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Thanks for the article Marc! I really liked the Dougnut analogy! The analogy I used to explain antenna gain to my brother was to imagine an inflated ballon that was being squished from the top and bottom, the sides will expand out further to compensate for the applied squishing to the top and bottom. It was also way less messy using the ballon as a physical prop instead of a dougnut!

That brings to mind the "Coffee Breaks" my local CB club would organize on holidays. We'd set up at an Interstate rest stop, or perhaps a local mall parking lot on a major US Highway, and serve coffee, water and donuts to weary travelers.

And, if the SWR on both is 2:1 or lower, seal everything up put away your tools and leave it. If you keep trying to “fix” it you will end up with an antenna for the 100 gigahertz band.

There are a couple of techniques. I personally tune for the center frequency of the band I plan on using. To be sure you are centered, you check the highest frequency you will use and the lowest frequency you will use. If the SWR is the same on both, you are good. If the SWR on the high frequency is higher than on the low frequency, your antenna is too long. If the SWR on the low frequency is higher than on the high frequency, your antenna is too short. The biggest problems you will run into with GMRS antenna tuning is, unless you have an antenna analyzer, that method is tough to use since you can't tune to the center frequency. Also, in centimeter radio, if you trim the antenna as little as 1 millimeter, you can drastically change the SWR. So, its a slow process and easy to mess up an antenna.

Back in the old days, we used to have "CB Jamboree" events out here in the midwest that would bring folks in campers & RVs from across the nation. Perhaps one of these days, (not soon due to Kung Flu) but one of these days someone could host a "GMRS Jamboree" for the same purpose.... get together for fun, food, and fellowship - and have a big swap meet to swap radios, antennas, parts, and bushel baskets of bull.. uh, chips.

That is the most politely anyone has ever told me that I'm full of crap. LOL

You are correct an I will correct it. Gain factor of an isotropic antenna is 1.0, not one BD... typed a lot. type-os happen. You guys are killing me, though. I specifically said I didn't want to science it up so I didn't confuse people. SMH Explain stuff like a little kid is reading it so people who have no idea what is being discussed can at least comprehend the general concept. All that stuff you guys posted is wasted on me. I already know it. The target audience is not going to have a clue what you wrote means. EDIT: That's not true... what I described about the radiation pattern and its general shape as gain increases is correct. I buggered a type-o. That doesn't make the rest explanation of incorrect.

I have one and have had it up and running for several weeks. It is posted up on a mountain near me putting it around 1800 feet up. It is powered by a 14 amp hour SLA battery that is solar recharged. I have a simple N9TAX roll up SlimJim for an antenna. It's all just strapped to a tree right now; exposed to the weather. The solar controller draws .01 amps. The RT97 draws .08 amps during standby. The RT97 draws 2.05 amps during 10 watt transmission. It reaches out 20-25 miles easy but again, it is at 1800 feet so my line of sight is great. I have been super impressed with it. It is a great option for off-grid repeater operations. I would include a few images but I don't know where to host the images anymore.