[FoxHunt] Turnstile antennas for 2M

[Marvin Johnston]

Horizontal polarization has been used for years on 2M ARDF hunts over in
Europe. From the people I've talked to, there are several reasons that
include less effect from the vertical attenuators out on the course
(trees.) Apparently it is also a bit easier to differentiate between
reflections and the real signal.

I might add that the signals are AM over there, and not FM as is
commonly used here in the US.

As far as hiding, ARDF transmitters are identified by an Orange/White
Orienteering flag that are usually visiable from at least 10 or 15
meters away. Unlike some of the mobile hunts I've been on, the idea is
not hider vs hunters, but rather to provide a fair venue for hunters to
compete against themselves. The challange is navigation, not trickery
:).

If anyone is interested in the Region I ARDF rules, they can be seen at
http://www.ardf-r1.org/, and look under "ARDF Rules".


bob wrote:
> 
> Why did they decide on horizontal antennas? Verticals are so much easier
> to make, hide etc.
> 
> I will be building one and probably use it on an up coming mobile hunt.
> It will make for some very interesting reflections from the bottom of a
> canyon.
> 
> I notice that you crumpled the 90 degree phasing harness into a wad and
> stuffed it into the pipe. The outer conductor of the phasing harness has
> lots of RF on it and this isn't a good place to put it. Better to let it
> dangle with the coax. You could also dangle a 1/2 wave loop for a balun
> (although it doesn't have RF on the outside and could be crumpled up),
> removing most of the RF on the feed line.
> 
> Bob, WB6JPI
> 
> Jay Hennigan wrote:
> 
> >I've assembled a number of these recently.  Details here:
> >
> >http://www.west.net/~jay/turnstile.html
> >
> >Comments, criticism, flames, etc. welcome.
> >
> >
> >
> 
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