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I have a Repeater and my Repeater setup is as follows: Repeater - Vertex Standard EVX - R70-G7 403-470 MHz 40-Watt Analog/Digital - Tx - 462.625 MHz/Rx - 467.625 MHz Receiver Port Connector - Female BNC Transmitter Port Connector - Female "N" Connector Antenna - Laird FG4605 5 dB Omni-Directional tip at 30 Feet AGL Transmission Line - Times Microwave LMR400 27 Feet Total Run from the Polyphaser to a Termination Point at the Duplexer. From the Polyphaser to the Female "N" Connector at the base of the Antenna approx. 20 Feet, including a drip loop, not to exceed total length of 25 Feet. Polyphaser Lightning Arrestor with Gound to Existing Earth Grounding Point with 8 Gauge Wire. Duplexer - EMR Corp #65316-0/MC(5G) - six cavity duplexer with female "N" Connector ports. Duplexer Jumper Cables - Times Microwave Low Loss RG-8X Coaxial Bulk Cable 100 Feet in length ordered. Receive High Port - 14 Inch Cable Length with Amphenol #112533 BNC Male Solderless Connector (Repeater) and Amphenol # 172135 "N" Male Solderless Connector (Duplexer Connector) Transmit Low Port - 12 Inch Cable Length with Amphenol #172135 "N" Male Solderless Connectors on both ends. Antenna Port - 12 Inch cable length with Amphenol #172135 "N" Male Solderless Connector (Duplexer) and Amphenol #18211510 PL259 UHF Male Solderless Connector to Mate with Antenna Transmission Feedline with an Amphenol #AML-83-1J Double UHF Barrel Connector. (The Antenna Installer did not have a Female "N" Connector for a LMR400 Cable at the time of install so I was stuck with the PL259 UHF Male Connector) NOTE: ALL JUMPER CABLES WERE FABRICATED/ASSEMBLED BY A LOWLY LICENSED GMRS USER (ME) IN THE OLD PEOPLE COMMUNITY OF SUN CITY WEST ARIZONA

I don’t feel like GMRS is lower than ham and I enjoy the people here.

Yeah, looks right to me as well. I would have used a different antenna line (LDF4-50 hardline) but I have thousands of feet of it on hand and connectors for it so it's not just cheaper for me (I don't have nearly that much LMR400) it's actually free for the most part. If you happen to have a dummy load that you could connect to the duplexer in place of the antenna I would be interested to see what your power readings were with a dummy load on the antenna port on the duplexer.

Sshannon, Thank you. It worked! I searched Randy's site many times and probably just blew buy this video. Thanks again for you help. Nathan Huntley

I’m active in amateur rocketry and we use GMRS radios to keep track of each other when we’re recovering rockets. My GMRS radios are a Garmin Rhino 700, a couple of old Motorola FRS/GMRS handhelds, a couple Midland combo units, and one of the two DB20G radios that I have. My other one has been configured as a dual band ham radio. During the pandemic I started watching videos (too much) and I found those of Notarubicon enjoyable and interesting. Unlike some I enjoyed his dry humor. So I got my GMRS license. I had been planning to anyway, but never got around to it. That led to an awakened interest in radios in general which led me to get my ham license. I don’t really remember how I found this forum but I’ve enjoyed it. I’m not active on any ham radio forums. I haven’t even visited any other than a couple group.io pages specific to my radios. Radio is radio and I find it fascinating.

Hey Shannon, Thank you the follow up questions and trying to figure out what's going on here. But I'm going back to having a base station with one radio and a mobile radio in the truck. I got more enjoyment out of that. Maybe someone will built a gmrs repeater in my area who has the knowledge and know-how for such. Thanks again WRXU693

Sshannon, Thanks, I'll try that.

Actually, your idea made a lot of sense. Just put news of pending service outages into the repeater information so it’s available in one place where people can look it up.

Welcome to GMRS the Great Mobile Radio Society!

Don’t you keep a database of the people you’ve granted access?

If your SWR is 3-1 that's a big part of it. Duplexers are tuned circuits that require a proper impedance at all points connected to it for it to work right. A 3 to 1 SWR is NOT a 50 ohm impedance. And it WILL screw with the functioning of the duplexer a lot. The KG1000 radios are not an ideal repeater setup to be sure.... but having that sort of mismatch on the antenna is certainly going to have an effect. When you tune a duplexer, you connect the VNA / spectrum analyzer to two ports of the duplexer. One port is obviously the antenna port and the other port is the side being adjusted. You then connect a 50 ohm load to the other port so the duplexer has a proper 50 ohm impedance on all ports. You can see the change in tuning when you connect the load if the monitor is already connected. I have never tried connecting a 75 or 100 ohm load to the port simply because there was never a situation that called for it. Without a proper service monitor with Duplex functionality, it would be hard to measure the desense caused by the mismatch, but I would certainly expect to see it.

