After my reply post to Edy suggesting he consider Earl's recent small loop
in place of the "magnetic" loop I received a number of replies asking for
the photos of the prototype I built from Earl's specs and EZNEC
model. Please see the web address below for the photos as it was very
timing consuming to send these out in reply to the emails.
This antenna is very simple - it's a mini diamond Flag - with a 660 ohm
terminating resistor and a 16:1 transformer. It is the exact size of the
so-called magnetic loops, - 5 ft per side, 20 ft total wire, and about 7.1
ft wingspan. It has classic Flag cardiodal pattern and, of course, pretty
low output (-50db from what I recall). F/B is about 30db. I use it with a
single preamp with good results. This antenna is quite easily rotatable as
you can see (altho the standard 15 X 30 ft Flags have been made rotatable
too as most of you know). This has several advantages over the "mag" loop
(for those on small lots) - it's broadband 1.8 mhz past 30mhz; cardioid
pattern with very nice null to rear, decent low angle take off (abt 32 deg)
AND is simple - make it in minutes. I used 2 - 330ohm resistors a
binocular 16:1 transformer. I "potted" the resistors and xfrmr in epoxy.
I've since cleaned mine up - routing the rg174 coax from the transformer to
the center of the crosses, then connect it to a rg58 run vertically down
the mast.
Thanx loads to Earl K6SE for the design.
73 Pete, W2PM
<http://members.aol.com/w2pm/small-loop>http://members.aol.com/w2pm/small-loop
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