[Xastir] RDF Units?

[Curt, WE7U]

On Sun, 27 Mar 2005, Jerry Chamberlin wrote:

> Ramsey iis the manufacturer

Thanks.  I'm looking at multiple possibilities, and found my DF'ing
book that had the theory behind them in it.


> PIC , be serious, simpler than that no code, just a 1 by 2, 2 antennas (real
> deluxe if you have a motor to spin them) and a BFO
> and a good set of headsets
>
> when the pitch is lowest your moving away from the source, when the pitch is
> highest you are moving toward the source

Yea, I build the double-ducky direction finder way back.  Can't
remember now whether I gave that away or whether it might still be
in the garage somewhere, but in any case it doesn't suit the current
application.

I need something that gives an automatic indication and can be
transmitted over APRS.  Pretty much that means doppler systems.

I have figured out through web searches that there have been a lot
of improvements since the DoppleScAnt.  I need switching noise to be
minimum, resolution to be as good as possible, and need it to work
with very short transmissions.  It's that last that I'm still
investigating.

Oh yea, and I need it to work over a wide frequency range.  That
knocks out quite a few of the designs due to the 1/4 wave pieces of
coax in the switching matrix.  I've already found the Moell wideband
antenna switching circuit that totally avoids that problem.

I received some private replies as well.  Thanks for the answers
everyone!

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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