If you are talking to 4 watt portables - who cares how much power gets through the duplexer? A "tight" duplexer tuning that loses more dB is preferable to a sloppy duplexer tune job that gets more power/less dB loss. Remember, you are using the duplexer to achieve isolation between the transmit and receive frequencies. Isolation is your key measurement - NOT power throughput. On most of these rigs built with an inexpensive notch AKA compact duplexer and 2 mobile radios, turning DOWN the transmit power will result in better overall range, less desense, and longer equipment life.

I have a friend with a Jackery as well. A Jackery is neat, but a poor substitute for a battery. The car port limits current to 10 amps, which isn't enough for a 50 watt transciever. If you crack it open and hook up an Anderson PowerPole extension, directly to the battery it would be more useful, but a battery in a battery box with Anderson PowerPoles is much more flexible: https://www.dxengineering.com/parts/wmt-58513-1403 Or this one from Gigaparts - it doesn't have PowerPoles but PowerWerx has fittings that might be useful: https://www.gigaparts.com/explorer-deluxe-battery-box.html and the batteries to put in it: https://www.gigaparts.com/p04power-12v-12ah-lifep04-battery.html or https://www.gigaparts.com/po4power-12v-24ah-lifepo4-battery.html Unfortunately both of those batteries are OOS right now, but if you look you should be able to find something similar elsewhere.

Hey, I am a super newbie here. I have a question. Maybe a couple of questions. 1. I am trying to reach local repeaters I have tried all of the ones that are open and input the correct tones etc but it seems no one can hear me and I don't hear much traffic if at all. 2. I DO however hear people talking from Arizona with people within 5-10 miles of me but again they are unable to hear me. I am in the San Fernando valley, Sherman oaks. Is anyone in this area that might have some insight? Maybe these aren't even questions... IDK. Any info would be greatly appreciated! I have a a couple of Baofeng GM-15 pro's and a Baofeng TP% I play with (Yes I know thats not a gmrs radio, I am just listening on it) S

Well, the truth is the antenna system more than ANYTHING else. You can have the most expensive repeater on the planet with an antenna at 50 feet and I can out distance you with a couple garage sale M120 radius radio's and a repeater link cable and an antenna that's 400 feet in the air. And you have to understand there are three measurements of height when it comes to all this out. First measurement is AGL. That means Above Ground level. If the antenna is on a 300 foot tower but mounted at 200 feet the antenna is 200 feet AGL. Then there is AMSL or Above Mean Sea Level. That is the height at the ground where the tower is above sea level PLUS the AGL level of the antenna. Then the most important one that is really important. That one is HAAT. Height Above Average Terrain. Now this one you are not going to measure with a tape measure. It's a multipoint averaging calculation. To figure this out, you create a circle around a tower out to some distance. I believe the FCC uses 20 miles but it could be more. Then you draw circles within that circle, typically 5 that are equally spaced. Then you draw a cross and an X through the circles to create the points of reference. The lines can vary from every 22.5 degrees to every 5 degrees depending on the type of calculation you want to do. You then get a topographical map of the area in the circle and document the ground level heights at every one of the intersecting points on the map. Add all those together, divide by the number of readings and then subtract the number from your AMSL. That will give you HAAT. The FCC website will do this for you, so don't think you need to do it manually. This is why an antenna on a 500 foot tower that sit's in a 1500 foot deep valley can be out talked by an antenna on a 10 foot mast pipe on any top ridge of the peaks above that valley. Sure the 500 foot antenna will talk gangbusters in that valley, but not at all outside it. And the 10 foot one will talk then entire valley plus down into all the neighboring valleys. We have one repeater on the MidWest system (Crete600) that talks 120 miles across it's coverage area. I have personally verified this by starting in Chicago and driving over half way to Indy before I fell out of the coverage area of that repeater. And it all has to do with the height of the antenna. Interesting EXTREME example of this. Ham radio has satellites that are repeaters. The repeaters are limited at 2 to 4 watts. They are 200 plus miles above the earth and you can hear them on a portable radio (HT) with a meager beam antenna. And you can also talk on them with the same portable radio and beam antenna.

