>By NF0R

Before the "St. Louis Vertical" concept evolved my favorite field
antenna or wire antenna support for over a decade had been the "Portable
Random Wire Vertical". This is described in detail in the January 1995
issue of QQ. The design uses graduated aluminum antenna tubing (largest
1.25" dia.) available from Texas Towers and other vendors. Plan on
investing up to $75 in tubing, shipping and related hardware items.

The RWV is free standing and uses only one set of guys at the 6' level.
It is designed to be erected by one person. After a little practice this
amounts to an honest five to seven minutes. In the simplest form the
radiator is extended to 33.5' It is therefore a quarter-wave on 40M, a
half-wave on 20M or can be set to any convenient length required for a
match over 10-40M.

As a general rule I use a tuner and center feed with twinax. This makes
life in the field real easy but the RWV can also be coax fed and
optimized for a single band. For a ground system try three or more
folded radials as described in the original SLV article or W6MMA's mod
which employs rotor cable.

While not discussed in the QQ article, I routinely run the RWV at 42.5'
(a 5/8 wave on 20M) using the basic mechanical configuration. If your in
a hurry the same article describes how to feed the radiator as a
vertical random wire.

For overall operating convenience the SLV always gets the nod. But for
sheer performance potential (lots of vertically polarized aluminum high
in the sky) the RWV remains my antenna of choice.

The St. Louis QRP Society has used the RWV's tubing as an antenna
support for Field Day. With two extra guy sets it easily holds a
lightweight 80M doublet at 45'. The basic RWV nest to a little more than
6'. It will thread between front car seats or fit comfortably in the
bottom of a canoe. The radiator weighs six pounds plus a couple more
pounds for the outboard hardware. A few folks on the QRP-List have
already built and/or used an RWV including WU7F, W6EMT, W3RDF, KE0MC,
N0OCT, AG5P and WN9V.

I hope this information helps others enjoy QRP in the great outdoors
just a little bit more. Finally, there is absolutely no reason why the
RWV can't be installed in backyards or used on rooftops too. My
prototype RWV is attached to N0EVQ's chimney and I have given up any
hope of every getting it back! 

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