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Hi All Thought I'd introduce myself. I'm John If this is in the wrong place please forgive me and feel free to move my post to a better forum/Thread. Been lurking and reading for a little while. I've picked up a GMRS radio and License to go in my Jeep for exploring the High Desert with friends as most are moving away from the old trusty CBs. I've been testing the set up in my DD and like it fine. In fact I am thinking of keeping it in the daily, adding one to the wife's car and a third for the Jeep. I see there is a repeater in the Mountain Home area near me I could hit at times when out exploring if I can get permission. Just wondering if there are any others in the Twin Falls area and the best way to find them. Also Anybody here in my area?

Based on your response, the fact that there is a remote potential to damage the GMRS receiver should someone transmit on 11 meters, I decided to take down the 11 meter antenna and will relocate it onto another building, at least 30 feet away. I put the GMRS antenna in it's place and that was the easiest thing to do on this near 40 degree, sunny day. Thank you for your reply, Dennis Goethe

Ooops I’m the owner of a couple machines in Idaho falls, and west Yellowstone, I also have a 220 ham machine set up on one of the mountaintops, Id like to see about helping out in twin... maybe linking sone machines up for a bigger foot print, both gmrs and ham 220.

Hello Dennis. The answer depends on what types of impact you are concerned about. Potential things that come to my mind include the following: - Impact on GMRS radiation pattern based on the adjacency of the 11 meter antenna. - Impact on 11 meter radiation pattern based on the adjacency of the GMRS antenna. - Impact on one receiver when the other is transmitting. * The 11 meter antenna is far enough away from the GMRS antenna that the GMRS antenna’s pattern will barely be affected. * The GMRS antenna is close enough to the 11 meter antenna that it may alter the 11 meters performance, depending upon where the antenna (and the mast below it) is located relative to the top of the 11 meter antenna. 2.75 meters (1/4 wave) is the minimum recommend horizontal distance that should exist between this antenna and another other metal monopole to keep effects minimal. * While transmitting on either radio, it is probable that you will experience serious desense on the opposing radio. If the operating power of the 11 meter antenna is high, you could conceivably damage the GMRS receiver, although I do not have any specific power numbers for your. When antennas must be mounted at the same elevation, is best to put as much horizontal separation as possible between them. When in close proximity, it is usually best to give them vertical separation and make them as close to collinear as you can so that the two antennas operate in the pattern null of the other. Experimentation is what will give you the absolute answers you seek. Hope this helps. Michael WRHS965 KE8PLM Edited for spelling.

This seems to be a common misconception and point of confusion. Do not confuse the idea of insertion loss with return loss They are not the same and people seem to commonly interchange the two when discussing antenna systems without realizing the difference. Insertion loss means exactly that, your RF energy from the transmitter is converted to heat in the coax and the various other hardware used to connect the cable(s) to your radio and the antenna. Good quality coax connectors have very low insertion losses. Return loss means that power is reflected from the load back towards the source. This manifests itself has an elevated or high SWR reading. The return loss is far higher on the PL-259/SO-239 type connectors on UHF and higher frequencies whereas the insertion loss maybe low. The mismatch is caused by the fact the connectors are not a "50 ohm impedance" thus causing the power reflections. The most common RF connectors to use on UHF systems that have low mismatch losses are type "N", BNC, mini UHF and SMA. While the mini UHF connectors look like smaller versions of the old PL-259/SO-239 the design is such the impedance is much closer to the usual 50 ohms. https://www.campbellsci.com/blog/ins-outs-rf-connectors https://www.arcantenna.com/blogs/news/how-to-identify-coaxial-connectors https://www.air802.com/connector-identification-chart.html https://www.hamradio.me/connectors/uhf-connector-test-results.html And for those looking for a bit more depth this book would be a good reference. http://www.w3pga.org/Antenna%20Books/Reflections%20III.pdf

N connectors are preferred. LMR400 is fine for NON Repeater use. Do not use LMR400 on a repeater. For your base at home you are fine. Get N based surge arrestors also.

If only the US offices based here selling the Chinese, Singaporean and Malaysian radios would just bring the manufacturing back to the US.... SMH.... I know everyone says use a Part 90 reprogrammed... Plentiful and low priced used units. I would love to. But at my age, with cancer, a year in jail for doing so is just too expensive, and with my medical conditions having a $10,000 fine would be impossible for me to pay... So I just bought a Part 95A/E unit. I am the guy that gets a ticket EVERY time I do 5mph over the speed limit. So I live with the FCC rules and buy an overpriced CCR radio. They seem to do okay for me. My ears don't hear too well either, so intermodulation hasn't been detected by them and "hi-fi" wideband FM is a waste with my hearing. I have a Wouxon KG-805G handheld and the Midland MXT400.... I am tempted to get a couple of these CCR's and a duplexer just to see how well it works. I know for some, it is like a religion and they are very devout, something like the whole Chevy/Ford debate in the auto discussion groups, it is getting like the whole left/right political environment... Everyone just seems so passionate and devoted to a singular view with a closed mind approach. It actually makes me want to duck out of here. SO.... I think I will just talk about my home brew antennas... They are made in the USA... LoL