DANG!!! That's what I want! Hard facts.

@WRYU810 You need to fix the TX on SCV575. You have it at .525. Also, the one above and the one below need to be fixed.

There’s no GMRS community (or GMRS repeaters) here (Butte, MT) but I’m active on 2 meter and 70 cm using a Radioddity DB20G. I am also active on HF using a Yaesu FTDX10 (160-6 meters @ 100 watts), with a short RG213 (HF has far less losses than UHF) running to my SWR/Wattmeter, then a six foot ABR400 jumper to a window pass-thru, which would really be bad in UHF). From the other side of the pass-thru is a 15 foot jumper to the 49:1 unun which is connected to my 66 foot wire which is 30 feet up on a Spiderbeam fiberglass mast. My BS and MS are in Engineering Science with an emphasis on controls, my PE (engineering license) is in electronic engineering but I worked on a section crew for Burlington Northern one summer.

It's in his signature.

Alright! Moved some stuff around all seems quiet for now though. I usually hear traffic mornings and night:

Just? As if that wasn't enough . Sorry I'm also a ham... even before I was a ham.

Oh.

I don’t have a repeater. I’m just a retired engineer and a ham.

Got it. Thanks. I may start another tech topic on jumpers that are used with folks who have repeater stations....that such be interesting.

Possibly the connectors?

None of the measurements you have provided indicate a problem with the duplexer, but they do indicate extremely high losses in the cables, especially for that length.

@WRYU810 A couple things come to mind. It is possible to hear a repeater that you can't reach. Repeaters are usually in a higher position and have more power and can reach farther than your radio may. You may not have the right input tone for what you are hearing. When you go to the map page click on the gear in the upper left hand corner and select offline and stale repeaters, sometimes repeaters are still active even though they show as stale. Stale just means that it hasn't been updated on the site in over a year. So you may be hearing some other repeater than you think. You may want to leave the RX tones off on your radio until you know you have set things up to access the repeater. By leaving the RX (receive tones) on your radio off your radio will hear everything on the channel you are listening to regardless of if it is coming from the repeater. How are you programming your radio for repeaters? Repeater channels are generally set up from channel 23-30, 31-38... by making sure you program in the appropriate location on the radio the required offset of +5 will automatically set. This will make your radio TX on 467.xxx and receive on 462.xxx. As for hearing Arizona, it's possible the repeater you are hearing is part of a linked system. If you can show us what you programmed we may be able to dial in what is happening better. I hope this info is helpful. side note, I have no experience with your particular radio so someone may have more insight on that than I.

Although you told us the brand, you didn’t really say what the actual length and type of the cable, such as KMR400. I really like M&P cables which are made in Italy and ABR cables which are made in the USA and Times-Microwave by MPD which are also made in the USA.

No bud. It's just too difficult with way too many variables without having someone that can physically look at what's going on and unfortunately gmrs hasn't caught on yet in my county.

I cant hit this repeater from my house even though I'm not that far because there is a mountain between me and the repeater, but when I go up to the desert I can hear it all the way up to Randsburg/Ridgecrest.. That thing has quite the footprint.

A car’s electrical system puts out approximately 13.8 volts while the engine is running. The charging voltage can be somewhat higher, even up to 14+ volts. That drops to about 12.5 when the car is turned off. Mobile radios must be able to accept all of these different voltages, but they are usually optimized for 13.8 volts.

Since you know for sure the CTCSS frequency, push the Menu button and step through the menus until you get to menu 13, which is where you set CTCSS for transmitting. Step through the tones until you get to the right tone. Test it with one of your buddies. Then do the same thing for menu 11 which is CTCSS for receive. This video shows how to set the codes, but it also shows how to setup for a repeater. Just learn about the codes for now.

The problem is that many (most?) of the inexpensive radios have a few extra CTCSS codes. That’s true for both FRS and GMRS. That upsets the numbering. What brand of radios do they use? It sounds like you’re using simplex anyway and the UV5R does have the ability to scan for CTCSS so just do that. In the meantime leave the tone out on the receive side and you’ll still hear your colleagues.

Sounds like the FRS radios don't use the standard CTCSS tone numbering format such as 67.0Hz. You have the right frequency for channel 7, the 11 part of the 7.11 might be tone 94.8 (Hz). If it isn't try to search for the privacy tone chart for the brand of FRS radio they are using. If someone has a radio that will scan for CTCSS or DCS codes you can use that to find the correct tone. Good luck.

