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And when will you get one? Kidding! I look forward to seeing your video.

I heard a rumor that the biggest GMRS Youtuber has one and will be uploading a video about it in the next week or so...

I have not. Genuine LMR400 is only $1.62 per foot: https://www.dxengineering.com/parts/tmv-lmr-400 400Max from DXEngineering is $1.45/ft.

BTECH has released the new GMRS-RPT50 repeater, a 50-watt GMRS repeater with a built-in duplexer and auto-IDer. Here are some key features: FCC-certified for GMRS FCC ID: 2AGNDGMRSRPT50 50 Watt Output Power 100% Duty Cycle @ 50W Built-in Duplexer Morse Code Auto IDer Wideband / Narrowband Selectable Rack Mountable (hardware included) 13.8V DC or 120V AC power Expansion Ports Firmware Upgradable PC Programmable Free Shipping We carry the repeater in our online shop, and it's available for immediate purchase: https://shop.mygmrs.com/collections/repeaters-and-accessories/products/btech-gmrs-rpt50-50w-gmrs-repeater-with-built-in-auto-id

I would say the Wouxun brand is the better brand of the Cheap Chinese Radio junk.

I think I will pretty much echo what everyone else has been saying. 1. Elevation/line of site is king. see the below chart regarding my own situation. I can hit the repeater with 5 watts at 50 miles, but if it were not for the elevation, there is no way. folks have hit the same repeater with a hand held from this area. 2. Quality coax. I use LMR 400. one end has the pl 259 connector the other has a n type connector into a antenna switch. This is a build your own cable through dx engineering. The shot below shows the antenna connection to the switch. switch can select from gmrs to sdr. 3. SWR, its more important for xmit, but a tuned matching circuit is better than one that is not. Bottom line is you want as much real energy getting to the antenna, or from the antenna during reception. Best of luck, all the information presented here is good stuff.

Yes, SWR is a transmit function, but losing 3 dB is still signal loss, so yes, the length of the cable WILL effect receive!

Here's a video that (overly) dramatizes the differences in SWR and insertion losses for UHF connectors vs. N connectors. However, while the narrator makes it seem pretty dramatic, the actual numbers don't represent noticeable differences in real life. Reflected power isn't truly lost unless you are using lossy cable and the reflected power is converted to heat. However, for a person obsessed with having nearly perfect metrics, the differences might cause a loss of sleep. Finally, a word about adapters. Adapters are convenient, but if you're ordering cable custom made, just get an N male on one end and a PL-259 on the other and make sure they're good connectors, such as M&P.

When the PL-259 and SO-239 connectors were first introduced, they were called UHF connectors, but now UHF runs from 300 MHz to 3000 MHz and the PL259 and SO-239 are not very good connectors for that high of frequency. The losses for almost everything in radio increase at higher frequencies. Some PL259 and SO239 connectors have a lot of insertion loss above 300 MHz. N connectors solve that problem. Unfortunately, almost every manufacturer sold in the US puts SO-239 connectors on their radios. Most manufacturers of UHF antennas make antennas with N connectors as well as SO239. It's a little confusing, but PL259 is the PLug and SO239 is the SOcket. The numbers came from the military. In an ideal world, GMRS radios would have N female connectors on their backplanes. Fortunately, Messi & Paloni (M&P) and probably Times Microwave (as Amphenol) have developed higher frequency SO239 and PL259 connectors that are supposed to be good for frequencies in excess of GMRS. I buy cables with connectors, but I have cut them to custom lengths. But to me this is a hobby and doiing things like this are enjoyable. DXEngineering will make up cables with whatever connectors you want to any length you want. The tools required for the Times Microwave are pretty pricey but you can get by with just a decent crimper and utility knife if you're very careful. M&P can be done with just a soldering iron and wrenches.

Hello and welcome! What is the terrain like between your antenna and the repeater? GMRS is UHF and is mostly line of sight. It can penetrate some amount of vegetation and homes etc but not hills or mountains. Use this Line of Sight mapping tool to check your path: https://www.scadacore.com/tools/rf-path/rf-line-of-sight/ In the pop up graph you can input the height of the antennas for more accuracy. Start there.

