Several years ago the ARRL reviewed a "magic" antenna made by Maxcon (I
think that was the name), that also had a "mysterious" black box attached to
it and sold for an outrageous price. X-Rays revealed what looked like an
encapsulated scrap PC board mounted in the box. I believe the ARRL rated
the efficiency of that antenna in the single digits or close to it. It
wasn't on the market long after that. If it had been designed for 11
meters, they probably would have sold tens of thousands of them and become
rich. :-)
Reid, K7YX
-----Original Message-----
From: Dr. Gerald N. Johnson, electrical engineer
[mailto:geraldj@ames.net]
Sent: Friday, January 26, 2001 8:02 AM
To: Billy Cox
Cc: Richard B Drake; tentec@contesting.com
Subject: Re: [TenTec] Broad Band Antenna
RIGHT ON! The B&W broadband antenna is a leaky dummy load. Might as well
use any coax fed dipole with a T in the coax hooked to a 50 ohm dummy
load to present a match to the radio.
I recalled that resistor was 200 ohms but at least one X-ray of the
module showed it had scrap pieces to confuse the X-ray. The design was
originally published in CQ magazine in the 50s as the T2FD. Terminated
2-wire Folded Dipole. Its main market seems to be emergency managers who
see the broad bandwidth and ignore the poor performance. I don't know
with the Iowa state EOC is using for an antenna, but Dec 31, 1999 I had
to regularly relay because the EOC couldn't copy signals that were solid
copy (despite the QRM of every state EOC sitting on the same frequency)
with a simple inverted V and my Corsair II.
73, Jerry, K0CQ
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