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In this case you should at least ground the shield of the coax before it enters the house. This would be a minimum requirement, because your antenna will accumulate static charge just from the wind, no lightning necessary. Give static a path to the ground other than through your radio. Bulkhead N or PL-type connectors can be used at the bottom of your mast or at the entry point into the house. Better solution is to use lightning arrester certified for 500MHz, as mentioned above, and a proper grounding wire and a dedicated grounding rod near the mast, bonded with the house grounding rod by #6 or bigger wire. This method is according to the code. I myself do have rod for the mast, bonded with the house ground by #4 wire, but I only ground the shield of the coax. Where I live, lightnings happen once in 10 years.

1. Make sure you’re using test equipment that’s high quality and accurately calibrated and appropriate for the frequency and power level you’re using. Make sure you’re testing at the specified voltage (13.8!) and using power cables that won’t cause voltage drop. It might help to visit a local radio shop. 2. That can depend on a lot of things. Is your power wiring noisy? How high quality is your coax? When it comes to antennas, everything affects everything and a noisy power cable parallel to the coax could cause problems.

Thank you for your response. When I was measuring, I had the radio connected to the meter and the meter connected to the antenna. The vehicle was turned off using only battery power. My concern was the radio was only putting out half its power, I just want to make sure it is capable of putting out full power, like all the others of the same model I have seen tested. Thanks again for your help.

I am new to the GMRS community and I was wondering why my SWR is higher 1.74 on NON repeater channels and on repeaters it is 1.01?

All masts should be grounded and all fixed location antennas should be connected through a lightning arrester where they pass into the house. A lightning arrester grounds the shield of the coax and also helps protect the radio from static electricity buildup.

I use one of these antennas and in my area, it is the only way I can hit some local repeaters, so it does make a difference. Just keep in mind that it is directional. I can hit some close by repeaters from the back side of the antenna but I can also hit those repeaters from a hand held.

Or just grab a RT97 for half the cost of the KG1000 setup.... KG1000 - $369.00 x 2 Duplexer - $150 (Fumie China Duplexer) Various cable - N-PL259 (Radio to duplexer) - $25-50 Power Supply - $100.... Granted the RT97 is a high power repeater but 99% of the folks that will be putting up a repeater are doing it at home on a garage or house. The RT97 is a all in one box. Just program and turn on. Simplicity for many. And to be honest if you have a great location the repeater will do fine with portables. Just another option.

I've been looking for information on hair pin match considerations. Post the wrong answer on the internet to find the right one!

That tool is called a Yankee Screwdriver or a push screw driver. I have a few stanley/bailey pattern planes, a European style scrub plane and few other ( brace and bit etc). Use em too when I have a mind to.

1. For any given antenna, SWR changes with frequency. A graph of SWR vs. frequency often looks like there’s a sharp dip at the resonant frequency. 2. Where are you measuring the output power? A dummy load will appear to the transmitter like an antenna that has a very low SWR at every frequency. Also, was your Jeep running and putting out 13.8 volts or were you on battery at a voltage of 12+ volts? On battery power the output power will sag slightly. Or it might just have been the radio you received. Many things can affect output power: input power, antenna cable, antenna, ground plane, etc. 3. Pretuned to center channel probably means that it’s tuned to midway between the 462 (used for simplex communications) and 467 MHz (which you transmit to a repeater) frequencies of the band, or about 465 MHz. 4. Tuning the antenna to have a lower SWR might get you more transmitted watts, but honestly a few watts isn’t detectable in actual use. I recommend either leaving the antenna alone or tuning it to the frequency you transmit on most often. A higher frequency means a shorter antenna element, but if you shorten it too much it’s hard to undo.

Don't have pictures, sorry. My portable setup is FT-817ND + Emtech ZM-2 manual tuner + 20ft telescoping fishing pole + about 60ft of wire. It is more a hiking setup, than a car setup. I'm currently building 3500mAh batteries from cheap LiPO chinese cells that will fit into the FT817 battery compartment. Three of these batteries will serve me for a week, easily, without needing for recharge. I'm not really interested in contests, SOTA and such, the setup is mostly to have a reliable comms to base camp, and sooth my thirst for an engineering challenge of having a reliable comms when resources are limited.