I will throw my 2 pennies worth in, I have been around radios for many years. But I am new to GMRS, I debated for a while on what radio to get and I decided to get the Wouxun 1000g+ and I have been super happy with it. I have other radios for 2meter/70cm use as well as HF radios. I just believe that the radio should and would perform best for what it is designed for. The KG1000G+ will receive all the frequencies but only transmits on the GMRS freqs. Just get on the Buytwowayradio site and list to be notified when in stock, but check everyday. That is what I did and grabbed mine as soon as I saw it available. It is a great radio, I don't think you can go wrong with it.

It looks like their shipping estimate is six days from now. The KG-1000 plus is a good radio and if you’re sold on it I would get on the wait list. It will go by fast. I’m not sure about the radios you are comparing it to but the 1000 is a super het and liked by many. Just my opinion.

I think what they mean to say is the current could flow through the radio during a high current event with some failure point. If say your negative ground from your starter were to break or corrode badly enough (which is common in older vehicles) , the the current or part of it *could* find it's way through your radio through the negative lead

I’ve ran into a few. Fortunately just a small number. Most are paranoid about getting ANY negative feedback. I’ve gotten refunds from sellers that said in their ads “NO RETURNS”. In general my experience has been pretty good.

My repeater station has a female "N" connector for the transmitter and a female BNC for the receiver. As for my mobiles, all of my XTL5000 XTL2500 radios have a female mini UHF connector and my Midland MXT500 and Kenwood TK880 radios have a SO239 connectors. No CCRs for me.

As @kidphc mentioned this is an example of what a "read" of a radio can show you. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/?context=new

I only know of one radio that comes with an N connector as its output. Using adapters is common and they don't really add to any loss figures so an N female to PL259 or N male to SO239 adapters are fairly common. They are a little on the pricey side compared to the normal PL/SO adapters but I believe that is due to the number of connectors sold rather than the manufacturing costs.

I'll give my take on it from an RF antenna engineer perspective... In a few cases that I've seen the coil serves to make what should have been a longer antenna shorter. The classic example is a helical on a handheld, say for the 2m ham band, that should have been 1/4 wave, ie about 19 inches. The coil'ed up whip turned into a "rubber ducky" is electrically 1/4 wavelength long courtesy of the "mutual inductance" of the adjacent winds of the coil. Such an antenna is not 50 ohms but can be close-enough if the diameter/coil pitch and over all length are tweaked a bit. (did you know that a straight 1/4 wave whip is not really 50 ohms either, we shorten it a bit to bring it closer to 50 ohms). As for a coil in the center or there's abouts, of the mobile antenna: That can be to shorten it similar to the above. But most likely it's to give the proper phase relationship (read RF time delay) between the upper and lower straight parts of the whip. This is actually rather simple to think about if one comes to a curious understanding of how antennas work. Let me give that a short try.... The above diagram was pasted in from the web. The red line shows the magnitude (distance from the black line) and phase (which side of the black line) the RF current is on the various wire lengths (in fractions of 1 wavelength). Note that the top end is always zero magnitude. Has to be, at the end of the wire there is no where for the RF current to go, so one can literally start at the top of the whip at zero current and draw the above curves from the top down. Let's look at the 1/2 wave example. If I could place two of these antennas, one on top of the other, then view this from a long ways away at the horizon to the side (where we want the radiation to go), we would see two RF current sources with the same phase and magnitude adding up in my desired direction. We call this "gain". ...gain being more signal in that direction compared to a dipole. But look at the 3/4 wave example above and note that the bottom 1/4 wave has the phase opposite of the top 1/2 wave (assume that the bottom extends below the horizontal line). Such an antenna does NOT have these two RF current sources adding towards the horizon because they are out of phase with each other. What to do??? The answer is simple: put a phase delay in between the bottom and top 1/2 wave sections so that they are in phase with each other. What could that be??? a coil would do this just fine. It would be good to make this coil physically rather small so that it does not radiate well itself, and of course would have to have enough inductance to perform a 180 degree phase shift in order to bring the top and bottom antenna halfs back to "in phase". This is just one example, but should give you the understanding that it is possible to implement this in a variety of ways with different lengths of top and bottom parts, each requiring different coils. Two 1/2 waves "co-linear" is classic and works well. But the coil has to be 180 degree phase shift and that's a lot of coil. More commonly they use say 5/8 wave over 1/4 wave which requires a smaller more practical coil, but does then suffer some undesired upwards radiation due to that annoying extra 1/8 wave part of the 5/8 wave section. Now we enter the world of compromises. Mobile antennas are full of compromises it turns out. The best antennas are the co-linear base station antennas that are housed within a protective casing (usually a fiberglass pipe) where they can implement the above idea of stacked 1/2 wave sections several times over and the fiberglass pipe supplies the mechanical strength. Some of those can reach 6dB and more in gain towards the horizon, something a mobile antenna can only dream of. I sure hope that makes sense and helps.

