[amsat-bb] Further indoor, ultra-cheap antenna success

Bruce Robertson ve9qrp at gmail.com
Thu Jan 24 12:46:34 PST 2008


Following my experiment reading AO-16 last night with an indoor
1/4wave magmount, I'd hoped to try today with a basic antenna attached
to my FT-817. this antenna is a BNC connector with three stiff copper
wires attached, two to the ground, one to the pin, in the classic 120
degree arrangement.

Alas, by the time I made it home, the bird was only at about 2 deg,
over the N. pole  (its silence quite possibly due to inactivity) so I
switched to CO-55's nominal 100mW CW signal. Again, indoors through
about three walls and perhaps the roof of this wood-frame home I was
able to hear CW. I engaged the narrow CW filter, which then made it
intelligible, and  then walked toward the other end of the house so
that a single outer wall was between me and the bird. At about 2 deg.
elevation to the North, I could no longer copy the CW. It was about a
559 until then.

Granted, my house is surrounded by a 6 acre field and on slight hill.
I have very little noise on 435MHz that I can tell. Nevertheless,
there was enough of a signal above the noise that I think this could
be reproduced easily in many locations. It strikes me as a very simple
experiment, ideal for in-class or for a demo to a ham club. In fact,
the constancy of the cubesat telemetry makes the demonstration easier
to understand and conduct.  One could get the sat tuned in then hand
the knob over to someone else so that they can 'feel' the doppler as
they catch up with the bird.

73, Bruce
VE9QRP


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