Unfortunately, while CHIRP has entries for TID and TIDRADIO, neither offers up the GM-5R as an option. The radio does support (if I read the adverts) available channels so you don't have to customize the core 30 (unless you really want to). Use the programming cable and the company programmer to make things easy. I suggest the first step would be to /download/ the radio configuration and save it as "factory.<whatever>", just so you can restore a fresh situation without having to invoke a front-panel RESET ALL. Save modified configurations under informative names (or by date modified: yyyymmdd so it sorts nicely). Most programmers will present either frequency and none|+|- (though GMRS repeaters are always +) and a shift/offset (5MHz for GMRS) OR may have columns for Rx frequency AND Tx frequency, along with a choice of TONE (send only) or TSQL|CTCSS (radio sends the tone, and expects the repeater to also send the tone -- so radio stays quiet unless the tone is detected). Oh, DTC is also an option for tone. CHIRP with Retevis RA85 setup. {Note: I renamed some of the standard channels with some ancient "recommended usages" -- 462.675/467.675 used to be an FCC decreed emergency/traveller assistance channel. The "Line A" entries are the frequencies that can not be used near the Canadian border [unfortunately, Line A basically comes right down the middle of Michigan, so anything east of, and maybe including, Lansing can not use those channels].} As you can see, CHIRP is one of those with Rx frequency, offset direction, offset shift. Actual Retevis programmer (I had problems with the RA-85 software, they provided a link to the RA-685 software, which is really a dual-band Amateur version, but the software does seem to work -- and also "unlocked" even more channels: the RA-85 is billed as 60 channels -- 30 basic, and 30 available [though Retevis populates all with random tone settings], the RA-685 software goes to 128 channels and in testing, they work on the radio [I put the 16 "channels" of the RT97 repeater, as I configured it, into channels 113-128]. As you can see, this is software that expects Rx and Tx frequencies, Rx/TX tones [QT is CTCSS, DQT is DCS]. (Oh, and that software is nasty -- one can not resize the windows, so unless one runs in full screen mode, buttons and stuff gets cut off.) This gives you two different styles of specifying the same repeaters. Take what you know of your desired repeaters, and use your software to set up something similar.

Mounting an antenna next to another is not recommended (besides the potential of overloading the AM/FM receiver front-end) the parallel antennas will interact and may cause SWR detuning or an inadvertent directionality of the signal. I'd suggest at least a foot of distance, more would be better. On my rust-bucket Liberty, the mag-mount that came with my MXT115 is near the front of the roof (about where the headrests of the seats, centered), a mag-mount CB antenna is about 18" behind that, and two-three feet in front of the AM/FM antenna. The 2m/70cm antenna is a glass-mount on the left (to get it away from curb-side trees when parking) rear side window (best I could do, even though they say not to mount on tinted glass -- have you seen any car that doesn't have rear&side windows tinted in the last decades?). SWR varies by frequency, and depending upon the antenna, the bandwidth for low SWR will also vary (high gain antennas often have narrower bandwidths, being more sensitive to matching frequency). Presuming channel 1 is 462.5625 and your channel 20 is 462.675, channel 6 would be the closest match for comparison -- also try low power on all that you test (for comparison; the meter may have differing sensitivity based on power). How calibrated is the meter; most consumer gear may not read "true". Also, the radio may have a "roll-back" circuit, in which it reduces output power until the reflected power is below some threshold (this is to preserve the output transistors -- if they are pushing out 50W and 5W is coming back in, the transistor is essentially running 55W). Or was your channel 20 actually the repeater mode, in which case it was 467.675MHz. I'm a bit perplexed by your channel numbers. To my knowledge, the Midland mobiles DO NOT INCLUDE CHANNEL 11. In the 2017 FRS/GMRS reorganization, the channels are defined as: 1-7 GMRS interstitials -- 5W ERP FM on 462MHz. Note: interstitials refers to these channels being created /between/ the original GMRS main channels. 8-14 FRS (allowed on GMRS handhelds) 0.5W ERP NFM on 467MHz (467 is repeater input frequencies, which is why the power is so limited) 15-22 GMRS main simplex channels; 50W out FM on 462MHz 23-30 (aka RP15-RP22 or such name variations) GMRS duplex (repeater), 50W out FM transmit on 467MHz, receive on 462MHz. Note that 1-7 are rated ERP (so are affected by antenna gain; if you have a 3dBd gain antenna, you'd have to limit the output power to <2.5 to stay within the ERP); main channels are transmitter output -- feel free to put up a 9dBd gain antenna for an effective ERP over 200W and closer to 500W!. The "middle" if all you mean is simplex would be interstitial 4, or main 18&19 (4 is between those two). But that is only considering simplex on 462MHz. You can't transmit on the middle if you try to cover both 462 and 467MHz (the "middle" would be around 464.500MHz). If you don't use repeaters, no problem (and you probably don't need to run on high power either, as low will match most upper-end hand-helds which may be what is being used in the field). If repeaters are a primary usage, you'd want to tune the antenna closer to 467MHz (but not so far as to make 462MHz unusable). Otherwise -- having duplex RP15 and simplex 22 showing similar SWRs would optimize the antenna (though you may not like either SWR, and simplex 15/RP22 will be even worse). The good news... You need to /shorten/ the antenna (though as I mentioned, maybe relocate it first before checking SWR). If the set-screws don't let you lower it enough, you can grind off a few millimeters at a time until you acceptable SWR readings.

