Hi Ken: It is possible to put RF into almost any thing and make it act
as a radiator. I once used the windshield opening in my car as a slot
antenna on 10m. However, the setup you describe does not sound very
attractive as an antenna.
1. It is usually not good to have large capacitance between your antenna
and ground. The setup you describe sounds like it would be bad in that
respect.
2. Somewhere on the frame there would probably be fairly high voltage
and tape insulation would not do the job. If you raised the frame on
plastic spacers away from the truck bed it would be better.
3. It would be difficult to find a point on the frame where the R value
of its impedance would be 50 ohms and the reactance associated with that
point could be tuned out. It is possible to build a matching network for
50 ohms to almost any load impedance but in extreme cases it is very
lossy.
I believe the Hamstick in your available mount would run circles
around it. 73, Dan, N5AR
Ken Cechura wrote:
>
> Ok, last time I asked a mobile antenna question on a reflector, I got
> told to take it here. Hopefully someone has done something similar or
> can help.
>
> I want to install my HF rig in my truck. I already have a multitude of
> VHF equipment installed (scanner, V7A, APRS, and a CB). My truck has a
> tonneau cover. the soft kind with a metal frame. has anyone
> experimented with loading up such a cover for HF use? I know 80M might
> be a stretch, but ill bet I could get 10-20 on it. The metal frame IS
> insulated from the truck body via some foam tape on the edges.
>
> I have an antenna switch I was planning on using so that I can use the
> CB antenna mount with a hamstick or two, but was just doing some
> thinking over dinner tonight... thought it might be worth a shot.
> \
> thanks
> Ken
>
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