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Some people seem to have a hard time grasping the idea of a frequency offset between TX and RX and can't get into their local repeater either.

Yep, nothing beats a great well thought out install. I won't tell you how many whips I went through on the F150 due to low indoor parking, even took out a few fluorescent tubes as well and no sheetmetal distortion!? A bit off topic, but here's what I did for the two motorcycles I have. The red 2018 Goldwing has Larsen NMO2/70B and NMO27 on a custom antenna mount that I fabricated. The blue 2014 Goldwing Valkyrie just has a Larsen NMO2/70B on a custom mount. Both bikes have a Kenwood V71a running full output with good SWR. Here's what one of the mounts I made looks like prior to installation. Coax for both antennas is RG400 with N connectors. And the V71a head mounted in custom mount that allows me to slide the head in and out when I'm away from the bike.

Just use a quality mount and you'll be fine. I have 6 NMO in the roof of my work truck with no issues.

Once I became a Premium member that limit seemed to go away.

You are going to be looking for a MTR 2000/3000 or a Quantar. There is the GTR8000 but those are hard to find and very expensive, so I would consider them outside the realm of a hobby GMRS / HAM repeater in all but the most well funded groups / clubs. I would advise the MTR over the Quantar as they are a bit less expensive but are mostly the same electronically. Gonna see similar performance from either. I will say this, the MTR software will not run natively on Windows 7 or above. This creates a small issue that needs to be addressed. But finding a Windows XP laptop isn't a bad thing regardless as there are numerous other radios that you will need an XP or even a DOS machine for. An old laptop set to dual boot between DOS and XP is a very handy thing to have as a radio hobbyist. There are two versions of the MTR platform. One is 40 watt and the other is 100 watt. DO NOT get it in your head that the 40 watt units should be avoided since they will not TX 50 watts. The difference in performance between 40 and 50 watts is NOTHING. NO one will know the difference and it's not going to add any measurable distance to the coverage. If you don't believe me, go download Radio Mobile and run a coverage map from a tower site, run one with a 40 watt transmitter and then run the same map with a 50 watt transmitter. The second thing you need to be looking at is a GOOD duplexer. The little 'mobile' duplexer's work ok for a small setup that's not got much antenna height or is NOT in a high RF environment. Those will cost you coverage on receive due to allowing out of band RF into the receiver. That OOB RF will cause the first RF stage AGC to lower the gain of the first RF stage and make the repeater less sensitive to incoming signals. So you need to be looking for a pass / notch duplexer for a tower site install. I would advise against jumping into this with both feet straight away and instead setting up a repeater at your house or some spot you have access to. Get a feel for what it takes to do it and how much effort it takes. The other thing it will do is get you familiar with the money it takes to put together a system and get it on the air. EXPECTED COSTS for a large repeater system. I am looking this stuff up on eBay as I am writing this. So these are the expected costs for USED gear. MTR2000 UHF 100 watt repeater $1000 CELWAVE DUPLEXER $600 7/8 cable around 3.00 per foot used if you can find it. 7/8 cable connectors $30 each DB-408 antenna $100 - $200 another 300 in misc stuff Then a tower crew to install the antenna and line on a tower. Looking between 2000 and 5000 for that, at bargain doing yo a favor prices. Not Cheap.

Superb advice, thank you. No moonroof. It's an XLT SuperCrew, very lightly optioned, but with the 5.0 twin-cam four-valve Coyote V8. I bought the truck for the engine alone. Hard to find, Certified PreOwned, at the time. I looked through 110 trucks before I found it, then raced to the stealership with a large down. Love this thing. I don't know what the lateral B-pillar to B-pillar bracing looks like but I know it's there from another install found online. Because of that bracing I had thought to place the antenna centered in all directions between the B- and C-pillars. That would give some forward-facing bias in any radiation pattern, such as your install, and which was what I had hoped to achieve if I had used that Larson third brake light plate shown in the OP. Anyhoo... Yours is a great installation! I really like your mic connection! in the console nook. That's very cool. I had thought of the flip-down sunglass compartment, but my KG-XS20G-Plus does not have a removable faceplate (like your HAM or the KG-1000G or any other decent radio) but the XS20-G is almost small enough to fit up there with some work. Maybe. I am thinking on top of the dash using BuiltRight Industries' mount, but because there's sunlight exposure there, to make an insulated shade for the radio for when I do not remove it from prying eyes (which would be often) when parked. We'll see. Pondering it all, currently. Your motorcycle rigs are outstanding! Thanks for all of the photos. It is appreciated, as is the support.

