Hi All
Last evening I had a chance to do a little test with Mike G3SED at around
2245Z. We compared my Xmit antennas (vert vs horiz) and I'll pass along the
results.
The horiz antenna is an inverted vee with the apex at 200 feet and the ends
pulled WAY OUT. The apex angle at the top of the tower is about 135 degrees.
The vert is a 96 foot Rohn 25 tower, base in concrete fed as a folded unipole
with a three wire cage. Atop the tower is a 2el 40m yagi for top loading.
There are 185 ground radials, all on the ground, of varying lengths - most
from 80 - 150 in length. There is pretty much full 360 degree coverage on
the ground.
We ran the test several times and Mike advised that the VEE was one full s
unit better than the VERT.
Then, Mike compared his antennas - a dipole versus what I think is an
inverted L with 75 foot of it vertical.
His Vertical was 2-3db LOUDER than his dipole at my qth and W1JBW, Powell,
in Provincetown on Cape Cod advised Mike that he was one full S unit louder
on the vert there on Cape Cod.
Pse note that this is the EXACT REVERSE of my xmit test.
I have run this test with Mike quite often - last week I think we did it also
and at that time the results were the OPPOSITE - at that time he said the
VERT was 2 s units LOUDER than the high VEE.
What does this all mean? Hard to tell....my own personal take on it echoes
what others have noted here on the reflector recently. Sometimes you gotta
hunt with a "bow" - sometimes with a "rifle." It's nice to have BOTH -
because 160m is a very unique band.
You just NEVER know what will work best - so it's best to be prepared for as
many types of prop/arrival angle as you can.
Interestingly enough, Mike also noted that at his sunrise, his DIPOLE is
almost ALWAYS louder into the USA - Go figure!!!
73 Jeff K1ZM
K1ZM@aol.com
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