I've recently gone from a single Wilson mag mount to duel 2 foot Firestiks. Now I can't here anyone. The Firestiks have little adjustments under the end caps which I used to set the SWR, but I could only get it down to 1.5 on thr right and 2.0 on the left. The brackets are mounted to the mirrors which are plastic. I had to cut the coax to feed the wire into the vehicle neatly. I stripped the ends and just tapped them back together keeping the center wire separate from the outer shied. The coax that I used was a 6 footer left and right. Where have I gone wrong?
Duel 2' Firestik reception problems
Discussion in 'CB Radio Forum' started by renonation, Apr 8, 2008.
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First thing you did wrong was go to twin 2 ft antennas they are way to short and are only a compromise at best. The second thing is you cut the coax NEVER NEVER NEVER cut and tape coax. Third thing you are using the wrong length of coax. You need a phasing harness to run 2 antennas. This consist of 18 ft of rg 59 75 ohm coax with a single PL259 on the radio end and then what ever type of connection on the other to connect to the antennas. The mounts on the antennas should be grounded and you never check SWR on one antenna at a time on a co phase antenna set up you can take one antenna off and check it solo and then take the other and swap them out that way and then go back and check them together and adjust them together at that time. That should get you in the ball park and i wish you luck
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kd5drx is right, ill just rephrase it though, in a little more detail.
first off you should have co-phased coax 18' (which is 18' both ways) not a splitter you need to run that stuff to the antennas and check the SWR inbetween your co phased cable and the radio with a short jumper coax cable. If you ever need to cut coax you cant tape it back together this could be your biggest problem. if you dont know anything about cutting, coax stripping it and soldering on a new end radio shack has pl259 coax connectors that are solderless, you slide it over the end you cut and tighten a screw and your done. When you check the SWR set both antennas all the way down. then check the swr, if you need to adjust both of them by the same increment until you get your swr how you want it. only problem being you have short antennas that may not adjust to well.
Plastic Mirrors are probably also a problem, you need a ground,
i dont know if firestick fiberglass antennas come with a ground wire, i know wilsons do, you jsut need to run that cable to something grounded on the vehicle. Best shot if it doesnt have it runa a ground cable (some wire) from the mount to somewhere you know is grounded)
now you asked where you went wrong, it was just about all of it, b ut when you start correcting, every little bit will help, but go throguh the entire check list to get the best set up you can with what you have. dont stop cuz you see an improvment. -
The shorter the antenna the harder it is to tune.
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Thanks guys. I had 2 foot antennas on my Chevy S10 which had metal mirrors about 15 years ago but a technician installed the set. I remember that he cut and soldered the connections and it was to exact length. Just wondering where the hell would I coil up all that coax? I might as well see if though guys are still in business. Talk about a fine science to these things, not like sticking a mag mount on the roof and away you go.
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i run a single Monkey Made..05 swr,best dam antenna i evar had
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what you can do with all that extra coil is coil it in loops with a larger diameter that 12" and put it under your seat. or seats since your going dual, just dont make the coils any less than a foot in diameter. (the bigger the loop the better)
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The responses from the various members of this board to your dual antenna problems are excellent.
You might consider why you really want dual antennas. Performance wise a good single antenna will usually work well. However, if you are going for a "cool" look I understand that too.
Back in the Day this "hip" fellow came to our CB Shop looking to have two 6 foot Firesticks installed to bumper extenders on the left and right of his rear bumper.
We pleaded with him to not bother with co-phasing antennas on a Trans-Am (or was it a Camero). However, he just had to have two antennas for a "look." I mentioned the co-phase harness, the tuning difficulties and such. We compromised by connecting only one of the two antennas to the radio and just made the second one a parasitic dummy antenna. This worked just fine and, man, I never had a happier customer when he saw those two antennas coming off his rear bumper. He said something like "Yeeeeeeaaaahhhh maaaaan..." I truly miss customers like that.
Good luck with your install.
John -
thats the same thing i did on my pickup, i have two four foot freightliner antenas but only hooked up one to make it easier. i see people all the time with just one 4 foot on one side of the box and think it looks really stupid, so i just have the other one mounted there so it looks better, if you are going to do this, make sure its the passenger side that you hook up. passenger side will get better reception. at first i had them hooked up to the plastic tool box, but i needed a ground, so when i took the tool box out a little while ago, i mounted them right to the box itself, that is just temperary though untill i get a back rack for it.
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im surprised one antenna will work for you guys.... when i tried that my reception was horrible, even with my swr tuned down to 1.2 to 1.5 just because of the ground plane....
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