WSAM454

If it is on top of a bookcase, is it near a wall or ceiling? Possibly try it in a different location, even if it is a bit lower, and see if that makes any change (for the better!) Any chance you have a window/wall airconditioner, and can put the mag mount base on it, which would also get the antenna outdoors, possibly more in the clear?

You said that you "...only went a couple of miles, as if we were only connected Simplex.." In those couple of miles, could you tell if you were both actually keying and going through the repeater? Are you sure you are within range of it and that the radio is putting out its rated RF?

At 1200 feet, what kind of wind loads and temperture/weather conditions will the antenna be subjected to? You might need something more 'commercial quality' to stand up the the conditions at the site.

Thanks for the clarification, Steve. For followers of this thread, I have found this site after reading your posting, and since it offers more coax choices, it may be more useful than the OP's. Scroll down near the bottom and there is a set of calculators: https://kv5r.com/ham-radio/coax-loss-calculator/

Well, not wanting (or able to) get into the actual math, LMR 400 has an approximate loss of 3dB at 450 MHz, and RG8X has an approximate loss of 9 dB. That is a 6 dB difference, which translates (roughly!) to 1/4 the power level. So an ERP of 40W using LMR 400, according to the chart, will have an approximate ERP of 10 W using RG-8X.

so.... you were in the wrong group?

Even easier; you can get the info on this site. Fill in the "License Lookup" at the far right top of the home page!

^^ Simple, easy explanation by '946. Also, the vehicle is painted, so there would still be no electrical connection even it the base of the mag mount were bare metal. The larger the area under the antenna, the more effective the "ground plane" will be as part of the antenna system.

Alternative to the cookie sheet on the roof is a mag mount on the top of a window or in-wall mount air conditioner, especially on the second floor.

Your Comet antenna is advertised as wide-banded, to cover GMRS and Ham frequencies, so somewhere, on some frequency, it may have a lower SWR, but as has been said, 1.6 is certainly not a problem.

Is that possible???

Agree on the higher power base stations. With good antenna height each should be able to communicate with the local hand held units, and from home, you should b e able to communicate with the other houses. The individual repeaters may not enable hand helds at the extremes (you said 30 mile radius) to communicate with everyone anyway, only with the most local repeater, so you still need a way to communicate house-to-house, and that may need more power than the low power repeaters you have in mind. Again, a lot depends on the terrain.

Yes, that is a good possibility, especially if the antenna shows the same problem with a different NMO mount. Could the ring be too large in diameter? Do you have another antenna that you use on the fender mount, and can you compare the O rings on the two of them?

Yes, that is not clear. Do you mean a repeater for each home, for each to keep in touch with individually, or 1 repeater to cover all the home locations consistently. If that, then it should be somewhat centrally located. Also, the average single- story home is about 25-35 feet to the roof,so 30 feet may really not be much height depending what else is around you. You would want to clear as much in the way of tall buildings, hills and trees as possible. Some mention height above sea level, but that really does not matter, what does matter is height above anything else in your coverage area, whether that area is 50' asl or 500' asl.

The first one has about 5dBi gain over the other, so it should 'hear' better.