On Tue, 30 Aug 2011 09:03:33 +0200, Helmut Wabnig wrote:
I wonder how important matching is for a pure direction finding antenna,

I don't think it affects sensitivity, which is not really at a premium
anyhow.

A gamma match seems to skew forward-max location a bit to one side,
which matters if you're relying on accurate bearings from a distance,
but overall it doesn't matter much - in some ways it's better to
expect to spiral in on the fox a little anyhow, I reckon.

The gamma match also goes wonky if you put your hand on it, but I
guess that's not surprising. many of the top competitors use them
anyhow - we have a design that's easy to disassemble to put into a
suitcase for air travel.

One of the guys built a much-enhanced version of the NEC software for
the Mac, and he's automated it to automatically optimise (millions
of individual runs with different combinations) a 7-element boom
for 70cm, which is yielding very impressive DF results right across
the band.

Clifford Heath.