>How would you best set up a remote topband listening station? I want to
move
>my K9AY away from buildings and QRN. We own a piece of land "by the end of
>the road" and I am thinking of setting up an extra RX antenna there as it
>would be more quiet and in general is a better location.
>Coax is out of the question but the distance is less than 1 km. I assume a
>good receiver at the site and some kind of IP link so it is easy
>controllable. Everything on the RX site needs to run on 12 volts.
If the path is line-of-site, you could probably heterodyne part or all of
the MF-HF
band RF on a near-infrared laser TX and down convert it with an IR optical
RX converter at the other end.
I helped K3PGP with a laser heterodyne system back in the early 1990s and
it was surprisingly
easy. We used multimode 2M transceivers for the I.F.s and that worked
great.
An old projection lens from an 8 or 16 mm projector makes a great
collimator for TX and there
are some low cost optics around for the IR RX converter detector. Since
topband is a night time RX the signal to noise would be low and a 1 mw
laser would easily make the path. Cold optics filters are in most CD
players and so are the laser TX/RX heads. If you search google for K3PGP
and WA3TTS you should find John's experimenter page and all the laser info
from his experiments. (www.k3pgp.org/scope.htm, click on the
"construction" and "laser" links at the bottom of the page). Mike WA3TTS
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