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Those SWR numbers are not accurate. Keep in mind that SWR is calculated by the following formula: SWR = (Forward Power + Reflected Power) / (Forward Power - Reflected Power) But that requires an accurate measurement of the percentage of the reflected power compared to the original power output. At GMRS frequencies RG-8x converts 44% of the RF output to useless heat before it ever reaches the antenna. So of the maximum of 50 watts transmitted by a GMRS radio only 27 watts reaches the antenna. That’s the Forward Power. Then, if the impedance of the antenna isn’t perfect, some amount of the power is reflected back towards the radio. That’s the Reflected Power. By the time it reaches the radio 44% of the reflected power has been converted to heat. So, let’s say you have an SWR meter right at the radio and let’s also assume that the antenna truly has an SWR of 10.0:2 at 462 MHz. An SWR of 10.0:1 means 67% of the forward power is reflected. That’s a pretty abysmal SWR for any antenna. So for a 50 watt transmitter 33 watts reflects off the feed point of the antenna and back towards the radio. But now let’s introduce attenuation. 50 watts doesn’t really reach the antenna. We’re using RG-8x so only 27 watts reaches the antenna. Two-thirds reflects back towards the radio, so only 9 watts of power is radiated instantly. 18 watts is the reflected power at the feed point but of course 44% of that becomes heat due to attenuation. 56% of 18 watts, or 10.1 watts makes it back to the SWR meter. So the SWR meter sees all 50 watts forward power and only 10.1 watts reflected power. It’s calculation says that is a perceived SWR of about 2.6:1. The point is that lossy coax results incorrect SWR measurements, whether done by a nanoVNA, an expensive bench model Vector Network Analyzer, or the priciest antenna analyzer out there and seeing a lower SWR becomes meaningless.

I don’t recall ever saying that you are using the wrong coax. I pointed out that RG8x has a foam dielectric and RG58 has a solid dielectric and that’s why RG58 is frequently used for mobile installations. RG400 also has a solid dielectric and a tiny outside diameter. It’s expensive though. A person could build a Frankenstein cable using RG400 where needed and something with less attenuation elsewhere to make up the necessary length, but the splice points reduce reliability and potentially add losses. Also, nothing I’ve said has been demeaning or critical of you or in any way personal. I’ve tried to stick to factual information, demonstrating how I did any calculations.

I’ve been meaning to grab some for a long time now. I think you’ve got me motivated to pull the trigger finally.

Im just trying to help and little, but i think there is benefit to watching this video. I put it together for some new Hams in my club, but the Amateur frequencies in UHF are close enough to GMRS, that the demo is still very valid.

No, you illiterate. I specifically stated that it's an NGP antenna. But even an NGP antenna can often benefit from a good ground plane.

The Signal sticks come with male and female SMA connectors as well as BNC. I use the signal stick on all my HTs.

The spec sheet for the RG400 cable shows a loss of 28.3 dB at 400MHz per 100 meters. RG8X has a 26.25 dB loss per 100 meters at 400 MHz.

Antennas typically consist of reactive elements and radiating elements. The reactive elements are used to match the impedance of the radio and feedline which is usually 50 ohms. The radiating element is one or more metal wires or rods that convert the signal into RF. It’s usually the most visible part of the antenna.

How do we "loose" an attitude? And which one is it? Should we stop discussing this stuff or should we share our knowledge and experience? I'm confused.

So what is the right cable? "You're doing it wrong" isn't helpful information. It might make you feel superior, but it sure as hell isn't going to save me any heartache or money.

Welcome! I think my first experience with FRS was road tripping, too.

I understand that some repeater owners want to know who is using their repeater even though they list it as open and therefore the request permission option is set. It’s their repeater so I guess it’s their prerogative. I do personally feel if it’s open then turn requests off. Less to deal with for the owner for sure. I guess it depends on how people behave in a given area. One thing I think for repeater owners that is not a great choice is listing a repeater as permission required, keeping the tones hidden and then using 141.3 as your tones. Many consider this to be a travel tone and may not be a great choice for a permission required repeater if the owner is trying to make it obvious it has restricted use. Just my two cents.

