It's not quite a dummy load, folks. But it's not very
efficient. My only experience with it was in the marine
SSB bands. The Sea Education Association base used one to
communicate with its sailing research vessels, when my
daughter took a semester at SEA.
I was able to hear both SV Westward and SV Corwith Cramer
better than SEA HQ, simply using a 40m vertical GP.
It would have been illegal for me to TX on those freqs with
amateur gear, so I simply phoned SEA HQ and let the radio op
know what was being said, while my daughter was aboard Westward.
I WAS prepared to TX, if an emergency arose, in accordance with
int'l SOLAS law. It wasn't necessary.
The B&W topic was raised in two contexts. One, Jim Lux's modelling
efforts. The other by a chap who is looking for an ALE antenna.
Automatic Link applications spread over many bands, as we go through
diurnal ionospheric shifts. Is a -3dB or -6dB gain antenna useful,
to enable fast changes? Perhaps....and perhaps -10dB is not.
If I were contemplating ALE operation, I think I'd look seriously at
off center fed dipoles...and a modern implementation of same called
the Carolina Windom. That, with an auto-tuner, should be able to
handle the wideband requirements of ALE.
n2ea
jimjarvis@ieee.org
_______________________________________________
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.
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