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Why does every new license holder want to setup a repeater? I would like to shed a little light on some of the important things to consider if you recently got your GMRS license and now want your own repeater. First thing to consider, are there any open well placed repeaters in your area that you are able to use? I can assure you most repeater owners want people to use there repeater. Owning several repeaters I can assure you all are welcome and encouraged to use my machines. Do you have access to a location to host your repeater? If your answer is your garage roof you should reconsider. Your garage roof will give you about the same coverage as simplex. Unless you’re on top of a mountain and all your users are at the bottom you will never be happy with this setup. GMRS is not as popular as one would like to think, unless your repeater covers 20 miles or more you may find you only have 1 or 2 users in the area. Unless you already have a group of friends together you may want to consider this before spending money on a decent well positioned site to install your repeater. So you found a nice high site and the price is right, all you need to do is get the repeater installed, sounds simple right? Some thigs to consider first and foremost are the costs because they can add up quickly. Are you on a commercial tower that requires a license and bonded climber? If so this could be by far your largest expense depending on your area. I have spent $600 to $1200 on a climber; I have had quotes as high as $2500 depending on the amount of work and heights involved. Keep in mind commercial sites require certified mounts, hard line cable, cable clamps, engineered grounding solutions and commercial grade antennas. No tower owner is going to let you install a comet antenna and 200’ of braided shield coax. This brings me to my next point, the antenna. Because of the costs involved with climbers you will want to expend your budget on the antenna. Remember a $2000 repeater on a $200 antenna is going to work about as good as a $200 repeater. Whereas a $200 repeater on a $2000 antenna is going to work like a $2000 repeater. On my first repeater I was gifted use of a 150’ tower, I installed a DB-420 on the top and 160’ of 7/8 hardline. Total cost of equipment for the antenna install was $2500, with the climbers labor coming in at an additional $800. This left me with enough to purchase an old Motorola R100 repeater running at 25W. To my surprise it had 30 miles of coverage, all due to the cash spent on the antenna and waiting for a decent spot. Things happen, more so if you have an antenna 200’ in the air with a conductive cable connected to sensitive electronics. Antenna issues, feedline issues, repeater issues all cost money and I promise at some point you will have issues that need repair and require your money! It is my opinion that the GMRS community does not need another 2 to 5 miles repeater as it just becomes background noise. What use is a public listed repeater if somebody in a mobile can’t use it 5 miles away while moving or the portable coverage is only a mile? If after reading this you are still going to build a repeater for your garage more power to you, just don’t expect 20 people to show up if it only reaches a mile. As the owner of several GMRS and Commercial repeaters I can attest to the amount of money and effort go into my repeaters. I have only touched on the basics, if you add in any kind of testing services, duplexer tuning, addition of a combiner channel to an existing tower system, RF engineering, rent and insurance your costs can sky rocket. The best advice I can give any new licensee is to try and use the available systems in the area. Take the time to learn a little about what you’re doing and to assess the usability of the service before investing in a repeater for the sole reason of saying you own one.

I have mentioned it before, but it still surprised me when my wife and I did some testing a few years ago. I have a GP-9 on a 40 ft tower at our ridge farm which is 1240 ASL and I drove my vehicle way down to the nearby Sidie Hollow, which is less than 900 ASL. These are deeply notched valleys (called coulees) in the Driftless Area of Wisconsin. Distance back to the farm was around 3 miles. With a cheap dual band 2 mtr/440 ham antenna retuned for GMRS, we could barely communicate. Switching to the tiny Midland mag mount 6 inch quarter wave, the signals became quite readable and one bar on the Midland MXT400's which we had on each end, running low power. Switching to the Midland mag mount with the "3 db" gain Midland 5/8 wave antenna increased it to another bar. Switching to the "6 db" gain Midland 5/8 over 5/8 wave increased it to another bar. I think we compared power levels from the lowest power setting to medium and that helped as well. I really did not expect to see that much of a difference. Especially when you consider that the gain antennas tend to put more signal closer to the horizon. It may be that the RF was bouncing around the hills and sort of filling in from different directions. I have no way of measuring the difference in db's for each bar. It would be helpful to have a ballpark number.

Given your physical location and your apparent need, general contact with other users and no immediate personal communications needs, you should seriously consider concentrating on ham radio. There are a universe of options available to you and several are likely to work well. You might even find there are ham repeaters near you. Just search online for ham repeater listings. Here is one such list https://www.repeaterbook.com/repeaters/Display_SS.php?state_id=78&loc=%&call=%&use=%

Yes, absolutely, Michael... hopefully I didn't convey it cannot be done, just the fact that placing two antennas on top of each other is not as simple as just placing one atop the other and letting it rip... Your comment about how commercial antennas are installed is spot on... but doing things like commercial installations means $$$$ and time... and then you need a lot of height, a good fiberglass mast, good feedline, using lateral extension to avoid feedline from messing with pattern... etc. I think the OP is better served by a dual band with a diplexer than going through all the hassles of a two antenna installation. Eager to hear about your results in your GMRS installation... what antenna do you have in mind? G.

The 5.5 dB claim is, simply put, not true. (also, if you don't see dBd or dBi its probably fake as well) That TRAM1173 (or MXT26) antenna probably has less gain than a simple 1/4 wave NMO, given the cheap coils used, and being only 2 elements, with insufficient phasing element separation between them (gain in collinear antennas is achieved by increasing the distance between the phased elements) not a chance in he11 it has 5.5 dBd... well, unless decibels dBs overseas are measured differently than in the rest of the world... that is. For comparison, a real world 5.5dBd gain is what a 4-bay folded dipole has, which is a massive antenna, and coincidentally, it costs a lot of $$$$$... too. IMO, and in my experience, for a car install, a simple 6" inch NMO antenna cut to GMRS frequency will work absolutely great, as measured. G.

Good Day IronArcher. I will let those that no better than I to do the explanation. Here is a link that provides a reasonably concise explanation. https://www.electronics-notes.com/articles/antennas-propagation/vertical-antennas/five-eighths-wavelength-vertical.php Now, as far a 1/2 dB goes that is absolutely insignificant. In real-world practical distance testing you will never, I say never, be able to tell the detect the difference, all else remaining equal. BTW, I own and use the Midland. I have zero complaints about it. and I was fortunate I did not need to tune it. It was perfectly tuned from the factory. I would buy it again. Hope that helps. Michael WRHS965 KE8PLM Sent from my iPad using Tapatalk