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Since it’s been a year and I’m still dabbling in GMRS I decided to splurge on 50’ of LMR400 to connect to the J-pole on a stick that I showed previously. It arrived today and I thought it was time to do a test. This is just a relative comparison test. Checking the output of the radio I was getting about 9W as a baseline. I connected the radio to the Surecomm with just a rubber ducky antenna on the antenna side recognizing that this is not a good combination but it was consistent for the testing. Using the RG8X I measured 1.37W at the end of the cable. Next, I did the exact same test with the LMR400 and got 6.07W. I was surprised at the results so I did it again and saw the same. I realize that the LMR400 is a better cable but I did not expect to see such a large difference.

This! Absolutely nothing unusual about the results.

Tuning a duplexer for a single pair gives the best performance with minimal insertion loss and better isolation from other frequencies/channels. Yes you can tune a duplexer to cover all eight GMRS repeater pairs but that is a compromise. Doing this increases insertion loss and reduces isolation. Both will lead to poor performance. And the whole point of a duplexer is to isolate the repeater pair from other frequencies/channels.

All I got was a card and love from my family.

I guess I can justify my LMr400 cable as a Fathers Day gift (even if I ordered it last week).

Some Repeaters, I.e. my Hytera's, can be set in programing for IP transport basically linking them. Many Commercial repeater radios can also do this.. Although not legal in GMRS many commerical repeaters can be set in this fasshion but requires like systems.

People epoxy sheet metal to the underside of toppers all the time. And that works fine for a ground plane. Having good contact between the NMO mount and a sheet metal ground plane is what matters.

Due to there being a 5MHz spread between the uplink and downlink, you can make a custom duplexer that would be low loss and provide great separation, but you would have to have a pretty good understanding of electronics and how LC networks work. I am unaware of any commercially available, but if there is one out there and configured to tolerate any reasonable power, it would likely be well over $3,000. I wouldn't be shocked if it was more like $5,000. Actually, the repeaters available from companies like Midland are as expensive as they are, and have such low power, due to having a broad frequency duplexer that covers all channels. They tried to make them as efficient as possible without pricing themselves out of the market.

Here is the difference between the 2730A and 2730B for those interested.

An old thread brought back from the dead. The 2730A is a nice radio. I do find that it does not do so well on GMRS with the MARS MOD compared to other modded/unlocked radios or Type 95 certified GMRS radios. I can highly suggest the 2730B with black screen over the 2730A with its white screen. The $50 difference is worth it. The 2730B screen is so much easier to see in bright sunlight and easier on the eyes at night.

The Kraken system is like a child's toy when compared to what federal agencies and the military have. Even the equipment we had in the 90's was still better than the Kraken. We had no problems triangulating exact Iraqi positions back in 1991. And don't think for a minute that the feds are not using that kind of equipment right now. Transmitting briefly is standard SOP when using any military radio and has been for a long time. Transmit too long in a combat zone and you will get a missile or artillery rounds down your throat.

that was the idea when using the AN/PRC-90. I just missed the AN/PRC-103 that was a pretty good improvement. There was a movie about a downed flyer. There radio discipline was pretty terrible and had they used the radio as much as they did in the movie it would have died or the flyer would have. The north Vietnamese knew what frequency to monitor.

Transmit briefly and move frequently.

You need to look out for those krakens...

RG8X has around 86% loss over 100 feet while LMR400 has around 48% loss over 100 feet. Plus the fact that the center conductor, insulations (dielectric) and shield braid are bigger with LMR400 which helps reduce loss. @WRDJ205 your real world measurements are close to what most online coax loss calculators will show. While a j pole is not the best antenna, they work just fine. I've seen enough home made UHF j pole antennas built from solid copper wire that works well. No they won't have as much gain as other designs but nothing wrong with a J pole.

The availability of those repeaters covering multiple frequency pairs is what brought this question up. I was curious why the packaged repeaters were able to cover multiple pairs when the one on BuyTwoWay had to be tuned for a specific frequency pair. It seems like it’s somewhat of a compromise but you get the convenience of a pre-packaged unit. Something to think about.

some Radios do have GPS and transmit their coordinates to other grouped radios but only when the feature is programed or activated in the radio.. Some of my radios have GPS features but i dont have them programed in my radios, therefore none of this data would be transmitted from my radio.

