I am running an 817 and I'd like to go out portabel with this rig.

I am planning to buy an Outbacker on a tripod, using a handmade metal
mount with the possibility to attach a counterpoise.

Will the Outbacker work in this setup? Or does it need a lot of metal
like cars habe?

I would use a counterpoise of course.

Any hints or suggestions?

An Outbacker can probably be made to work in this way, but I don't
think it will work _well_. One of the local ham-clubs I belong to
recently had a presentation from a guy who has been trying to work
portable with a rather similar setup (a multiband mobile vertical, on
a tripod, with counterpoise wires, and an FT817) - he sums up his
results as "I can hear them OK, but nobody can hear me."

An Outbacker's efficiency is only a few percent - there are a lot of
losses inherent in its design. Some people have referred to antennas
of this type as a "tuned, lossy counterpoise, connected to a large
untuned radiator known as a `car body'".

Since you're going to be running only a few watts of power, I think
the Outbacker's rather low radiation efficiency is going to be rather
frustrating for you. An Outbacker mounted up high on a Ford Aerostar,
and fed with 50 watts PEP, gives me "Good mobile signal" reports from
across the Western U.S. on 40 meters... but fed with a few watts from
an FT817, with only a minimal counterpoise located fairly close to the
earth's surface, and I think you may have trouble being heard well.

For less weight and far less cost than an Outbacker plus tripod plus
counterpoise, you could carry a "yo-yo" adjustable-length wire dipole
plus coaxial feedline plus a Norcal BLT or similar lightweight tuner.
String this up from a couple of convenient trees, and you'll get an
order of magnitude more signal out - probably 1-2 S-units more.

For other options, see http://www.amqrp.org/projects/projects.html -
take a look at the "Crappie Antenna" and the "St. Louis Vertical" -
two interesting ways of using a very-lightweight collapsing fishing
pole as an antenna support.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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