Walter Maxwell wrote:
The following is Ted Hart's response to me:
----- Original Message -----
From: Ted
To: Walter Maxwell
Cc: Bill Ronay
Sent: Tuesday, January 13, 2004 5:50 PM
Subject: EH Antenna
Hi Walter,
Every one is entitled to their opinion - but accurate test data is irrefutable.
Boy, he finally got something right...Yes, accurate tests results can
tell a lot. *IF* we get ever get to see any.
Testing a non-decoupled very small antenna that is mounted to a metal 90
foot tall tower is not accurate test data.
It is a joke of immense proportion. The BC tower in close proximity
bothers me less than this. He is not testing an E/H antenna. He is
testing a 90 ft tower and feedline, being the problem of common mode
currents on the feedline are severe. Even he admits that "rf in the
shack" can be a severe problem with these antennas. But!!! He advocates
NOT using any form of feedline decoupling. It's no wonder, being that
will effectively kill the radiation from his main radiator. Which is the
feedline and tower. Someone, maybe from "Antennex", tested an E/H
antenna fed directly from the base of the antenna, with NO feedline, and
NO tower. Needless to say, the performance was earthshaking.
Or
maybe we should say it's non-performance....But when you have plans to
unload these buggers for appx 40k+ apiece, I guess the motivation for
*creative* testing really kicks in.
Accurate testing goes out the back window. An accurate test result will
not fit the program. The prince becomes an ugly wart infested fraug.
http://search.yahoo.com/search?x=wrt...eb-t&n=20&fl=0
http://www.google.com/search?hl=en&i...=Google+Search
for some more reading.
When he does a controlled test where the antenna is mounted on a
non-conducting tower or mast, and feeds the antenna directly at the
feedpoint using NO feedline, or at the least, a very well decoupled
feedline, then you can call it an accurate test. What he offers now is
an insult to most peoples intelligence. It's an insult to mine, and I'm
just a run of the mill dummy compared to many others on here. I suspect
most *real* broadcast engineers snicker like small school children when
they discuss the merits of the E/H antenna behind closed doors.
MK
--
http://web.wt.net/~nm5k