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In a number of posts on this forum I have mentioned my intent to side mount my amateur radio antenna on the same mast that I use for the GMRS antenna. I can now say that it is done and has been working for almost a week. As promised elsewhere, here are some pics. The side mount bracket is home crafted and painted a color similar to the main fiberglass mast. The amateur antenna is currently about 6-1/2ft below the bottom of the GMRS antenna. There is about 21” between the amateur antenna and the nearest metal (the GMRS feed line). I am using LMR400 feed-line for both antennas and have ferrite chokes installed over the coax. I have not yet detected any material interference or objectionable desense in the GMRS radio while transmitting on the amateur radio. I do however observe one bar on the GMRS radio’s meter flutter while transmitting at 50w UHF on the amateur radio, if the GMRS radio is receiving a usable low-level signal at the point I key up the amateur radio, just not enough to be of concern presently. I will be operating both antennas at the lower height you see in the picture until I am ready to guy the mast at full height, which is about 16’ higher. One of the inquires I received elsewhere is listed below along with my original response. Posted here to prevent derailing another thread. I will be running 50w UHF and VHF, 50w GMRS. I will let you know once it is operational. I may not have it installed for two weeks. I do expect some desensitization of the listening receiver while I am transmitting on the other service, but nothing that I expect will affect my operations. I will have ferrite chokes on the GMRS feed-line to cut down on the noise and reduce ingress from the 2m/70cm since that line will be running parallel to the amateur antenna. Michael WRHS965 KE8PLM

I don't know why some are trying to reinvent the wheel

Very true! They also set up hospitals with radios and antennas, I saw 10 antennas on a hospital and wondered why it had all of those antennas. I googled it and found out that Hams work with public health and safety to get them set up with coms on many bands in case of disasters. I do not know how many people need to be licensed at the hospital, but I am sure that there is at least a few. Hams are my hero, and soon I will be one of them LOL!!

I found the problem to my high swr on my gmrs radio. I was using the wrong connector connected to my new surcom sw 102 swr meter. it was reading 19.99 swr and now reading 1.4 or 1.5 swr and the watt output seems to be close using my 40 watt radio. Just a amature mistake. I am now so happy I can talk on it and not worry about blowing up my new radio. Now I have to figure out how to use repeaters. Thanks for all your help WRMZ 867 Bonner Springs Kansas

Seems to be some strong opinions on this subject, mostly folks that hate the feature. What are the pros and cons of using it? It's on just about every radio you see these days so I assume it's a feature that is needed. But I heard someone just a few days ago from an operator that simply asked for a radio check and he was berated for having it on.

The FCC has rules regarding antennas and their structure. If an antenna is not more than 20 feet above its supporting structure (chimney, tree water tower etc.) it's under the 6.2 meter rule. Antennas mounted to structures more than 20 feet in height should be registered. Antennas that are more than 200 feet above ground level (and that' the entire antenna to the tip) have to meet FAA requirements for lighting . As MacJack also stated, if you are within 5 miles of an airport there are additional rules that have to be followed.

Pilots occasionally do that with us. Rest assured, if you ever hear a pilot say that on frequency to a controller, all the controllers are making fun of them off frequency ? Conversely, we used that phraseology all the time in Civil Air Patrol when I was younger. Over (ksshhhhk).

Agreed.

There is no circulation so the heat can't exhaust. Heat is one of the largest enemies of radio performance and longevity.

There is little difference in performance between the Laird phantom and their 1/4 wave wire stub. Actually, the wire stub is less noticeable than a black or white phantom on say a red car.

For what it's worth, this is what the RR wiki has to say about it in two places: https://wiki.radioreference.com/index.php/Family_Radio_Service#Recognized_Channels https://wiki.radioreference.com/index.php/General_Mobile_Radio_Service#Recognized_Channel_Usage Beats me if there is actual general adoption of any of the above, as GMRS is typically just casual/local type comms for caravans and families in most situations, as many have pointed out. Interesting thread though!

We are peripheral to any IMS/ICS. They find and forward us work. I regularly call the local Emerg Mgt Agency for updates and info on the areas needing help. So, the answer is a little of both. We partner with a local church and send out volunteer work crews from the church. We provide the volunteers with tools, meals, showers, laundry and sleeping quarters at/in the church. We almost have the capability to setup in a parking lot and run alone, but that's not the best way to do it. As we are not officially part of the ICS, we don't get their comms. Plus, what we need is our own link to our work crews and our base and between "Black Shirts".

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Put up a UHF Yagi as high as possible and pointed in the direction of the closest repeater and/or base station. I use a yagi here in NW Indiana to reach several repeaters on the north side of Chicago (about 43 airline miles) reliably.

I can't stress this enough... Radio is not something to do (generally speaking). Radio is a tool you integrate into other aspects of your life to either make those other activities easier, more entertaining or safer. If you are buying a radio as a source of entertainment, you are likely going to be very disappointed unless you're a ham and can find people to chat with around the world. As far as picking a base or a mobile, there are some serious restraints for UHF (GMRS/FRS/70cm Ham/etc.). One is, its a line-of-sight application. If you don't have an antenna that is at least 50 feet higher than the terrain around you... your not talking very far. 100+ would be better. Trees, buildings, hills, etc all cause interference. At ground level, you will get to the horizon line, which is about 3 or 4 miles depending on how tall you are (and what's between you and the other station). As you get higher in elevation, the better your coverage will be. If you're mobile, you can drive to an area where you can get better performance. Some examples would be, at 1200 feet I got a solid 50 miles on GMRS mobile with 40 watts, mobile to mobile. At the same elevation I can also talk to a repeater in northern Virginia with an antenna at ~980 feet, while I am in central Pennsylvania with my 40 watt mobile. Same 40 watt GMRS mobile, but on the blind side of a commercial building, I experience high static mobile to mobile. Normally I can only talk about 2.5 to 5 miles car to car. Just some food for thought. I love GMRS and really enjoy having radio comms as part of my life. I wouldn't discourage anyone from getting into the hobby. You just need to be realistic about expectations.