Dennis,
if the loop-preamp system is well balanced the loop doesn't need
screening.
E.g. the Wellbrook ALA1530 broadband loop is unshielded.
Therefore its preamp is a push-pull design.
73
Clemens
DL4RAJ
----- Original Message -----
From: "DENNIS EASTERLING" <[email protected]>
To: <[email protected]>
Sent: Sunday, January 16, 2011 11:15 AM
Subject: Re: LF: Re: Mini-Whip Antenna
Dear Roelof and Petr
When I first tried the mini-whip I was very sceptical of its
performance,
but in my circumstances, living surrounded by houses and near a main
line
electric railway ((25kV) it has performed very well indeed.
I tried tuned loops of various sizes but the qrm is overwhelming in
such
close quarters to the switched mode power units and machines
operating in
nearby houses. Out of various loops, the wide band untuned
screened loop
seemed the best option, with a simple 1m loop of co-ax cable and
amplifier
tied to the back fence and the Wellbrook ALA1530 giving similar
performance
at MF, although the Welbrook is better engineered and mounted on a
rotator.
...
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