The answer to your question is "NO" .. Weird that after so many words, the question still had not been answered.

I had a KG-1000G in my Jeep and in my wife's jeep pretty much since the KG-1000G was released, until just recently. We go off-roading every weekend, often/usually in the southern california desert where 103°F was normal. I made sure that both were mounted with good airflow on all sides, and where they would never be in direct sunlight - never once did we have any heating/over heating issues.. I was actually more worried about dust getting into the innards, but that was never an issue either. Worry less and enjoy the radio!

Forgot to mention..Thanks for reminding me... Always beware of the "some people" that try their best overcomplicate everything.

True, but impedance mismatch causes higher swr, so you're ... kinda doing that in a roundabout way?

Personally, I like this idea. However, I suspect it will be controversial. May I suggest that rather than adding this to the official repeater listing, you could create a thread in the Private Discussion topic to report member discoveries. In that case, other members with more information, like the owner does not want it used by others, or it is officially open, etc. could also contribute.

Minor nit-pick here... When I go to the shop area on MyGMRS.com, I seem to be stuck in there, as in there is nothing to click on to return to the main root page of mygmrs.com. Clicking on the HOME link returns me to the shop home page, as it should, but clicking on the MyGMRS.com logo on the top of the page also returns me to the shop/mygmrs.com page. I think that clicking the main logo from the shop home page should return to the main site page rather than shop home again. Same with forums as well. while clicking on the top logo from a thread page, it is nice to go back to the forum home, but clicking the main logo from the forum home page should return to the main mygmrs page. Right now, clicking the logo from the forum home page goes nowhere, just re-loads the forum home page.

I hope to write some of these at some point, just waiting for the site rebuild

How about some how to, or tutorials, on basic topics. GMRS is mainly aimed at non technical people who simply want a good means of communications and don't have much interest in the theory or radio as a hobby. For that there is Ham Radio. For example one wants a mobile installation. Basic info on how a mobile radio should be wired up for electrical safety, battery connections, fuses etc. What type of coax cable to use, cable connectors, antenna location and antenna mounts. Recommended mobile radios, antenna manufactures and models. Some sample photos of other people's installations for ideas to go along with the written material. Another would be for portable radios. Recommended manufactures and models. Issues with using a portable radio in a mobile setting, speaker microphones, heat sets, battery types, battery eliminators, cable adapters from the portable radio to mobile antenna. Again some sample photos. Repeater operation. What are they used for. What specific channels are reserved for them. Explain why there are two frequencies used and in general how this is programed in to the radio. Explain what a "PL" tone is used for and why it's typically required. The how to's should be kept at a low simple technical level. The idea is to help somebody setup a functional radio installation without getting mired in a lot of theory. After the system is up and running there is plenty of time and people who can provide additional info for those that have the interest.

Since the OP asked for opinions, I will offer up my opinion. I disagree with his statement that more GMRS repeaters are needed. In my opinion, GMRS is not a hobby, it is a service primarily intended for short-distance communications, to facilitate the activities of the licensee’s family. Since that intended purpose comes directly from the FCC’s definition of GMRS, I don’t see why we need more repeaters. My opinion is that GMRS is not ham radio. It is not CB radio. But the high profile GMRS repeaters in my part of the world are used by people that already talk on CB, and on ham radio . The conversations are exactly the same, regardless of where they talk, so why do we need to waste precious bandwidth on GMRS for those conversations, when we already have other band allocations for that ? For those that believe GMRS serves a function in civil emergencies, I would also direct you to amateur radio, specifically the ARES/RACES groups that provide those functions. Again, I believe we do not need to duplicate these functions across radio services. It is fine if a local neighborhood repeater such as mine could serve people in a time of need, but that is not it’s true purpose, and I don’t have lofty goals of making it that way. And most people within the couple of miles range of my repeater would not have access to repeater-capable radios, and likely only have FRS radios, so it would be of no use in that case. My repeater covers maybe 4 miles…on a good day, and only with mobile radios (hey, GMRS stands for General Mobile Radio Service, not “sit in my easy chair with my walkie talkie and talk to someone 40 miles away via a repeater”). It serves the needs of my family for short distance communications. We do use Zello as a means to extend coverage, if necessary, but it is again only for the family…not for a guy in Michigan to ragchew with a guy in Florida, or to hold “nets”. This is exactly why the amateur radio service exists, and where these activities should take place. A nearby GMRS repeater is connected to the MyGMRS network, and it simply transmits conversations of people not even within the state, all day long (not really all day, just exaggerating to make a point). A nearby ham repeater is connected to the America Link network, and transmits conversations of people not even within the state, all day long. What is point of having these broadcast stations, when local users are not using these repeaters ? We do not need more repeaters for GMRS. We need fewer people that think GMRS is CB or amateur radio.