(no subject)


From: Cecil A Moore (Cecil_A_Moore@ccm.ch.intel.com)
Date: Mon Jul 14 1997 - 12:13:00 EDT

>From: k5zty@juno.com (WILLIAM A STIETENROTH)
>I haven't seen anything from our resident antenna gurus, Cecil
>and L.B., on this one.

Hi Bill, I'm not an antenna guru, just a guy who remembers what
my Elmer taught me 45 years ago which had primarily to do with
balanced transmission lines and doesn't usually apply to
vertical antennas. And I've lost every argument with L.B. except
one ended in a draw. :-) I don't learn anything except when
I'm wrong.

>The basic function of radials on a ground mounted vertical is to
>provide a low- loss path for ground currents...

I agree with everything you said. It takes more than 100 radials
to get optimum performance out of a *ground-mounted* vertical and
the longer the radials, the better. Salt water is the best radial
system and I haven't seen anyone divide salt water into 1/4 WLs.
How many radials do you suppose an AM broadcasting station uses?

If one has interference coming from one direction, removing the
radials in that direction will attenuate the interference as
well as the transmitted signal because the ground currents in
that direction are forced to flow through lossy earth.

There's an article in the spring "Communications Quarterly" that
raises some questions about unbalanced currents in 1/4 WL elevated
radials - interesting reading.

73, Cecil, W6RCA, OOTC

Search QRP-L Archives

[ QRP-L Archive | ]
[ 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 ]


This archive was generated by hypermail 2b29 on Fri Jun 02 2000 - 11:34:02 EDT