Premium membership allows a person to generate repeater access reports that might be what you want.

Premium members have the ability to generate repeater access request reports. You can do them for all your repeaters or specific to a particular repeater and for all statuses or for a status of pending, approved, or denied. Maybe that would help you. I have no idea what information appears in the report or the format.

Welcome to the forum. Have fun!

A lot of fun and wierdness.

Welcome to the forum @WRYU810

It is a list of every repeater grouped by state that has a change. You simply scroll to the state, click on the repeater of interest, and see the latest status. It's very quick and easy to see if any of the repeaters I use are in the list. If they are, I just click and see what the status is.

A better radio choice is the DB-25G (Radioddity DB25-G GMRS Mobile Radio | 25W | Quad Watch | UHF VHF Scann) and for portable power, a battery box with a LifeO4 battery is much better. The radio draws about 8 amps while transmitting so a 1- 16 AH battery for less than $60 is a better choice. You can put in a box, like the Apache 3800 (3800 Weatherproof Protective Case, Large, Black (harborfreight.com)) and a cigarette socket (Amazon.com: CERRXIAN 12V/24V Fixed Thread Cigarette Lighter Socket Extension Cable,20A 13AWG Waterproof Cigarette Lighter Female Socket Replacement Cable-0.3m/1ft : Automotive) sets you back about $120.00. You'll need to put connectors on the cable to connect to the battery, but the socket can be used to both power the radio as well as charge the battery. All total, including radio is around $250 without the antenna.

FYI - I found horrendous amount of desense between two KG1000G Plus radios that were side-by-side. With a Motorola XTS5000 portable radio transmitting 3.7 watts, I only got .7 mile from the repeater on flat terrain, in otherwords just straight down the street before any turns until the mobile could no longer be received by the receiving radio when the transmitting radio was keyed. The TX out was no problem in being received by the mobile or portable radios. With a 50 watt mobile measured with 44 watt of RF output with a 2.4 dB omni mobile antenna with a VSWR of 1.2:1, I got about 1.8 miles. At first, I thought my problem may have been the duplexer or a cable or two but everything swept out good. I stopped the duplex function and I ran a test transmitting through the duplexer and the same antenna with one of radios in the simplex mode, and received on the other radio with a separate antenna and drove around using a portable and had great results and farz throughout the area of at least 5 miles away. I reversed the testing procedure of receiving through the duplexer and using the same antenna connected to the duplexer and still had great results as before. That procedure essentially eliminated the duplexer and cables as being the problem. However, I took the duplexer back to EMR Corp to have them recheck it and it was performing as designed and tuned. I reconnected the duplexer and ran my test again and still no farz with the two radios acting as a repeater. I called a friend and asked him to bring over his two Maxon radios configured as a repeater and ran my same test and used the same TX points and we got many farz. This test results proved there must be a desense problem probably due to poor shielding between the two radios. The function of the two radios were also reversed and that did not change the results. So, I learned my lesson in trying to go cheap. I decided to buy a real repeater station and installed it. On flat terrain, I got about 10-12 Miles with a portable and about 22-25 miles with a mobile radio. And my duplexer is still working great and has not burned out the plastic inserts like the cheap duplexers are doing. I called the selling Dealer, because the two radios were still under warranty, explaining the problem that I was experiencing and my testing procedure. The Dealer's Tech Support person essentially questioned my testing procedure stated that my testing procedure was not technical and scientific enough for me to arrive at my conclusion. I told him that I am not an engineer but it still was a real world in the environment testing with poor results from the two radios acting in tandem as a repeater unit and fine as separate simplex stations. Well his candor really gave me a warm and fuzzy feeling that I was in a favorable position so I just requested a refund. He stated that I need to ship everything back so they can conduct their own test in order to get a refund. Fortunately, I was able to sell one of the radios and for some stupid reason thought it would be a good idea to keep one of them for another base station. That was kinda of a mistake, oh well. Never again. I sold one of the radios to a Club member and kept one as a second Base radio mostly for monitoring two other nearby repeaters.

77 inches! I could replace my TV with that!

If you have purchased GMRS radios to 'make contacts' or to find strangers to talk with, then you have purchased the wrong type of radios, as talking with strangers and 'making contacts' is not what GMRS is intended for. It sounds like H.A.M. radio or the Grindr app might be better choices for you.