2 meter radio in humv

[Kenneth Cole]

Hi
I have installed a 2 meter radio in my Humvee which has a soft top. My problem is with high SWR (over 3,0). Using RG213 around 20 ft. and have checked continuity and shorts. Antenna is a 5/8 wave firestix and is mounted on rear using military mount.
Any advice or ideas would be appreciated.

Ken

 

[Milcommoguy]

May not work right out of the box. May need to trim for proper match. Having it on the corner of fender it will have a distorted radiation pattern that is typical of location. Here's a link to help>

http://www.firestik.com/Catalog/2M-4.htm

Tune for maximum smoke white or black, CAMO

 

[Valor]

Do you have an antenna analyzer, mfj-259 or similar? That would help. Not sure if the firestik has a means to trim it to resonance. That military mount might not be the right one. You need a good ground plane for that antenna. Is there much 2 meter activity in Wyoming?

 

[nattieleather]

The link to the antenna site has a big yellow box that says the antenna needs a good ground plane. Since the HMMWV is aluminum body that might be causing some of the problem. Try running a grounding wire from the antenna mount on the body to the frame and make sure you use good star washers to connect it for good connectivity. The steel frame and motor may provide a better ground plane than the aluminum body is. That is what I would do if I was setting one up.

73, k8icu