New Cophased Setup

[DirtyDawgJake]

I managed to snap my factory antenna mount the other day on my truck (company 9400i) and since I have about a hundred bucks on my Pilot card I thought I might upgrade my setup. I'm thinking about going dual k40 truckers. My concerns with this are that I will be getting an xm antenna in the future and would need to mount it close to one of the k40s. Will this be a problem? Also was thinking on going with one of the 30 buck dual mount kits. Would this work good or should I spring for the clear belden (spelling?) coax and buy mounts separately? Do I need to buy a swr meter or will the one on my radio be sufficient? Radio is a Cobra bluetooth 29. I've also read different tuning techniques, one at a time and both together making equal adjustments on both, which is better? Also I don't need to worry about springs with whips right? These are my primary concerns and I'm probably forgetting something so any advice is welcome and appreciated.

[squirrellsgnwild]

with a whip antenna you will not need a spring. as for needing an external swr meter it would be best to use an external one. You could just find a competent tech and have them tune the antennas and you wont need to buy a meter.

[kd5drx]

Ok if you want to run a co phased set up first you need 2 like antennas. Then you mount the 2 as far apart as you can but at least 1/4 wave length which in the 27 mhz band is 102 inches or 8.5 ft the average length 2 truck mirrors are apart. Ok you get some one with an MFJ 269/259 or compatible antenna analyzer. you set each antenna separately so they they are set for best SWR then you run a co phase harness this is 2 pieces of 75 ohm coax that are cut to proper length and joined in the middle by a pl 259 to screw to the analyzer or the radio. Once you have the coax run you again put the analyzer on the system it should still be what it was when you set each antenna or some where close to it. If you need to change it you change both antennas the same amount. Now you can hook up the radio and go to talking and you have never keyed the mike or taken a Chance of burning up your radio. Be sure what ever antenna you run you get a good quality 75 ohm co phase harness it is very important to the over all operation of the system.

[DirtyDawgJake]

Well got it all hooked up yesterday. Went with the k40s and some premium mini 8. Man what a difference. My first radio check driver said it sounded like a million bucks, all I got in the past was that it sounded like junk. Anyways, thx for the advice and stay safe over there in Iraq kd.