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There is a UV-5X GMRS radio that is the same form factor as the UV-5R series, and can share the same batteries. Unlike the UV-5R which requires an SMA-female antenna, the UV-5X GMRS radio requires an SMA-male antenna. This radio is supposed to be renamed UV-5G for future releases. There is also a dual-band UV-5X that does not share the same form factor as the UV-5R, and does not use the same type of batteries. As far as I know, though, it does use the same SMA-female antennas as the UV-5R models. When talking about the UV-5X radios, we should specify whether it's the GMRS version or the dual-band (ham) version. They are significantly different.

What does “duty cycle” mean? I bring up duty cycle every time I hear somebody talking about making a repeater out of cheap Chinese mobiles and worse any type of handhelds. Duty cycle is the maximum time an amplifier may transmit within a five minute interval, expressed as a percentage, to avoid overheating. Suppose a mobile amplifier is rated at 30% duty cycle. This means that it may transmit for no longer than 1.5 minutes and must remain off for not less than 3.5 minutes. Some people forget that a repeater is transmitting for 2 or more people, duty cycle will be reached quickly if you get into conversation. More people in the conversation just amplifies the issue. Once a radio reaches it's thermal design limits it will no longer be able to adequately cool the output transistors. Even if a radio is not hot to the touch the transistors are, in part because of the inefficient transfer of heat to the units housing or internal heat sink. The longer you exceed the duty cycle the more heat builds on the transistors, surrounding electronics and heat sink effecting it's ability to remain on frequency without spurious emissions. Exceed duty cycle long enough and you will need a new transmitter or radio. I have tested a few Baofang and TYT radios on my service monitor without great results. All of the radios started deviating outside of the allotted channel bandwidth after simulated conversation at 50% duty cycle, the longer I allowed this the worse if got. Testing was done using an Aeroflex 2975 IFR recently back from the calibration lab. GMRS is a tiny sliver of spectrum surrounded by the commercial land mobile part 90 service. It is important that any repeaters that are built or re-purposed are held to the highest standards and operated as to not cause any interference inside or outside of our allocated spectrum. I wont get into the part 90/95 debate but i do stand firm that non certified import equipment has no place on GMRS.

2.33 i dragged out my test equipment. Both at779UVs (one being the Radioditty) measure the same - full quieting is at -90 dBm and the pl tone modulation breaks squelch down to 100 Hz modulation - very sensitive. My tyt 8600 needs more modulation (300 Hz), as does my Anytone 778uv (200 Hz), and my Yaesu 7250D (300 Hz). The problematic repeater has 700 Hz of modulation, so it shouldn’t be a problem. Monday when I’m back at work I’ll see if the Radioddity unit too has an issue with that one repeater.

this is how i did the install on my 07 jkur. i installed the base under the factory infinity amp and remote mounted the head above the mirror, im using the 5\8 over 5\8 shorty.

From the quoted message it would seem like those radios are mine. They’re not. These are below. And this isn’t everything either. I have some base and mobile radios not in the photo. There are a few more HT’s I keep sitting around the home office too. The HT’s are mostly Kenwood, a few different Chinese and a few Motorola’s. Since a mention was made about digital I have radios for D-Star, DMR, P25 and NXDN so far. No System Fusion yet. What I can say about radios is you get what you pay for, and in the cheaper models maybe not even that. If you’re going to bet your safety or life on a radio don’t go cheap.

AK, Welcome to the forum and to GMRS. What do you want to test on your radio? From the other replies on the thread, it looks like you don't have anyone to talk to that is near you. Do you know anyone near you that has any FRS "bubble pack" radios (the ones from Walmart, Big-5, etc.)? If so, you should be able to talk to them using simplex (radio to radio) communication. This would allow you to test the functionality of your radio. If you're looking to test repeater operation, you'll first need to figure out what repeater you will use, and unless it's an open repeater, you'll need to get the owner's permission to use it. Anyhow, we can give better advice once we understand what you want to test on your radio. Once again, welcome to the forum.

CHIRP doesn't work for this radio anyway, sadly. The radioddity software is buggy, strange things happen sometimes when writing to the radio.

The XPR8400 is decent, but it is nothing more than two XPR mobiles in a box. The transmit brick has an extra set of fins attached to aid in cooling, but I wouldn't call it 100% duty cycle at high power. I wouldn't even call it 100% duty cycle at 25 watts, but I wouldn't be scared to run one for GMRS at 25 watts for 2 or 3 hours of transmit time per day. If you're looking for something smaller that will truly run 100% duty cycle at high power with digital capabilities, check out the SLR5700. I have yet to replace one of those because it burned up. If you want something for GMRS that's similar in price to the XPR8400 and is truly 100% duty cycle - check out the analog MTR2000.

Bit of a necro, but specifically.. You are supposed to use the minimum power required to communicate as a ham. It's on the test, lol. Seriously though, I can't imagine what you'd need 1500 watts for... Few of us have a 500+ foot antenna to stick our comms on to really get value.

I have both the Nagoya 771 and the Smiley super stick (and the stock 805G rubber duck). The Nagoya 771 and the Smiley (fully extended) seem to perform about the same and both are significantly better than the stock antenna. I think the Smiley retracted is at least as good as the rubber duck. As for the range of your 905G... There are lots of metal foils (on insulation and foil backed drywall) and "see through" metal coatings on glass used in commercial buildings and high rise apartments. Texas has a lot of intense sun and hot weather so many windows will have the metal coatings. These will just eliminate your GMRS signal. So I would not judge the radio by that. Take the radios outside and test them. Even our cheap FRS radios will do a mile... and that was inside the car with no external antenna. Terrain and metal surfaces are your two worse enemies. Vince