing site, there was a place on the test application form for a current call sign (if you have one, like if you’re going from tech to general or extra). I left it blank. When I handed my form into the VE, he asked me what my call sign was. I said “well, I don’t have one”, and making a dumb joke, I added “unless you want my GMRS call sign” (I was proud to have it). The VE scoffed as if it wasn’t funny at all and said “no”. He probably didn’t really mean anything demeaning, but with voice inflection, the way it sounded to me he did. I hope it was just me imagining things. So I am a Ham now. I pledge to never be one of those "sad-Hams" or knowingly be arrogant. Like I said, GMRS is my first [radio] love (Ham second, CB third…yep, still like CB). : ) ... Edit after thinking about this after posting: To be fair, absolutely everybody on Ham has been extremely nice/cordial to me on the air, so much that I am somewhat taken aback. There is not one exception. I so very much appreciate that, and am truly moved that they welcomed me aboard. So don't think for a minute that most Hams are sad-Hams. That said, I also think it's humorous that on GMRS, the guys and gals kind of "ham-it-up" some, by which I mean trade banter, poking fun, taking jabs, bustin'-chops, whatever you want to call it. Both Ham and GRMS are fun, and that's one of the two reasons I got into them, and I'm glad and proud to be apart of both!

Of course, most replies will be much opinion, so here is mine: 1) IMHO, the Wouxun KG1000G is a great radio - it has a 50W output, but the best feature is being able to throw the chassis under the seat (or wherever) and remotely mount the very small faceplate anywhere. I have also used the BTech GMRS 50X1 - actually 2 of them, but that radio does not output anywhere near the advertised power output and the screen is tiny/hard to read.. but, it is cheaper..sooo... 2) any GMRS antenna is probably "good enough" - on both my Jeeps I use the Browning BR-450 which is a UHF antenna and must be cut/tuned (not a big deal) - but a "GMRS" antenna should not need to be cut/tuned 3) it depends on the antenna & where it's mounted, but to be safe I would remove it. Assuming you mount it where you can reach it, the GMRS/UHF "NMO" mounts are easy screw-off, so its very fast/easy to remove. Tram makes a very small (6 inch?) that works great, and would probably survive the carwash just fine.. 4) There are no designated GMRS channels (technically there, are but, like you, nobody knows about them) and in most areas the airwaves are dead - its not yet like CB as far as activity. 5) I dont have any pics, but, dont overthink it.. Mount the radio where you can see it, and mount the antenna where it works - be warned that experts will tell you that if it's not mounted in the "right" location, "it wont work" - dont belive it. Jeeps are notorious for not having any "good" mounting locations (due to the lack of a metal roof) and both mine are mounted where the experts say "is terrible/wont work" - and yet I can talk to my wife in her Jeep, also with a "terrible" antenna location, 25 miles away, and I can easily hit a repeater 70 miles away while sitting in my garage with the door closed.