It's truly a wonderful thing about antenna design, isn't it?

It gets a bit more confusing when you include gain antennas in the mix. For example with a simple 1/4 wave antenna lets say your S-meter reads 2 S-units. Then switch over to an antenna with 6db of gain now your S-meter will read 3 S-units. Nothing on the TX end or path changed other than your antenna.

If CTCSS tones are used when transmitting, they can be scanned. But, there’s nothing that says you have to use the same tone as the “input tone” on the receiver side. But, someone within range of a legitimate user can still scan for the input tone and use that to gain access. I don’t know about scanning for DCS tones, but I assume it’s the same. In GMRS, there’s no foolproof way that I can think of to prevent unauthorized access and no radio is jam proof. You can change tones frequently, but that will inconvenience your legitimate users. There are a few forum posts by people who ended up taking their repeaters down because it just became too annoying.

I can't find pictures of my 2018 F150 but I ran dual antennas on that truck also. One Larsen NMO27 and one VHF 3db gain whip antenna. Traded in truck for my JT in 2020 and roof had no distortion or anything. Just popped 2 NMO Black caps on and dropped it at the dealer.

GR1225 is not a continuous duty repeater. The Motorola Quantar and MTR2000, GTR8000 are. I had created a post with some new out of box repeaters but only a few I would rely on for 100% continuous duty. I think you need to determine 100% continuous duty or q quality reliable repeater. A repeater than can stay keyed 24/7 is a step up from a good quality mid use repeater. Most repeaters sold are what I call mid duty. They may claim 100% but I've seen some keyed for a day and burn up a PA. Then there are home built ones out of mobiles that are not reliable to put at a tower site. Good for a garage home site.

Best way to go! A couple things to keep in mind before you start. Do you have a power moonroof? My 2013 Limited has one and putting it in the center of the roof wasn't an option due to the tracks for the glass panel to slide on, so I opted to do the third brake light area. I put the hole in there and added extra reinforcement by putting a thin fender washer on the inside to distribute and force that might impact the antenna. As for electrical performance, it has been great on both UHF and VHF. Even though my goal of putting it center roof wasn't met, I feel the performance would be close to equal. If you can put it center roof, hopefully you have a flat support brace so you can go through two sheets of aluminum. If not, definitely add the fender washer for added strength so you can use larger antenna antenna without worry. Here's what my ham install looks like. FTM-400XDR control head installed in sunglass holder for stealth. Folds up when not in use and looks totally stock with no radio in vehicle. Microphone plugged into jack installed in console.

Yeah, I've hit that limit a couple times lately too...I think @Sshannonmentioned running into the reaction limit not too long ago too.

I need something better so i can calibrate my Fars-O-Meter 2000! I am also looking at some of the MFJ's but I want something that "some people" wont declare is just 'junk' and i'm not sure where MFJ falls on the home-expert's scale of "just junk"...

FYI - I've had a page on how to program the Maxtrac using the DOS software under Windows 10 using DosBox in my bookmarks for awhile. More or less a step by step guide on setting up DosBox to use old Motorola software for the Maxtrac but should be applicable to most of the other old Motorola DOS software as well. https://www.nv9p.com/blog/program-maxtrac-with-dosbox

Kinda makes my head hurt.

Depends on who offers it. Our County Sheriff (Minnesota's Ramsey County) runs a first rate program. We met weekly for 3 hrs per session and took 10 weeks to complete. I just finished 2 terms on our city council so was well-acquainted with our law enforcement/fire services/county emergency services. As a retired federal employee I've taken previous courses via FEMA. I've also done some ARES coursework. They made no pretense of us ever getting 'called up' to handle a large area disaster (the pros will do that) but we could be called to handle things like crowd control and/or media coordination. But I did get a nifty backpack w/reflective vest, a green hardhat, flashlight and a multi-tool to close gas mains and break through tempered glass (vehicle rescue). Worth it.

