>
>
>Whatever it is, the goal on practical antennas for field comm is not
>necessarily to make the "best performing antenna", but to make an
>"adequately performing antenna" that meets all the other requirements. It
>might well be that they're willing to give up 10 dB of loss in exchange for
>adding a 500W SSPA. They're not going for maximum miles per milliwatt QRPP
>contesting.
I once put up an ionospheric sounding antenna in Puerto Rico that was a
complex wire array to cover 2- 30 MHz and it was strung between two 100 ft
towers that I had installed in a flooded field. The effort to
install two towers
in knee deep water was a real PITA. But the antenna did a good job and
the scientists were pleased with the results. And I was pleased because I
had done a good job on a "serious" array under trying circumstances.
A couple of years later I was in Alaska working on another project and a
university group had a 2-30 MHz ionospheric sounder that feed a dipole that
was made from two 10 ft long pieces of 6 inch diameter irrigation tubing and
this dipole was sitting on wooden blocks on the ground. The center of
the dipole was about 3 inches off the ground (actually the pavement) and
the tips were about 8 inches off the pavement with about 15 ft of feed line.
This antenna also got good results for the intended experiment and was
a heck of a lot easier to install.
Sure it was inefficient, but it did the job and it took 10 minutes to install
instead of two weeks and it was a heck of a lot easier to transport two
10 ft pieces of aluminum tubing than to transport two 100 ft towers plus all
of the wire array.
Personally I have always been a firm believer in the philosophy of "Too much
is just enough." As in "If a little does a little good, and a lot
does a lot of good,
then too much is just enough." But in actuality "Good enough is all you
really need."
W0UN
"Nothing exceeds like excess!"
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|