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Yes. Put very simply, no antenna has any gain as they are passive devices, they simply radiate. True gain requires amplification. What is called gain in an antenna is really apparent gain. That is, the the strength of the received signal, either at or from the remote radio is compared to the signal received using an hypothetical lossless antenna that radiates or receives signals equal from all directions - above, below and from the sides. If an antenna's design favors signals transmitted or received from some particular direction, or directions, then at the same time it is reducing the signal transmitted or received from some other direction. The result of changing the radiation/reception pattern results in signals from/to some direction(s) being stronger than from others. Thus the apparent gain. Your doughnut radiation pattern favors signals from/to the sides and reduces signals sent/received vertical. It is a little bit like adding a lens to a lamp. A bare bulb (theoretically) radiates light in all directions. But, by placing a reflector behind the bulb and a lens in from of the bulb to direct the light, you will have much more brightness in the direction the lens faces, and much less light behind the reflector. But, the actual light output from the bulb remains unchanged. In fact, Yagi design directional antennas use elements with those exact names: directors and reflectors.

Thanks berkinet. Yes I did mean PL-259 connector. Sorry, typing to fast for my brain. So, looking at your table, at 15 ft of RG-58 my loss should be 1.68 db. Which sounds very acceptable. I guess the key for this application is, keep line as short as possible and minimize/eliminate connectors. Thanks again.

That antenna along with many others on the market, reminds me of something I heard about fishing lures: they're designed not so much to catch fish, but to catch fishermen. Generally speaking, the shorter the antenna and the wider its bandwidth, the less gain it has. A better way to state it is the more loss it has.

I actually run both on my F150. The only benefit of the 4503 is size. It works well on my local trunking systems but no antenna will work there. For GMRS its ok when on some repeaters, but simplex is junk. I since have put the 1/4 wave back on my GMRS mobile and am very happy with it.

Okay, I'm hooked. I was walking out to our local crop share pickup today when a neighbor texted me and asked if I knew what the huge plume of smoke is rising from near Alexandria, Virginia. Nothing (yet) on the news. I had my radio with me because I was doing a couple of antenna/signal tests anyway, so I hopped on the local repeater and asked for anyone nearby to provide a visual situation report. Within a minute, I had 3 separate responses. Turned out to be a huge construction fire, now at 5 alarms. The local news story hit their web site and alert system > 30 minutes later. (See https://wtop.com/fairfax-county/2020/02/massive-fire-engulfs-fairfax-county-construction-site/) No big deal, I suppose, but I will add that from my vantage point, the smoke was along the glide path into DCA (Reagan National) airport. I'm the son of a retired 747 pilot (and fighter/aerobatics RAF team), so big plumes of smoke near airports have always made me uneasy, since long before 9-11. Anyway, LOVE my GMRS comms now that I've learned about the world of repeaters out there. I'll be taking my Ham technician class exam in a couple weeks as well. I'm hooked. Cheers, Ken (WRFC318)

not to rain on this idea, as i think it's a good one. i WILL give midland a little credit, though, as they DO actually have an article on the licensing topic (and include "license required" in the product descriptions, at least for the micromobiles, though you have to "read more" to see it), and reasons to get licensed. as you said, though, their primary focus is selling product, so it isn't particularly easy for the average person to find. i did a lot of digging and reading before i pulled the trigger on radios, and stumbled across it. https://midlandusa.com/why-do-i-need-a-gmrs-license-how-do-i-get-it/ i definitely think there's still room to expand on the topic, and make the information a lot more accessible than they have (get it more up-front), also know it's a balance being careful not to "borrow" or end up too similar to theirs. this site (and forum) are one of the places i did a lot of reading before jumping in. on the main thread topic, though, one small idea that comes to mind...maybe i missed it, but i didn't see an actual designated spot for "(New) Member Intros", just a few scattered in the general discussion and the private discussion areas.

Your best bet is to use the coax that comes preinstalled on the NMO mount. This cuts out SWR issues caused by poor solder jobs and takes less time at that point. With such a short run you shouldn't have much loss. I can tell ya upfront installing anything the size of LMR400 in a vehicle, then attempting to attach it to an NMO connection and your just asking for a troublesome install. (LMR400 doesn't flex easily and is quite thick, about 1/2 inch.)

V1 and V2 firmware ARE NOT INTERCHANGEABLE. This is because of minor hardware differences inside of the radio as well as some features the V2 radio has that the V1 radio doesn't. Overall these features aren't really used in GMRS and are more towards commercial radio For example enhanced fleetsync functionality and the available use of some MDT hardware. I have several TK880's both V1 and V2. V1 radios I used to build a small portable repeater that I can set up anywhere, even in a campground. The V2 radios are installed in our vehicles and while we use fleetsync for radio ID and text messaging on my local repeater, there isnt much use for it when I go onto another system. This is because the Fleetsync codes we use may be different to other users. Anyways, If the offer is right, $20-30 for just a radio, or maybe $50 for radio and mic in fair condition, go for it, Anything more and you could likely do better on Ebay.

