Question about CB antennas

[SilveradoGuy85]

I've had a CB in my truck for years and always had either 1 antenna or 2 of the same length. Right now I have (2) 4' antennas I got from a truck stop. I was just wondering if it would work if I keep one that's 4' and replace the other one with a 102". I'm thinking that it will be hard to tune them, but just wanted to ask in case anybody knows if it's worth it or just a waste.

Thanks

 

[great white]

Drop the 4', run good coax and go with a the 102.

Nothing gets out better than a 102 steel whip.

The 4 footer actually is also a 102, but it is copper wire wound around a fiberglass core. Every cb antenna is a 102 because its the wave length for 27 MHz. Shorter or longer is out of range. But when you wind it into a tighter and tighter coil as the whip gets shorter it becomes a less efficient radiator.

Twin whips on a pickup truck are essentially for looks only. They are supposed to make the antenn stronger in the front/rear direction, but you need a minimum of 8 feet of separation between the two and and effective "ground plane". This is not possible on a pickup truck.

Twin whips for looks are better set up with one active and one dummy. Then, if you break one you can just swap your coax over....

 

[SilveradoGuy85]

Drop the 4', run good coax and go with a the 102.

Nothing gets out better than a 102 steel whip.

The 4 footer actually is also a 102, but it is copper wire wound around a fiberglass core. Every cb antenna is a 102 because its the wave length for 27 MHz. Shorter or longer is out of range. But when you wind it into a tighter and tighter coil as the whip gets shorter it becomes a less efficient radiator.

Twin whips on a pickup truck are essentially for looks only. They are supposed to make the antenn stronger in the front/rear direction, but you need a minimum of 8 feet of separation between the two and and effective "ground plane". This is not possible on a pickup truck.

Twin whips for looks are better set up with one active and one dummy. Then, if you break one you can just swap your coax over....

Thanks. I used to have a 102" and it worked great. The reason I usually run 2 fiberglass antennas is because I figure if it works for semis then it should be ok. I know that the antennas aren't as high of course. Also the reason I don't have a 102" anymore is because I had one of the cheap $20 Radioshack antennas and it snapped right at where it screws into the mount.

I guess (2) 102" antennas would be major overkill lol. But, you didn't answer the main question, how would it do with (1) 4' and (1) 102" antenna.

 

[great white]

Thanks. I used to have a 102" and it worked great. The reason I usually run 2 fiberglass antennas is because I figure if it works for semis then it should be ok. I know that the antennas aren't as high of course. Also the reason I don't have a 102" anymore is because I had one of the cheap $20 Radioshack antennas and it snapped right at where it screws into the mount.

I guess (2) 102" antennas would be major overkill lol. But, you didn't answer the main question, how would it do with (1) 4' and (1) 102" antenna.

I wouldn't.



Co phasing doesn't work on semis either.

I've set up a couple rigs for a couple guys I know and here is what we did (after I explained the antenna theory behind it to them):

Twin top load Wilson's. I like silver loads. One antenna is active, the other is a "dummy". When they snap one off on a sign or other overhead obstruction, they swap the coax to the one that survives. We run the the drivers side active since it makes a stronger signal to the front left. The passenger side usually is the first to go anyways since trees and such tend to be on the pasensger side. Only thing to worry about on the drivers side is big signs hanging over the highway. In town its a crap shoot as to which one goes first.

I use four footers on rigs and I have a single 5 on my pickup. Wjenim base camp, I runs single 5 footer in a drill through mount center of the cab roof. When I move I swap the coax to the rear 5 footer and remove the roof one or I screw a 3 or 4 footer in the roof mount.

Even one I know that I've worked on is very happy with 'em.

Most run "heat in the wire" too. one guy has one helluva footwarmer in his. Thats why I like the Wilson silverloads, about the best fiberglass ones I've found.

Still, nothing beats a 102 steel. Look up some cb keydown completions on YouTube, you won't see one fiberglass, they're all 102's......