I recently installed some NMO mounting points on my truck, but for a variety of reasons, I wasn't entirely satisfied with them and decided to do it over. For the first installation, I used generic Chinese RG8X coax, but this time I went with USA-made MPD digital RG8X. The first thing I noticed was that the MPD coax is much more flexible and easier to work with, but even more significant is what happened to my SWRs/Smith graphs. With the Chinese coax feeding a Diamond SG7900 Super Gainer NGP 2m/70cm dual-band antenna, the 2 meter and 70 centimeter bands were good, GMRS was in the "I can tolerate it if I don't use it too often" range and MURS (Which I've never used and could live without, but why not test it?) Started at 2.0:1 and went up from there. The first four pics are the sweeps of GMRS, 2m, 70cm, and MURS in that order with the Chinese coax and the last four are the same after changing to the MPD coax on the same antenna. 2m and 70cm remained good and even improved a little, but GMRS and MURS improved dramatically -- all the way to, "Yeah, that'll do." If (like me) you have sometimes wondered, "Does it really make that much difference?" the answer is yes, it does. The MPD ain't cheap at $2.34/foot, but I only needed 30 feet. TBH, even if I needed 100 ft, I'd buy the MPD. The difference is that obvious. As the saying goes, if you buy the best, you only cry once.

Hey, just trying to spread some love. I know some people here might not seem like they love each other, but think of it this way, it can be just as difficult picking the right coax. No shame in selecting the wrong coax, just admitting to yourself you made a poor choice is the first step towards inner peace.

I ran the numbers using the https://kv5r.com/ham-radio/coax-loss-calculator/ for several types of coax. Here are some screen shots showing the losses for 100ft of coax. LMR400 RG-8X RG-8 1/2" Heliax

You Just Posted It..... Another Attitude - Please Re-read My Post - Or Not...... Peace Out.....

Hello All, We now have 22 members who have joined the South Central Tennessee GMRS club since its inception on October 26 of this year. I started the club when several contacts commented that a club would be nice so I volunteered to set up the club on myGMRS.com, however, I only wish to be involved with moderating the site. I am sure there are already members here that have much more experience with clubs of this type that can provide valuable input towards what types of activities other members would find interesting and helpful. Also, I encourage you to post (if you have not done so already) on the New Member Info page some information about yourself, interests, repeaters you monitor, etc. so we can start connecting names to the callsigns. Again, thanks for joining and promoting the club to other GMRS users, Steve WSBM 443

Went to get one the other day, Can't order now till June.

You simply use the correct cable, and RG8x is simply not going to cut it on UHF. Only place RG8x should be used as a compromise cable at 30MHz and below, and that's a stretch. You lost so much power using the stuff it even fooled you into thinking you have an acceptable VSWR, kinda like a dummy load. Just trying to save you heartache and money.

I've tried the Nagoya 701G and 771G on my KG-935G and the stock Wouxun antenna performs better. I do see an improvement when using the 771G on my Baofeng UV-5R GMRS radios.

Thank you for the reply I also have a baofeng but it's a uv5G plus and two TD H3's . I'm addicted to these little radios.

Put the SWR meter at the end of the run of cable and before the antenna if possible and you will get a more true reading of the antenna SWR. Coax can introduce as SWR as well so it'll still be higher than what the near antenna reading is.

I've been thinking of turning access request off on mine.. My repeater is open with no tones. It's there for anyone to use as advertised. Of course, rules apply. Only had one problem early on when a local guy insisted on belching every other day on the repeater, until i actually busted him doing it as he was sitting in his mini van in a nearby grocery store parking lot. Kind of funny when you roll up on someone and you nail em .. Never had a problem since. Nuff said.

One friend is using a rugged radio G4, and the other is using a Radioddity GM-30 handheld. I will have them check if they are set to wideband, and also I will try holding the mic at different positions. Thanks for the help.

