any advantage running two antennas?

The advantage might be to kill a dead spot because of the cab. As for how long the longer the better however you have a height limit so you would have to know how high the mount is and go from there.

 

Using 2 antennae gives you better propagation (range) along a line that is perpindicular to the line between the 2 antennae. On an omnidirectconal signal-strength chart, the TX/RX pattern looks like a 'figure 8'. The best direction for communication will be directly in front of- and behind- your truck.

The 2 antennae must be electrically identical. Best propagation if they are 1/4 wavelength (use the freq for chan 19/20). Just get 2 of the same antennae. Adjust both antennae length for the lowest overall SWR. Under 2 is good - over 4 is real bad. 1.1 is fantastic.

KJ6RGV

Sent from my DROID X2 using Tapatalk

 

When I was driving a Columbia, my set up was a Cobra 29 Classic with the dual Radio Shack 4 ft. fiberglass antennas with the co-phase coax that came with the antennas. I pull pup vans. I used the factory mirror mounts. It was near perfect SWR and the range was very satisfactory for a legal radio. 2-4 miles average range. Now I run a 2010 Cascadia, and use the factory stock antennas/coax, and it actually works about as good. I tried a 5 1/2 ft. Francis, and a Skip shooter mounted on the rear of the cab near the center and it was a little better, but not worth the trouble.

 

As long as you don't pinch it so bad that it breaks the shield and/or the conductor and make them short out on each other, it should be OK.

 

If you decide you need more range, try a 5 1/2 ft. Francis fiberglass. It worked better than the skipshooter and as good as a monkey made. They are pre tuned for the Cobra 29. I ran my coax through the door jam on my Columbia for 4 years with no problems.

 

Not trying to be picky here, but you don't tune an antenna to a radio, you tune it to the vehicle it is mounted on. The radio doesn't have a thing to do with it.

 

YEP it works like this ..... you tune the antenna so that it looks like about a 50 ohm load at one end of the 50 ohm coax and and you will make your radio a happy camper ....

 

I want one of those MJF antenna analyzers really bad! I can't justify the expense, but have just always wished I had one........ To those who don't know, you don't need a radio to tune an antenna to a vehicle if you have one.

10-4 on the 50 ohm, too bad that ideal is almost impossible to attain on a mobile setup. Everything is a compromise when it comes to mobiles, especially antenna length................going to bed....good night/morning!