"...Just wasn't sure if using smaller diameter cable would have an effect on the radio performance per some of the discussion I read about." The small cable to stay away from is RG-174u and its equivalents. That is the small stuff you find as the stock cable on the Midland Micro-Mobile antennas. Most NMO mounts come with preinstalled RG-58u, which is slightly smaller in diameter than a #2 pencil. RG-174u is about the diameter of the ink tube inside of a Bic pen.

I laughed so loud I woke my wife up. A friend of mine was going to put one on his Range Rover. I told him to just give me the $10 and sell his radio, because the end result would be the same, only I will at least be able to get a cheeseburger and a coke. LOL

There is a reason we are suppose to clear the air for emergency traffic. Sometimes the phones go down, or the battery dies, or we leave them home. Such an incident happened to a family member on her way to work. A vehicle had taken out a pole, continued on into a fenced off area containing a cell tower destroyed a trailer that was in there. The cell tower went down and all cell coverage dropped. Having seen all this, and being an emt, she called by radio and gave me what info she had and her location, I then relayed the info through to the PD using a neighbors phone (We use cell phones so no landline in the house.) Officers were dispatched and driver was charged with DUI. Turns out the trailer was running as a temporary controller until a part could be replaced in the little brick hut next to the tower. When the car struck the trailer it damaged the coax jumper going to the tower and the equipment inside. When it went down the next closest tower was about 5 miles out with heavy pine forests and hills in-between them.

BTW, I honestly don't understand why you just don't go with a simple 1/4 wave NMO mount antenna. They are dirt cheap, and easily replaced. A fiberglass antenna, no matter how rugged, will shatter if it hits a low hanging branch, overhead rocks, or even the ground (for flipper). A simple metal 1/4 wave will just bend over and can be straightened out in seconds (or replaced with a spare).

You have mentioned the suitability of an antenna for repeaters and simplex as though the two things are inherently different. Well, to some (very tiny) extent they are, in that with a repeater your transmit and receive frequencies are 5mHz apart, so there is a small degree to which an antenna might be tuned differently depending on whether the main use was simplex (tuned right on frequency) or duplex (somewhere between the Tx and Rx). But, that is really pretty insignificant. On the other hand, an antenna's radiation pattern can make a difference depending on the physical relationship between two stations talking simplex, or a station talking to a repeater. But, since many repeaters are actually located pretty close to the ground, like on roof tops, and two stations on a jeep trail could be several hundred vertical feet apart, you can't really say any particular "gain" pattern is better for one or another. However, as others have noted, a simple 1/4 wave may well be the best compromise, especially in a situation where both stations are in motion.

I'm open to guest authors who want to help out with articles like that. Articles in general are one thing I want to add that has been missing. The site is functional for looking up repeaters, but lacking in substantive content that will drive traffic to us.

Alan, Just an FYI. I just went through exactly what you're doing. I ended up with a Kenwood TK-880-1 V2 @ 25w from used-radios. You can do some searching on this forum for the benefits (or not) of 40w over 25 (draws 12A vs 8A on TX, is 1" deeper). I'm still considering the 880H for my pickup with more room to mount and dual battery reserve (not that I intend to TX from the SxS for long w/o it running). Installed mine in a 2019 Yamaha Wolverine X4. I think I'm going to like it. Got a couple HT as well to hand out to family when on the trail. Lots of help here and I've covered a lot of the questions you might have. You can search my posts for the answers I got on the topic. Or chime in with me and I'll do what I can.

Alan; go for it....It is best option as it will do wideband mode as GMRS permits. The Midlands and cheaper radios don't.

Yes, the mic can control all of those and more, the down side is you need to have a "function" button. Now if you get the kit from Kenwood, the function button could be a foot petal, if not it is a button on the face of the radio (A/B/C/D) Thus it isn't really handy to use the mic for those functions. It is handy if, lets say a repeater has selective calling, you can set A to function, then use 0-9 on the keypad of the mic to set up your auto-dial. Basically it allows you to add more functions to the radio with only having 4 buttons on the face plate. For my set-up, I programed the buttons as follows: Scan: Scan Mon: Monitor Vol: Volume up/down Group: Ch up/down A: OST [for changing between 15 PL/DPL tones] B: Memory (RCL) for paging a particular radio or group using DTMF C/D: Group up/down [switches between my home repeater, all repeater channels, and simplex frequencies] Foot: N/a [i don't have one] I find this set-up works for my needs, your needs may be different. For instance you may not use radio paging when looking for a particular user or group so you may change "B" to something like Scan add/del. Perhaps you dont need the MON button so you may set that to key lock. Its completely customisable.