If The Repeater Owner Has Previous Approved Or Denied Requests Attached To Their myGMRS Repeater Log, The "Request Access Disabled" Function Is No Longer An Option, Regardless Whether The Station Is Listed As Open - With Or Without The Squelch Tones. The Only Way To Correct & Have That Option Available, Is To Delete The Listing, Which Deletes Previous Requests, & Re-post The Repeater Station. Some Repeater Operators In WI Done That When They Went From A Paid To An Open Repeater Station.

It is certainly interesting when you chart it that way. As you say, the SWR improved on the bands for which the antenna was not designed, but not on the bands for which it was designed. In effect, it made this antenna a little more broad-banded. Now I need to do some more testing. I'll try a couple of different antennas and maybe the dummy load test.

He's using a nanovna -- it has the smith chart on it.

That does make a difference, but what is the actual difference? How much of the difference is due to the antenna? Are the cables exactly the same length? Have you tested the insertion loss for each cable at each tested frequency? Remember, attenuation in an antenna makes SWR appear better. I believe these are the tabular results and I’ve arranged them by frequency It appears the older cable actually results in lower SWR for the 2 meter and 70 cm bands when connected to an antenna designed for those frequencies according to the value in the upper left of the screen. It would be interesting to see a single wideband sweep of just the cables into a dummy load to eliminate the effects of the antenna. Frequency Old Cable SWR -> New Cable SWR 462.000-470.000. SWR 1.900:1 -> 1.495:1 441.000-450.000. SWR 1.464:1 -> 1.498:1 151.800-154.600. SWR 1.888:1 -> 1.408:1 144.500-146.400. SWR 1.151:1 -> 1.395:1

Would anyone here be interested in setting up a trivia game bi-weekly or monthly? A different person would volunteer to create the questions and keep give answers at the end of each round. Maybe 2 or three rounds of 10 questions. Scoring would be on the honor system. No prizes, just for fun and bragging rights.

IME, the general rule is that assuming both antennas are appropriate to the band I want to use, I'll get a bit more distance and clarity both rx and tx with the longer antenna. Often it isn't enough to matter, buy sometimes it's pretty noticeable. Individual radios may sometimes prefer one antenna over another for reasons I don't understand. That's kind of a long way around to say try them both under the same conditions and see what you get.

I am sorry you are having reading difficulties. But thank you for letting us know!

Hello everyone! New to GMRS -- My sister gifted me a Midland MXT275 with the 3dB ghost antenna, as well as the 6dB whip which is still on the way. It was super easy to install and has been fun to use on the FRS channels when we road trip with friends! I haven't talked to anyone on the GMRS freq's yet, I've only made a couple calls into the abyss asking for a radio check. Still learning, and hoping the MXT275 will last me a while! Located in Eastern, WA - Zack

There’s a very high probability that he has everything unlisted because he doesn’t want to allow anyone else on it. That’s his prerogative. Stalking him probably won’t make him more amenable to allowing you to use it.

This means it’s an open repeater and no request is required. Follow any rules they have and enjoy.

Seriously, why not? They are not that much different to install than PL-259. In fact with these M&P connectors you don’t even need solder:

It's a trade-off between cost, ease of installation, performance during operation, and a bit of everyone's different opinions thrown in. At work, I ran two 200-foot runs of Times Microwave LMR600 between the roof and our basement office. One was for a cellular repeater antenna (this pre-dated the pre-registration requirement, by the way) and the other was for a GPS antenna. I had to put a 10dB attenuator between the indoor lightning arrestor and the Wilson cellular amplifier or I'd overload its front end. The General Dynamics box the GPS antenna went into was perfectly happy with the GPS signal level. All the connectors were ordered from Pasternack, as were the LMR600 stripper and crimper. I have a leftover piece of LMR600 with an N connector on the end that I use as a walking stick. OTOH, my entire (large) collection of home-use connector adapters cost less than two of the Pasternack LMR600 connectors. It's a trade-off between price, performance, and personal opinion. My repeater is currently using some no-name super-flex 400 (they can't call it LMR because that's a trademark of Times Microwave) to its temporary antenna. If the Commscope / Andrew fiasco ever starts producing antennas again, my DB420-B will be connected to the entry point lightning arrestor using 7/8" heliax with N connectors. My grounding consists of eight 8' long copper-clad steel grounding rods, 16' apart, with one end tied to the electrical service ground. The whole run from service ground to the antenna lightning arrestor is one continuous piece of #4 stranded copper with green insulation jacket except where the jacket was shaved to connect to the grounding post clamps, electrical ground, and lightning arrestor ground terminal. Forgive the non-GMRS pictures, but they do show good (to me, at least) cable installation practices... You can't see the outdoor lightning arrestors as they're at the point where the cables are about to go through the roof penetration.

