You all know Ivan, VE3DO....he is the fellow who posts all those rare DX
spots which most of us often cannot hear on our Beverages or other
receive-only antennas. Well, the secret is out....Ivan has a "new" antenna
design which I refer to as "the DO Loop", and he was kind enough to share
his
"secret".
This loop is fed the same as a K9AY but it is rectangular, with dimensions
40 ft
horizontal and 10 ft vertical, with the lower horizontal wire just clear of
the ground. I have built two of these with lower wire 18" above ground. I
use the BN73-202 core wound 9:1 with separated winding and the coax shield
NOT grounded at the feedpoint. Ground rod is 3-4 ft in each case.
The antenna is VERY quiet and its gain appears to be close to that of the
K9AY loop, so you need some amplification (in my case I use a W7IUV 20 db
preamp). At my home QTH I can hear the JAs and sometimes AH2L in the
morning when they are often buried in noise on my 1000 ft Beverage. The "DO
Loop" also hears better than a pennant oriented in the same direction. I
don't know why this design seems to work better, but after seeing all the
posts
for stations Ivan has been hearing the past couple of years I decided to try
one.
The first was installed at our summer home where the comparison antenna is a
"boomerang" Beverage 600 ft long. This antenna, sloping right down to the
water on Lake Huron, is very quiet and hears extremely well-but the DO Loop
hears as well on most occasions and better on some. The second loop was
installed at the home QTH.
Perhaps someone out there can suggest why this design hears as well as it
does....I am not enlightened on such subjects! It may not suit everyone's
needs, but testing over the past few months seems to indicate that this
design seems to hear the DX when the Beverages cannot. I have been so
impressed by its performance that I plan
to install a quad of them in the pasture next summer to complement the
Beverages and pennant I have at present. After all, one can never have too
many RX antennas!
Merry Christmas,eh!
73, Bill VE3CSK
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