Curious. Don't some radios now have GPS? Would these retain data? Do some radios possibly have GPS unbeknownst to the purchasers that logs data?

Oh... oops. Yeah that makes more sense. I only looked at the original poster's text and they typoed it like: "6/1/1/25" (extra dash in there between the ones! )

FCC data base shows it was issued on 6.11.2025. Take another look at the date he posted - It's not 6.1.

The duplexer and cables in itself will cause you to lose approx. 30% of inserted power. If the duplexer is not tuned properly, you will lose more of your inserted power and you may be very well left with just only a handful of milliwatts of output power and that will affect your Farz.

@SteveShannon Thanks a bunch for the link. I did try to search just like that poster and read several of the results but did not see the one you sent. I have some reading to do.

I would say a 2 way radio is harder to find than a cellphone is. You can ping a cell phone at will with the proper equipment and have it give it's position away. You can't do that with a normal 2 way radio.

Not sure why all the concern about phones. If you are there someone likely recorded you on their phone and has already uploaded it to social media.

It could be a number of different things causing the noise. Knowing what vehicle he is using and how it is powered will help. All of the LED bulbs and computer modules on newer vehicles can cause noise. I had to put clamp on ferrite beads on the wires powering my radios and I even put one clamp on ferrite bead on each end of the main wire going from my alternator to the battery on my 2023 Ford Escape. I still get an occasional whine when transmitting. But it doesn't happen often enough to chase down the source. Another thing people sometimes overlook are al of the LED street lights and LED bulbs used in homes. I know the cheap LED lights in my garage are very noisy on 2m, 70cm and GMRS. I don't dare try to use any 2m/70cm or GMRS radios inside the garage with the lights on. Power transformers are another source of noise if they are starting to go bad and/or have bad connections. Solar panels are another source of noise.

More information will allow us to help you better. Noise can come from many sources. Alternators, spark plug wires. cheap LED lights, using an accessory port, wiring directly to the fuse panel, etc. The best way to connect any two way radio in vehicles is to run the radio's positive wire directly to the positive battery terminal while running the radio's ground wire to a chassis ground. You do not want to use the battery negative terminal, especially on newer vehicles equipped with battery management systems.

FM CB. FM. He said no one used FM CB. and he would be correct.

yea, couple hours ago i was goinna take a drive by a couple cell towers to do close proximity test, but the damn beer won my attention

The higher the frequency the shorter the wavelength and the smaller the opening that can penetrate.

Just program them in groups. 1-100 is GMRS and 101-200 is MURS or whatever. That way you don't need to remember a weird channel number. Always starts from 1 and goes to 100. Just ignore the 100 on the MURS.

I'm NEW NEW with beginner knowledge and I built a Simplex Duplex Box that duobles as a GMRS specific Box. I can swap my Rx radio out with another that has a audio relay which turns my box into a repeater. So absolute no, you don't have to have "advanced knowledge". You just have to learn the process and put it together

I only use folded dipoles on my repeater systems and I find that 50' of vertical separation is good. So for my Rugged system, I have RX at the top at 300' extending to 320' the TX antenna is at 240' extending up to 250' My my 2 cents

Access is not bad. It is on the circuit board that is behind the front panel. With the top and bottom covers off, the front panel pops off via a couple of clips. Then a couple of screws hold the board in place. You don't have to disconnect the ribbon cable; just flip the board over. It also gives you a perfect opportunity to pull the keypad out and clean it. Or better yet, replace it with a nice new, white one that is intended for the 863G. It fits, is not expensive and in my opinion, the white keys look better. Software programming is simpler than FPP. FPP is just something that is nice to have, just in case. I didn't expect that Used Radios would remove the resistor. But if you can get them to enable FPP in software when they program it, if you ever get around to removing the resistor yourself, FPP will then work without any further software programming. In that case you could add a couple of additional channels to your existing 15 channels, without ever needing to connect it to a computer. If you get your ham license and want to program some ham frequencies in your radio, you will definitely need to be able to program it yourself. You will also need to tweak a couple of things in the radio to get it to work properly down in the ham band. It will still work fine on GMRS, too. I've done that on a few of them too, so just hit me up for the info when you need it.

If you get your ham (not HAM; it's not an acronym) license, those of us who are hams will be happy to offer guidance on setting up your radios accordingly.

Yes, absolutely.