I just got my RepeaterID for the RT97L and they even emailed me the file I sent them for the announcement for free. https://www.repeaterid.com/store/p16/RepeaterID_RT97L.html# I got it in 3 days and very easy to use. It works great!

At least it's not water infected like mine got. I went from a 1.15 to a 2.08 and reception and transmission were affected substantially. Under 26ºF everything went good. As soon as it went over freezing it went bad. After the cold weather went away so did my reception and transmission. Replaced the bad antenna and coax section got swapped over to Heliax. Great stuff. Good luck with solving your issue. It's never fun when it happens and you can't figure out why.

I leave mine on all day and only have a 2 mile trip to and from work. The draw for receiving is pretty small and more so if you have your lighting on the radio extinguish after 30 seconds after activity. When it's the dead of winter and temps are way below freezing I'm more mindful of the battery. But in the warm periods I don't think twice about it.

@DeuceoneRadio great job on the research. I guess I have a little different philosophy on continuous power to the radio. I don't do it much, but sometimes I reach in the truck and turn on the radio briefly. I don't feel like pulling the keys out just for that. Maybe I'm just lazy.

I'm sure that you can get at least a couple of people from the local amateur radio club to help. Most enjoy helping especially when it comes to putting antennas up. And if they do help and try talking you into getting our amateur license, you can always tell them that you want to get your feet wet first with GMRS. We have a couple of members that struggle to get their amateur license due to health issues. We haven't pushed them into it and have suggested they start with GMRS. They have all taken our advice and are on the air and using the GMRS repeater.

Hello everyone and thank you for taking the time to read this question and answer it. I do realize that this may be a heavily asked question; however, I am hoping to make the answer more efficient and richer in data so others who find themselves to a similar position may have answers or at least a direction to go in. I am relatively new to the GMRS world and even newer to the repeater side of things so my knowledge is severely limited, at best. Using the forum here to gather information on the topic I found that a simple basic repeater system is composed of the following: 1. Dual-use or Omni antenna for transmitting (TX) and receiving (RX) signals. 2. Feedline or Hardline to connect the antenna to the duplexer. 3. Duplexer 4. Receiver 5. Repeater 6. Transmitter For a visual representation of this system, a great visual will be used from www.repeater-builder.com listed as figure 1. Now that the basic premise of a repeater has been shared, along with my depth of knowledge on the subject, let me pose my question to the greater community: Looking at each of the six enumerated items above, what is a business that sells them (please include a link to their page) and what is the closest you can get to plug-and-play type of system (what model)? Ideally, in as simply a way as possible, how does one build a repeater from scratch without having to endlessly search Ebay or other sites for old transmitters/receivers. I would like to purchase new, with the ability to change my broadcasting power (not be stuck with 10w pre-made systems but rather make a 50w or greater system). Along with having a link to each of the numbered items showing a product and how to connect all of them. Think of this as setting up a computer for your parents who have never seen/used one. Explain here is the printer, it prints things you want and here is a hyperlink to brand X printers. It will use a USB cable to connect to the computer itself and here is a link for each of those. Then so on and so forth. Once all of the information has been gathered and collected, I will repost so it is a simple way to find information and resources to purchase. As of the current time I am looking at how to build the repeater and what it will take to make it work when I flip the switch and not the FCC document submissions…yet. Once the system is built, functioning, and I have made my measurements I then will submit all of the information to the FCC seeking permission to install and “open for business”. Thank you all for your help with this and look forward to all of the information! < Figure 1 courtesy of www.repeater-builder.com