Here’s what another vendor says: Wouxun KG-1000G Plus Features 30 GMRS Channels 8 Built-In GMRS Repeater Channels 999 Custom Memory Channels 50-53.995 MHz Receive Only Frequencies (6m) 108-179.995 MHz Receive Only VHF Frequencies 320-349.995 MHz Receive Only Frequencies 400-479.995 MHz Receive Only UHF Frequencies (70cm) 700-985 MHz Receive Only Frequencies AM 108-136MHz (RX) Built-in NOAA Weather Channels https://www.buytwowayradios.com/wouxun-kg-1000g-plus.html

Where did you get that reference? https://www.wouxun.com/radios/KG-1000G-PLUS.aspx Wouxun doen't show that on their site. (Not saying I don't believe you... just emphasizing my hardship with finding the right radio given different info on different sites.) I figure if I need to transmit on other frequencies, I can use my UV-5R. Education is the other reason... maybe once I get more comfortable and have folks to talk to outside of GMRS, I'll put more towards communicating on it. You may not care... but if it saved money and works great... would you mind sharing what you use? $2.00 now. You have to adjust for inflation. I appreciate your input and I took your suggestion (added myself to their notification list).

I am using the Compactenna scan-III . Its more of a "general" purpose wide band antenna, but seems to work very well for gmrs. Below are swr results in the 462-467 range, with this same antenna I can get into 2 meters with a swr of around 2 (not great but workable). I think are are other antennas not so "general purpose". Some can more focused on 2 to 3 bands (2 meter/70 cm/gmrs etc)... The third is 420-470 swr results. Its all a tradeoff. best of luck

You should be happy with the M&P coax, which actually has a bit less loss than LMR400 but is not as widely known (yet!) Comet antennas are pretty well regarded, so the station should perform well. Curious to learn the final results in a few weeks.

So after a bit of a rabbit hole on the LMR400 vs M&P, I landed on the M&P Airborne 10. Between that & the Comet, I think I'm on the right path. All good stuff. Appreciate everyone's feedback. I'll report back in a couple weeks once it's all in place. Thanks all.

Thanks Steve, yes there's not a huge cost difference, and I probably won't roll the dice on the cheapest coax. Some budget coax is definitely budget for a reason. I make do with my RG-8X when I need to set up a temporary base antenna. Obviously not ideal.

Have been using SDR's for a long while now, as well as software defined military radios. Wat made me break into the amateur side was finding out that Icom was supplying the first few "black box" receivers for the Predator (RQ-1, surveillance only, no Hellfire missiles back then) fleet. The civilian versions of the PCR-1000 had some issues, like being able to be opened up like those purchased for military/export use. Now, like others have mentioned, I monitor my own networks with SDR receivers, and the HackRF is better than the cheaper USB versions, but it is so easy to just carry along a small USB/antenna and listen to what is nearby. For portability, I used a re-purposed Hinge Health Amazon Fire tablet and SDR# with USB dongle. For the money, great combination and makes the tablet useful again. My newest "scanner" would be a Uniden BCT-15X (possibly a handheld Uniden floating around somewhere), as the SDR USB sticks are on every older computer now, doing something at some point.

The coordination thing is pretty big. The same Line A & Line C that cause issues with GMRS cause more issues with business band licensing. This should be discussed with the coordinator. If you have to coordinate with Canada, that can take months to clear, and if there is a conflict, you pay for coordination again. If you want to go down this path, I would recommend reading all of eCFR Part 90 top to bottom, then read it again in 2 days after you had time to process it the first time. The number one thing you will hear from your consultants is to not buy the equipment BEFORE you get licensed, and I agree with that. Lastly, there are fees you pay to the coordinator, then there are fees paid to the FCC. If I remember correctly, initial filing was $205, and a major modification is $105. Also don't be surprised if your license pops up with conditions of approval noted. It's not necessarily hard, but time consuming, and the actual application on the FCC website is not well designed.

