Predator antenna questions please help

[sancho]

Anyone out there know if I can run a predator dual coil antenna and swap out the lower shaft with the 22 or 27" shaft?

I will be mounting on centerline just aft of the cab atop the bed rail. Just trying to get the coil above the cab without the overall length being 35' lol

[sonoma]

I would just build a mount out of tubing to get it higher up and that way you can use about any antenna you want.
jessejamesdallas has a picture posted with his done that way on one of the forums. his looks nice.

[sancho]

Yea I mean I could build a mount but I see the predator dual coil but it's not offered in a 27" shaft but wanting to know if it's possible to swap it out and if it will work

[jessejamesdallas]

It will work, but the problem is going to be the shaft itself will still be lower than the roof, and since the shaft IS PART OF THE ANTENNA, it may not tune very good since 27" of the antenna (the shaft) is behind the cab, and lower than the roof. It would be better to build a riser for the antenna to get it roof level...

I first tried a 27" shaft on my Tacoma, mounted to the top of the bed rail right behind the cab, but could never get it tuned like I wanted, so I built a riser out of some 1" square metal tubing from Home Depot to get the antenna's mount even with the roof line...This worked out just fine.

Here's a pic, with a 12" lower shaft Monkey Made "Big John" antenna...originally I had one of my Predator 10K's with a 17" shaft on, but went with the Monkey Made just because I liked the looks of the over-sized coil on my little Tacoma.

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On mine, the riser go's all the way to the bed floor and is mounted between the front of the bed and the tool box. I made a L bracket out of a piece of angle iron to mount it to the floor, and another L bracket is bolted to the top of the 1" square tube for the antenna mount...Ground straps are also attached to the bolts holding the thing to the floor and go to the frame under the truck for a better ground...Also, I drilled holes in the tubing to run the coax up to the antenna mount so it's hid and doesn't flap in the wind...

-- August 13 2016, 18:54 PM --

Yea I mean I could build a mount but I see the predator dual coil but it's not offered in a 27" shaft but wanting to know if it's possible to swap it out and if it will work

Reason it's not offered with a 22" or 27" shaft is because it makes the antenna too top-heavy...with two coils the antenna is going to have allot more wind drag which puts stress on the bottom part of the shaft where it connects to the antenna mount. This is the weakest part of the antenna, and is where most shafts will break. (This one was mounted on the roof of my Suburban, and got broke from hitting a tree limb...just wanted to point out where they tend to snap)
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[sancho]

I definitely appriciate all the information on this. I'm thinking I'm going to try it and see what happens. If it doesn't tune the way I want I can always buy another shaft, stinger and try another mounting location
I'm a beginner so I'm learning a little here. How do you suppose the set up will work with an all stock Grant xl (Philippines)?

[sonoma]

a grant XL is a good radio but if your antenna is not placed right it will not perform well. swr needs to be below 2.0 for good TX and RX.

[drdx]

Regardless of the antenna type, anything in the 35 inch range is going to be limiting the a efficiency a ton. But, experimentation is what it is all about. Let us know how it turns out. If you were ever going to attempt efficiency at that height range then this style is the way to go.

-drdx

[sancho]

Well I'm trying to stay around the 5' range so I figure this would be the way to go.. my only concern is the antenna breaking off at the base due to the longer shaft

-- Friday, 19 August 2016, 21:14 PM --

Ok guys my antenna came in and I'm trying to swap out the 12" shaft to the 27" shaft but I can't seam to break the lower shaft loose. I really don't want to damage it before I can test it lol.. any suggestions on getting the lower shaft to break loose at the threaded joint?