Get a Wilson 3' "No Ground Plane" Fiberglass antenna - called a "Slide and Tune" - Wilson's number: 305-430 for the kit which includes the antenna, 18' cable and mount. Drill 2 holes for the mount on the side of the cabover (+ a hole for the cable) - position it so the top of the antenna is about 12" above the roofline and the antenna is VERTICAL(important!). Run the cable wherever inside the cabover, etc. The cable CANNOT be shortened. This is a top-loaded antenna that does not need a "ground plane" I-E - metal under the antenna and it will perform very well without catching branches. A spring between the antenna and the mount is a good idea in case you do hit a branch.
The antenna SWR (standing wave ratio) stlll needs to be adjusted with a meter for best performance but the nice thing about this setup is that it can be adjusted from INSIDE the cab. Any radio shop can do that or practically any radio "Ham" (like me!) will have a meter.
Google on "Wilson Antennas" for all info and dealers.
2001 Dutchman Express 28A. I had mine installed by a local CB Shop. They ordered a bracket that screwed to the front fender right at the hood, up close to the windshield. Then they found and installed a very stiff antenna that would not flex and hit the cab-over. The radio is mounted to the drivers side of the engine cover and wired directly to the fuse panel. Coax cable is less then 10' long. Reception is excellent. The whole rig, including install was under $200. Took the guy an hour. Good Luck
'01 Dutchman Express 28A, Borg Chrome Dually Valve Stems, Pacific Dualies Wheel Simulators, '06 Tuscon, '06 FLHTC/I
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