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eHam Forums => Mobile Ham => Topic started by: PUBLICGUARDIAN on September 01, 2005, 09:45:56 PM



Title: Yaesu 7800 rig in RV-Antenna mounting
Post by: PUBLICGUARDIAN on September 01, 2005, 09:45:56 PM
I have a class "c" RV. That has cab over a van front body. It has a ladder in the back. What are options for mounting 2 band antenna. It seems to me it is easiest on the side mirror arm and run the cable through the door but I think performance would be poor.It has been suggested to put the antenna on the ladder. But that is a long cable run and how do I get the cable into the cab. I really don't want to drill holes if I can help it. Also where do you tap power from? I take it the power socket is not rated for the power the rig wil draw. Thanks WD6DSG


Title: Yaesu 7800 rig in RV-Antenna mounting
Post by: KB1LKR on September 01, 2005, 11:31:20 PM
Ideally you'd get your power direct from the battery terminals via fused (at the battery) large gauge cables, and bring them thru the firewall either at an existing opening or by drilling, grommeting and sealing another -- shouldn't be too hard to find a spot  on a cutvan chassis as you can remove the engine cover and look around a bit more than on most vehicles.

Not sure what to suggest for antenna mount other than an NMO drilled into the roof w/ a short whip. Is it mettalic of plastic roof shell? If plastic one gets into ground plane issues if 1/2 wave whips are not used.


Title: Yaesu 7800 rig in RV-Antenna mounting
Post by: K0BG on September 02, 2005, 06:46:48 AM
Steve gave you ideal advise. However, let me emphasize a couple of points.

First, never use existing vehicle wiring to power any amateur radio equipment. If for no other reason than to minimize RFI problem, ingress and egress.

Mounting a 2 meter antenna "CB" style on a mirror mount is a prescription for poor performance and possible RFI problems with respect to inadequate groundplane issues.

If height is a problem, you'll find that an ordinary 1/4 whip mounted atop your motor home (if it is aluminum) will perform beyond expectations. If it is fiberglass, I suggest you use an antenna designed for that purpose. www.radialllarsen.com is a good place to start.

Alan, KØBG
www.k0bg.com