I think you've just learned a valuable lesson about "some people" and online "Experts" ...

Many repeater support repeat enable and disable but many only support that via wireline connection. Some will support DTMF commands but most that require that will use an external controller for the enable disable. Use of a different input tone that output is a way some try to eliminate the use. DPL/DCS on input is a good way to do it with PL/CTCSS on output. Personally I find not advertising them on this site and other places keeps alot of the riff raff off the air.

I went just behind the brace that goes from B pilalr to B pillar for one pair of mounts. I would stay just behind or just in front and not thru the brace. You really dont need to go thru the brace and deal with the extra hassle of getting it mounted. This is a 2019 and I have no dimples or metal distortion and travel a lot (178K on it so far) so they get wind.

Funny story that no one normally sees. The front left puck is actually a GPS antenna for my APX mobile (one of 4 on the truck) but I mounted it exactly the same as the one on the right that's the sirus xm antenna. When this was installed the front 2 "pepper shakers" were 800 mhz but have since been changed to UHF 1/4 wave black antenex whips. The rear mounts still run a laird LTE on the passenger and a Larsen NMO27 for CB on driver side. All mounts are labled next to the NMO and match the labels inside. Wifi and other GPS are all glass mount in rear window and center of windshield.

@axorlov, @marcspaz, and @Lscott Thank you guys! That was a truly interesting exchange on the signal strength meter and modulation types. It made me want to learn more. I knew that each S unit is 6 dB change, but I didn’t realize it was based on an absolute reference uV value, although in hindsight I should have.

Is there any way you can get that antenna outside of your attic and up in the air above your roof, if even just temporarily for testing? Are the houses around yours just as high as yours? What brand and model of antenna is it and what is its advertised gain?

My guess is that all professional repeaters have that ability, but I replied to this separately so someone with actual practical knowledge and experience can answer.

Ah, a proper FM demodulation circuit includes a limiter stage designed to deliberately remove any amplitude changes, before the discriminator stage, so it response only to the frequency deviation. For good discriminator performance there has to be sufficient signal amplitude to achieve full limiter action. https://www.arrl.org/files/file/Technology/tis/info/pdf/8506025.pdf

A couple points here. Duty cycle depends on how well the transmitter can dissipate the heat generated when in use. A 100% duty cycle unit would have a large enough area that the heat generated will not degrade or shut down the transmitter. The duty cycle of a repeater will be affected by the air temperature surrounding the unit. Most are rated when the ambient air temperature is closely regulated to be about 70 degrees F. As the air temp increases, the duty cycle decreases while the inverse is also true, lower the temp and duty cycle increases. I'm going back here almost 50 years, but I remember an axiom that stated lower the junction operating temperature of a transistor by 10 degrees C and you double its life. Many of the commercial grade repeaters will incorporate the STUN/KILL mode where a specific code string can be sent to stop the transmitter until the restore code is sent. And, as to brands, there is a reason Motorola has the majority of the public safety business. It may be overpriced in comparison and incorporate proprietary software coding but, above all, its reliability is unquestioned. One of the agencies I worked with had a repeater that had been operating for close to 50 years with no failures. Around 2010 it was in an area that had a record flood and that old repeater was then stressed into operating at full capacity for a couple weeks during response and recovery. It came through with flying colors. The brand, Motorola.

Dude, are you just messing with me? I think I'm being trolled by Alex... at 3AM. LoL

Yes, I got my KG-UV9PX this past week and compared it with a friend's KG-UV9GX and the bodies are exactly the same.

Menu Option [51: FAN-SET] Fan Activation Setting Function: The KG-1000G Plus has a built-in temperature detection system that will activate a cooling fan as needed. There are three options. Options: TX / VHT+TX / ALWAYS Default: VHT+TX TX: The fan turns on when transmitting VHT+TX: The fan turns on during transmit and when the temperature of the radio is high. ALWAYS: The fan is always on. And, there is always the "option" to just cut the wires.....