It has something to do with current finding another path to flow via the antenna or it's shielding during high current events, like starting, or winching. They say if wiring radio direct to battery, use fuses on both. If your negative lead is grounded to the chassis, you don';t need a fuse on the negative. I'd have to read more about it to figure out exactly what the scenarios are and why.

I learned that lesson years ago buying sockets. After my second trip get a new socket, the light went on.

Laird 4605 and LMR400 from Times Microwave....I'd rather spend the funds now vs speniding money over and over for the same thing.

If you buy from Kemp, or any reputable dealer, you tell them what you want and they will sell it to you OR, they'll tell you what they have on-hand .. if you buy from ebay, beware, its a den of thieves and liars.

So at 450 MHz RG213 loses 5.2 dB in 100 feet, so in 60 feet you’re losing a little more than 3.12 dB. That’s half of your power. That also affects your measurement of SWR if you’re measuring right at the radio because you truly are not measuring the power that reaches the antenna and the reflected power measurement is much lower than it truly is. Try temporarily shortening your cable and measure the SWR right at the antenna.

I'd bet half the traffic you hear in any large metropolitan area is not even licensed. Particularly in the Las Angeles basin area. And i would even stretch that to include actual repeaters. I'm even hearing a lot of business using GMRS now, like Motels, Grocery Outlets, Construction Co, Landscaping Companies.. I've had a few landscaping companies try to use my repeater, they are hard to get rid of, they don't care. But when you learn who they are and get in touch with their owner and educate them on the FCC laws they will disappear. Self Policing the GMRS repeater Bands and getting harder and harder, sometimes i just turn it off. Thank goodness for the remote access.

New to GMRS and found this conversation. I live in Kiln Creek and am trying to learn about repeaters…not terribly difficult in concept but haven’t had much luck - perhaps too early in the day for most folk . Wish you all well and perhaps we’ll get to chat in the future!

With the current firmware and v2.02 of the Radioddity CPS software, Channels 31-54 should be DIY.

Another vote for the KB9VBR J-Pole. Best $30 i ever spent. Not everything "cheap" is junk. I bet this antenna would easily outperform some $150+ antennas on the market.

im using KB9 VBR J pole antennas https://www.jpole-antenna.com i have 3 of them running two vhf and one gmrs and they are flawless best swr and all 3 paired with lmr400 cable on a i had a fiberglass antenna before and it lasted 6 months before lightning took it

With the latest Radioddity GM-30 firmware and version 2.02 of Radioddity’s CPS software, Channels 31-54 become DIY! oh rtfM… never mind!

The Hustler G6-450-3 is a stout, long life antenna.

My OTHER theory is that the corkscrew just allows you to have a shorter antenna with the same electrical length, and it has nothing to do with performance, other than having a shorter antenna that is just as performant as a longer one.

I've always assumed that the corkscrew makes the RF electricities spin-around faster and then squirt out of the antenna at a higher rate, making them go more fars.. ..i could be wrong though.

I bought one of these about 9 months ago to use with my repeater built from 2 Wouxun KG-1000G 50W radios and a Fumei mobile 50W notch duplexer. I initially used it to replace a TRAM 1486-B with 6.5dBd gain; the Comet has 6.85dBd gain. The installation was at 45 feet above ground and the results were marginally better. I could only get around 5 miles range with either antenna. I live a swamp in southeastern Louisiana so there are many 80+ foot trees over flat ground. I used an EZ-Hang slingshot to place a rope 75 feet above ground. Didn't get much of an improvement in range and I had to use 126 feet of KMR-400 coax. I measured 62% insertion loss through the coax. I bought a professional spectrum analyzer and tuned a used Phelps-Dodge 6 cavity BP/BR duplexer I found on eBay. I detected another slight improvement. What seemed give me a more solid range was inserting a NooElec ultra low noise amplifier between the receiving radio and the duplexer. Suddenly, I had a fairly solid range at 7.5 miles radius, and 19 miles while driving on top of overpasses. i conducted range testing with a 20W (that transmits 16W) Btech 20V mobile radio. I also used a Surecom simplex repeater with an HT to parrot the full duplex repeaters output because I was testing by myself while driving around. Anyway, after 2 weeks of excellent repeater coverage, a rainstorm cause the two halves of the Comet CA-712EFC radome to separate. The top half of the radome is now permanently 75 feet up in the tree! Realize that I have a rope tied to the top of the antennas that hang off a branch. I replaced the Comet antenna with the TRAM again. Under the same conditions, the range is about the same, but not with solid coverage. I will probably buy another Comet CA-712EFC and pull it up the same tree, but before I do so I will epoxy the two halves of the radome together. The compression connection between radome halves isn't designed or strong enough to mount the antenna from the top with all that coax hanging below. I do recommend this antenna. It works well, but I wish there was a way to tune it. It is made with a collinear coax design. Mine came center tuned at 465mHz, but the VSWR on the input frequency of 467.55mHz was about 1.5:1 VSWR and higher than the output frequency of 462.55mHz at 1.3:1 VSWR. I would prefer better tuning on the input because if the repeater is deaf, it will also be mute.

