Home Forums Hunting & Shooting Canada Amateur Radio: Dualband antenna mount

This is a Comet NMO mount and a Tram 1480 dual band antenna. I bought two Tram 1480 antennas, new, for $5 at a garage sale about 15 years ago. The first survived bouncing around on my two Rangers. When I sold my 2008 Ranger and got the 2012 F150, I put it on that. It bounced around there for several years until, prophetically, an Asian (Chinese) tourist decided to drive his Audi into my truck last August. If this one doesn't work out, it owes me nothing. At $5 for the pair, I got my money out of the the first one, and then some.

Here are a couple of pix. The coax runs through a conveniently placed hole under the rear hatch. The only thing that I am concerned about is the location. The antenna is 34 inches. 12 inches of that is below the trunk line. 2m/440 mobiles only need to hit the repeaters that the operator needs. If this performs as well as its cousin, I'll be happy.

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Steve, ever hear that mounting an antenna in the centre of the roof, or trunk lid works better as a nondirectional antenna?

I've heard about CB.

You bet. My transmitted signal would be closer to omnidirectional if the antenna was in the centre of the roof. There are a couple of things that prevented me from drilling a hole however. The biggest wasn't cosmetic. I want to see what is under the headliner and keep the antenna away from the vehicle electronics.

Modern cars and trucks have a lot of electronics packed into a small space. I am unsure if there would be any interaction, so the best option was to put the antenna where it will cause the least harm.

The other thing is, this radio is an FM transceiver. The signal has to reach a rebroadcasting station (repeater) so that my signal can be boosted and rebroadcast.

Unlike ssb or AM, one only needs enough power to reach the repeater and not bring in any noise. This is referred to as "full quieting".

Most FM transmitters have several power levels. I have never needed more than 25 watts out, even though my radios have a 50 watts max. output capability.

So, where I live at least, as long as I can hit the repeater at full quieting, the antenna radiation doesn't need to be the most efficient.

My apologies for the long winded response.