Change of plans, here. After learning a bit more about what matters and what doesn't, I'm going to go through the roof of my truck, using the NMO pictured, soldered to 15' of Messi & Paoloni Hyperflex 5 .212" coaxial, with an M&P PL-259 on the radio end. I will have to dismantle the passenger side of the truck's interior to lower the headliner enough to work after creating the 3/4" bore through the roof, using a Laird X-Act hole saw. This will place the antenna in a better position to have a good ground plane and after the installation is finished it should look almost like a professional install... if I don't do a hack job, that is, and for the life of me I cannot set out to do that deliberately. I have standards! Trouble is, my skills do not often measure up to those standards... ? ?

Hi Fellas! New GMRS guy here from Northern Arizona. Call sign WRWA569 Running a Baofeng GMRS-9r

Yes, exactly right!

Looks good to me.

Good to know...I was under the impression that with tones set on ham simplex you wouldn't know if the frequency was clear before transmitting so it's considered bad form. I suppose it would be the same with GMRS, but that nobody really cares. I say this with my deep expertise and experience; I've been a ham for 2 weeks and a licensed GMRS user for 3 months, so everyone should listen to me.

OK three things: 1) "Ham" is not an acronym (unlike GMRS), so it's ham, not HAM. ? 2) Part 95 is a set of FCC *rules*, not laws. There is a difference. 3) Your statement about repeaters is incorrect. Why would 95.1751 spell out an exception for when a repeater didn't have to identify, if *no* repeater needs to identify? https://www.ecfr.gov/current/title-47/section-95.1751 But that's OK, because I can use my new favorite saying. "There's what the FCC rules say, then there's what people THINK the FCC rules say, and finally there's what people think the FCC rules SHOULD say." ?

Since this discussion is continuing, I will repeat myself from the previous discussion on hams using GMRS. I think it demonstrates that the amateur radio service is not providing the “service” it should be, to the community at large, in 2023. Many ham radio test questions are out of date or antiquated. They have no real purpose to the users who are entering ham radio, and these questions and tests only serve as a barrier. Some will say they want that barrier to exist, to keep out the unwanted, just as they did with the morse code requirement. To those hams, I say ‘get over it’. The days of most hams being aerospace engineers and having pocket protectors are long gone. Like it or not, we live in the here and now, and it is a “new normal”. It may not be better, but it is new. I thought there was a proposal in recent years to offer an entry level test of 5 questions, to give privileges on 70cm. That would be a step in the right direction for ham radio. What happened to that??? That is exactly what needs to be offered for entry level hams who only want to use an HT or mobile FM radio, with privileges only on 70cm FM frequencies. Give them privileges on 2m FM as well ! And in all reality, why do we even need test questions for those privileges, when it is basically the same as GMRS ? What do you need to know? You have a requirement to ID every so often, and you have to stay on these particular frequencies, and you would be limited to 50 watts TPO. No need to see if the applicant can recognize a resistor or a diode on a schematic. Who can do that today, with SMD components in everything? -/\/\/\/- is futile

Absolutely. It's a tough sell to get people to understand that for as many similarities there are between GMRS and ham radio, (push the button and talk, your voice comes out of someone else's radio), GMRS and ham are completely different in a lot of ways in terms of their intended uses and user base. It's more likely you'll hear someone on GMRS say real quick their Jeep is stuck again, but on ham you'll hear a 75 year old giving you 15 minutes about how his gout is flaring up for the fourth time this week.

Thank you for the kudos... much appreciated, my friend.

Yep, I can certainly vouch for that. Since putting a super high gain antenna high up, the analyzer was reading a massive noise threshold.... needed 2 cans (cavities) to bring it down to an "acceptable" level. I think the radio range these days, aside from more TX power, is also limited by receiver being overloaded by RF noise; b/c after finding out the noise threshold at my location I was blown away how high it was... so if you don't have a radio that has a tight front end you won't receive signals from very far... Don't sell yourself short, Marc, you are being helpful to others, and nobody knows everything.... point is that sometimes little tidbits like that are the eureka moment that makes it, even for knowledgeable ppl. G.