WSAM454

If it is a GMRS only radio, and there is no way to "unlock" it ( look it up ) then it will only offer the 5MHz split, since that is what is used on the GMRS band. If it can be unlocked, then you might be able to enter the needed offset, but make sure you would be welcomed on the repeater, since it does not sound like a typical GMRS repeater, and if it is, then it should be using the standard GMRS repeater offset.

These "400" cables can get confusing. The RG-400 you mentioned is a small diameter teflon Mil Spec cable with a 400MHz loss of over 8 dB/100ft. https://www.awcwire.com/rg-catalog/rg400-coax-cable You probably meant to write LMR-400, which is the agreed-upon default cable at a moderate price, for UHF operation with low loss.

Good info, but the recent assumptions and loss figures are for a 50 Watt radio, and the OP never mentioned how much power he will be running. Bottom line is to go with the RG-58U for better flexibility and easier installation.

While the thicker cable will have a lot less loss, you are dealing with an approximate 20 foot run, and the thicker one will be very difficult to route. Unless you are using a 5 Watt radio in the car, I would go with the RG-8 or 8x cable. As you will see from Steve's link there will be a good amount of loss with the thinner cables. While the thicker cable will have a lot less loss, you are dealing with an approximate 20 foot run, and the thicker one will be very difficult to route, so the thinner usually wins out. Unless you are using a 5 Watt radio in the car, with a loner than 20' run of cable, I would go with the RG-58 or 58x cable.

Does that small metal disk make an adequate 'ground plane" for the antenna to work against, since it would appear that the adhesive will insulate the plate from the actual metal of the vehicle? OP. how about a lip mount that might fit somewhere on the hood lip, since you do not have a trunk.

Good idea; especially if you are going to run the HT radio (lower power). An outdoor antenna will give you much better/reliable coverage, and the meter can come in handy to make sure it is tuned for the right part of the band. The SW-102 should do nicely.

I think they are referring to the meter itself. Some are digital (have a numerical display) and others are analog (Have a traditional mechanical moving pointer movement.) Some users prefer one type of display over another, and feel that the digital is more accurate. As '381 said, just use the screw-on antenna(s) and don't worry about it. You can use the meter (either type!) to check the SWR on your outdoor antenna and to monitor the power output from the radio if you leave it connected in-line between the radio and the antenna cable. Of course, the meter you use has to be able to measure at UHF (450-480 MHz) frequencies, which the SW-102 can, and it has a digital display.

Thanks for the responses; looks like the Comet is the way to go! Now to find someone local to do the install for me and acquire the equipment. (I am no longer good on towers and ladders.)

I know it would be a compromise, but any suggestions for a base antenna that would cover both the VHF/UHF Ham bands and the UHF Gmrs frequencies, or do I just choose one and put up with the mis-match on the other band(s)? Looking at the Comet and Diamond sites, I could only find service-specific antennas. I have only one mounting position available, about a 40-50' run of coax from the shack.

There are MANY choices in a mobile radio that you have to consider, so it is difficult to make an actual recommendation on a specific rig. For mobile, of course, a good antenna, securely mounted, is needed. I would suggest a trunk lip mount if you don't want to go the permanent (hole!) mount, and to avoid the mag mounts. If the antenna is going to be mounted on the side of the vehicle, I would suggest the left side of the vehicle; being farther from tree branches at the curb, and kids' hands! As to the actual rig, in a mobile, the physical size and power level are important. Since most vehicles don't have much room for a radio you have to consider where and how to mount it. You also have to run DC power to the rig, and that should come from a heavy (10-12 gauge) cable from the battery. For low power (10-20 Watts) you might get away with using the 'cigarette lighter' socket on the vehicle, but much better/safer to go right to the battery no matter what the power level. Radios can vary from about 15 Watts up to the legal maximum of 50 Watts. For mobile use, something in the 20-40 Watt range would be ideal. With some you can vary the power as needed for distant and local contacts. You have much to consider; I would look at on-line reviews of radios from the popular makers, since you are not on the air yet to ask for local opinions! Some you-tube videos from the more popular posters can also be helpful. Some makers of mobile type radios to think about would be (in no particular order!) Wouxun, Midland, Radioddity, Anytone, Alinco, and Retivis.) Of course there are others too. Some models may be made by one maker, but carry different 'brand' names, which can confuse things a bit. Hope you get some other advice; good luck getting on the air.

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.