Thank you to all who have commented on the electronic noise cancellers by
Timewave and MFJ. I'm still browsing the archives.
My tx antenna is a full size quarter wave vertical with base insulator and
120 quarter wave radials. While it is a fantastic transmit antenna, it is
pretty sorry for reception. I built an indoor, rotatable, 5' X 5' shielded
loop that worked FB when I had the shack in the house (with non-metallic
roof). When I moved to my separate shack about 10 years ago (with tin roof)
the loop became almost totally ineffective - almost as noisy as the
vertical, and all the signals null at exactly the same point as the noise.
This summer I constructed a small square horizontal receiving loop fed
diagonally at each corner with open wire line, as described in the two
articale in Sept 95 QST. Although I occasionally get good results with it,
for the most part this antenna was a waste of time, usually giving little
noise improvement over my rotatable loop, while delivering so little signal
that internal receiver noise becomes a problem. Has anyone had any kind of
good results with one of these antennas? So far I have found no discussion
in the archives. Have not yet tried flag, pennant or ewe.
Over Xmas holiday, I put up a 400' terminated Beverage, 10' high. It seems
to be my quietest antenna, although not too directional. However, it is no
panacea, picking up certain types of noise almost as strongly as it comes in
on the vertical.
If I do attempt to use one of the noise cancelling gadgets, I will try to
reduce the noise pick up on the Beverage, using a separate noise antenna
near the power lines.
BTW I have found an inexpensive noise sniffer at Radio Shack. They have a
little portable AM/FM radio with aircraft band (108-132 mHz AM). Costs
about $30. I can usually pinpoint noise right down to the pole by riding
and walking around, listening on the aircraft band. However, the present
noise source has been more elusive. One problem is, driving down the road,
the ignition and alternator noise in every vehicle I own completely masks
the noise, and people drive like such maniacs that I am afraid to use my
bicycle for this.
73, Don K4KYV
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