Topband: Re: Noise and reception
Richard Karlquist
richard@karlquist.com
Tue, 19 Feb 2002 11:30:56 +0000
I think what has been neglected in this
discussion is the local noise environment.
If you have a low noise QTH (such as Tom
apprarently does), then it makes sense
that vertical polarization is the way to
go. Although my QTH is rural, farms
have power lines, and I have a fair amount
of trouble with power line noise, although
it comes and goes. Perhaps power line noise
can't propagate in the horizontal polarization,
making horizontal receive antennas relatively
immune.
I know this is the topband reflector, but forgive
me if I QSY to 75 meters temporarily. On long path,
everyone on the west coast agrees that receiving, not
transmitting, is the major limitation. Certainly
in my case, I can work anything I can hear, and
and then some. Only the strongest stations
from Europe are audible on my 1/4 wave vertical
(such as SM5RQ with his 3 element Yagi). My 300°
beverage is (guessing) 6 to 10 dB better than the
vertical. Luckily, that is a relatively low noise
direction in terms of power lines. Still,
nearby stations with 3 element Yagis generally
hear better than I do. There is one station
with a 4 square who seems to hear even better
than the Yagi stations. He attributes
his success to having his 4 square in an extremely
remote location, presumably without local noise.
Thus, my conclusion is that if you're not in a super
quiet QTH, you need a horizontally polarized receive
antenna.
Now, I agree that a loop close to the ground isn't
going to work horizontally. What I would like to
try is putting a loop oriented horizontally at 100+
feet up. I'm wondering if anyone has any opinion
on the chance of success of this idea.
Rick Karlquist N6RK