I've played around with SDR using a RTL2832U dongle that I got from the Hak5 shop years ago and Gqrx on my Linux Box. I think my main drawback is not having a very good antenna. Other than that they are a lot of fun to play around with. In fact, pulling out the SDR and trying to listen to stuff got me thinking about Amateur Radio which lead to GMRS a couple weeks ago and here I am now, LOL.

I rarely hear much when driving during the day. I do hear the brunswick and lakewood repeaters identify on schedule, but never heard another user. My repeater is down due to a broken antenna, but never reaches that far either. We really only use GMRS for family events and trips, being we can often be out of cell phone coverage, and its a ton easier to hit PTT and get their attention rather than pull the phone out and attempt a call. I know some neighborhood groups use GMRS to keep track of each other, especially during long power outages.

Our radio club installed a repeater in Marathon, Florida in the Keys. We considered a whole laundry list of antennas in our search for a high performing antenna that would be easy to maintain and simple to take down when a hurricane approaches. The Comet CA-712EFC fit the bill and got the nod. We're happy enough with it that we've purchase two more for the next two repeaters we'll put on-line. I went ahead and purchased one for my home QTH, where the Comet far outperforms my old Laird CRX 450 and the 11 dbi gain Yagi I previously used.

Bob was one of my heros. RIP

Use DSD plus fastlane with your dongle for the best public service you can get, 35 Bucks for lifetime and it handles simulcast better than any of my scanners. 10 Bucks for a year if you want to try it.

Have a dozen of them. Monitor multiple P25 trunked systems with mine as well as ADSB Recevier and APRS IGate. I prefer Airspy but the cheap ones on amazon seem to work well for APRS and ADS. I use quality antenna systems on all of them and not the packages stuff that comes. On my APRS I actually run a pass filter to keep the other VHF stuff at home out of the receiver.

I don't know how it works in Canada but my basic understand of US law goes along the lines of "If it isn't expressly forbidden, it is allowed".

I have been building a portable repeater based on the Retevis RT-97. I was using a 5/8 until I received my Comet CA-712EFC. While it didn't extend my range appreciably, it did provide a very nice S/N improvement and helped fill in some 'holes' in coverage. My son lives 5 miles away in an apartment building with a lot of metal siding. He was able to find some spots in the apartment where his 4 watt handheld could hit the repeater reliably, but at best the signal was barely tolerable, lots of annoying fade. With the Comet, he can talk from most spots in his apartment and sounds 'good', not great, but certainly a whole lot better with little fading (he still tends to forget to hold the antenna vertical). While not in the professional, commercial, industrial duty antenna category, I would certainly rate it in the 'Prosumer' category. Easy to assemble and mount, with shrouded N connector, only a little more weight, and about the same wind load as my 5/8. My old antenna exhibited a 1.4:1 SWR attached to the RT-97. While the Comet is advertised as being 1.5 or less, when I tested it I could not see the return loss needle on my meter budge... so I rate it as 1.1 or less for my particular antenna (within my eyeball resolution of an analog SWR meter). So all in all I am currently very pleased. We'll see how it ages.

I use the antenna. Currently installed at 40+ feet. LMR400 into the radio shack, then adapter cable to radio. Excellent SWR at the antenna and in shack. No complaints. Michael WRHS965 KE8PLM