I have a mount on the top of a Tacoma truck i have recently bought, It is a threaded mount with a cap to cover it, looks like the antenna was to be used when needed and then be removed when not. I have been trying to find out what kind of antenna fits this mount. Is there an easy weay to figure this out? Im kinda dumb on the radio stuff (CB im just assuming) but i was wondering what fits the mount. The threads are about the diameter of a quarter and fairly short, enough for an antenna and there is no hole in it like somthing to screw down into it, looks like just a flat contact point.
I could take a picture of it but i dont know how the this group feels about them, some dont want them.
By the way, NMO stands for New MOtorola, a base design for mobile antennas that was designed specifically for hole installations. They can be installed from the top (outside) and are water proof.
That stands for "new"?? Is this fairly new? It does appear to be what it is. I hope i dont sound like a dummy but what is it generally used for? I saw the industrial type reference, but what other items could this be hooked up to? CB maybe, would it work? Why would you want an antenna like that if most cell phones today dont use external antennas?
Normal CB antenna mounts are about a 1/2" to 5/8" thread. They're called SO-239. The mating plug is PL-259. I can understand the SO standing for socket and PL standing for plug, but why the different numbers??? :>))
As for the NMO, there are Ham radio antennas that use that configuration as well as commercial (fire, police, emergency services, business-band, etc.), cellular phone, and CB antennas.
I guess what im having trouble understanding is... i have the mount, can i use that with a matching antenna for a CB? I mean the antennas that mount to the NMO will they work? Is this a dumb qustion or am i missing somthing?
The only dumb questions are the ones you do not ask. Never be afraid to learn - it can keep you out of trouble.
"New Motorola" in this case being from the 1960s and '70s when VHF (150 Mhz) UHF (450 Mhz) and Cellular (800 - 900 Mhz) two-way radios were taking off, and the older ball-mount designs wouldn't work. And since Motorola engineered the original design, they get their name slapped on the new "standard".
The NMO mount is a good design because it has a large clamping area to the car roof to keep the antenna mount from pulling out if you hit a branch. There's a large O-ring to seal it to the roof, and it tightens easily with a two-pin spanner or a big adjustable end wrench.
They make several CB antennas that fit, I have a Larsen NMO-27 antenna for my car. Here's one place you can see them -
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They still make "Car Kits" where you plug a handheld cellular phone into a permanent antenna and power booster in your car, but they're rarer than hens teeth because they're expensive. And every time you get a new phone, you have to get a new car kit too. Only needed in fringe areas, and then you'd want one with a power booster built in.
You can also use an NMO mount for a scanner receiver antenna.
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is a niceone, there are others. When I sell my vehicles, I leave the mounts and put on caps just like you found. The nice thing about the NMO is it works for lots of different frequencies, so a mount that's useless now may not be later.
Your Tacoma was most likely previously used as a part of a commercial fleet. That mount is normally used for an antenna about the size of a cellular antenna, but would be used for a commercial trunked VHF system up on 900mhz. The Teletrac Commercial Vehicle Location System also uses this same antenna. If you remove the short "coily" antenna from the roof of a police car you'll see the same mount.... right before you get to see the inside of the car :) There aren't enough threads or strength in the mount for a CB antenna. You might be able to find or make a black plastic dome cap to make it look a little more finished, but unless you're willing to do some bodywork or want to put an XM antenna in the same hole, it's there to stay.
"N" for "new" as in within the last 20-30 years or so.
Not dumb at all, and the NMO mount can look like there's something missing, but the proper antenna will screw on and make a good electrical connection and a waterproof seal.
Not to sound sarcastic, because I'm not, but NMO is NMO. Whether the original system was used for CB, Ham, cell phone, or business radio, you can mount any NMO base antenna to what you have, just screw it on. With today's radio designs, a two-way radio could have been mounted under or behind a seat, or under the dash, so you will have to search for the end of the coaxial cable that comes from the NMO mount.
If you do a Google.com search on NMO +CB, you will come up with many companies that carry CB radio mobile antennas with NMO mounts. All you have to do is purchase the antenna and screw it on your existing mount. It shouldn't require anything extra. It's kind of like buying a garden hose, in the U.S., all garden hoses have to have the same connection or they wouldn't fit the standard faucet. All you have to do is buy an antenna with an NMO connection and it will fit.
One last thing, if the NMO base (the part mounted on the truck) has been exposed to the elements for a while, it might be a good idea to take a pencil eraser and lightly "polish" the center connector "button." This isn't absolutely necessary, from what I hear, but I just like things to be nice and shiny when I make a connection. Also, use a cloth or paper towel to clean the area between the center button and the threaded portion to make sure there's no moisture or dirt present.
I don't mean to get so "wordy" in my replies... :>))
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