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Old February 16th 14, 12:35 PM posted to rec.radio.amateur.antenna
[email protected] nm5k@wt.net is offline
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First recorded activity by RadioBanter: Jul 2006
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Default RV/Mobilehome RF gnd systems.

On Sunday, February 16, 2014 4:36:32 AM UTC-6, Brian Reay wrote:


What band or bands are you trying to work?




80m to 10m on this antenna, inc. 60m



I have antennas on the vehicle for VHF/UHF



--

73

Brian

G8OSN/W8OSN

www.g8osn.net


That makes it harder trying to do all bands.
It's often easier to pick only the bands one uses the most,
and compromise on the others.

In your case, I'd prefer string dipoles up between trees,
but it seems you lack the room for that.

My next choice would be mounting a mobile antenna on top
of the RV. You don't have to drive with it on, but if you
had an antenna mount on the roof to use, it would sure make
it easier to mount an antenna. You wouldn't have to worry
about a counterpoise, etc.. The RV would be it, assuming it
has a metal skin.
But I'd prefer using a normal coil loaded mobile antenna than
the auto tuned whip. I think the larger loading coil would
be more efficient, and better current distribution if center
loaded.

But I suppose you could improve the current distribution of
your 7m whip by adding some type of top hat, or top hat wires
or spokes.

The only drawback to a mobile antenna like say a bug catcher is
you have to be able to adjust the coil tap to change bands.
It may well be too high to reach on top of an RV.

So you'd probably have to yank it off the roof to change bands.
I have this on my mobile antennas, but I use a Hustler quick
disconnect, which makes it fast and easy.
I suppose a screwdriver antenna would be an easy route to
changing bands, but they are heavy and fairly expensive for
anything decent.

Myself, I camp a lot, and my usual setup 98% of the time
are 40 and 80 dipoles strung up in, or between trees.
Sometimes I run the two dipoles with one coax feed, sometimes
I make a single dipole, and use insulators with wire jumpers
to shorten a 80m dipole to 40m. Just depends what I have laying
around and how many trees are involved.
I don't worry about any of the higher bands. I can still use
them to a degree by using a tuner on the dipoles. Or tack on
an extra dipole if really needed. A 40 dipole works 15m as is
pretty well.
But I talk on 80 and 40 most of the time. 40 in the day, 80 at
night. And 160 if I have enough wire in the air.