Ham Antenna w/Limb Risers?

[adventureduo]

Getting ready to outfit the 80 series with a HAM radio.

Anything one needs to worry about running a HAM hood/fender mount with limb risers?

I would think this would cause all sorts of trouble. Am i correct?

 

[articulate]

Hmm, mewondered about this too. If the limb risers are metal cable and your antenna hits one, I figure that can mess with your out-going signal.

Just a suspicion.

 

[Pskhaat]

Yeah, I'd consdier using a lip mount on the back on the lift gate, get it nice and high. But then again, you've got a pretty non-trivial roof rack. Have you considered mounting it there? You can always do what I did and mount it on your ARB bar, but that's a pretty poor place for it in reality.

 

[DaveInDenver]

Getting ready to outfit the 80 series with a HAM radio.

Anything one needs to worry about running a HAM hood/fender mount with limb risers?

I would think this would cause all sorts of trouble. Am i correct?

I think you already know the answer, do not let the whip hit the limb risers if they are grounded. Much easier said than done, but I'm picturing nylon washers or something isolating the risers at the bull bar and roof rack. As long as the wires are not grounded, then you probably won't harm your radio's final outputs. Even if they are isolated from ground, depending on how close they are, they could act as antenna elements (called parasitic elements, basically you'll be making sort of a Yagi), so it's possible they could still be a problem if they mess with the directivity of your antenna. But for that they would have to be pretty close.

 

[adventureduo]

I figured it will do something... just what .. i didn't know. The limb risers that i have are covered by a plastic housing. Does this matter? I have thought about the hatch mount and that is a possibility..including mounting it on my roof rack too. Any min length you should keep your HAM antenna away from CB? My Wilson is already up on the rack.

 

[Pskhaat]

As far away as possible, but I would think two feet or so would be realistic.

 

[adventureduo]

How bad was your radio when you mounted the antenna on your bumper? I really dont feel like bringing ANOTHER piece of coax through my roof line...

 

[Pskhaat]

It's suprisingly OK. I have an acceptable SWR, and get decent performance. Now, I know I can get more because when I move my radio into my commuter car with a basic trunk lip mount, I get much better reception and distance.

It's acceptable, but certainly not optimal.

 

[gary in ohio]

Well first what band/frequency? you talking about. HF, UHF/VHF?

I wouldnt want the the risers to come in contact with any antenna. You have lots of roof and rear door mounting space for an antenna also.

 

[lysol]

An old one, but the question still remains.

 

[Shawn686]

Buy the vinyl covered cable for the limb riser = no problem

Shawn

 

[Chris Boyd]

Why not make the limb risers *the* antenna. VHF on the right and HF on the left

 

[Tennmogger]

With the plastic cover on your risers I would not worry too much about the radio or antenna. The antenna could pass less than an inch from the non-vertical riser and the capacitive coupling would still be minimal. Dave already explained the problem if the riser is resonant on the transmit frequency.

I run a CB antenna about 2 feet from a 2 meter antenna (both are base loaded mag mounts) and no damage after years of use. I just don't transmit on one when the other is turned on because the other one might make funny noises and create feedback.

Bob WB4ETT

I figured it will do something... just what .. i didn't know. The limb risers that i have are covered by a plastic housing. Does this matter? I have thought about the hatch mount and that is a possibility..including mounting it on my roof rack too. Any min length you should keep your HAM antenna away from CB? My Wilson is already up on the rack.

 

[Prybry]

You could also put a piece of shrink tubing on the antenna where it might contact the risers... the vinyl covered riser cable is also a great idea..
As long as the antenna isn't grounded during transmit you are fine...

 

[1911]

Why not make the limb risers *the* antenna. VHF on the right and HF on the left

The HF one would one looooong limb riser!