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  1Hz click external noise?         


Author: Lumpy
Date: May 18, 2008 14:39

Any guesses as to the origin of the mystery
noise bugging me this morning would be apprec.

I'm hearing an S9 "click" at just about
once per second, everywhere on 20meters
where there's not a powerful station's
signal. It clicks for maybe 3-5 seconds
then stops for a few seconds. Not always
symmetrical (3 sec noise ~ 10 sec no noise).

Click sounds like what I'd imagine a charging
and regularly discharging capacitor might do.

Freq independant, it's everywhere on the 20m phone segment.

S9+ stations seem to override the click.
S7 stations don't override, the click
comes right through and clobbers reception.

Station is "backyard remote", battery powered,
asymmetrical wire dipole.
Show full article (1.28Kb)
18 Comments
  Full-wave coaxial loop?         


Author: John Poet
Date: May 18, 2008 11:21

I want to erect a full-wave horizontal loop antenna for use around 3.5
mHz (as an NVIS antenna). The problem is, I don't have quite the
space to configure such an antenna, which would be somewhere around
280 feet long using normal wire. (Don't have my actual calculations in
front of me, but they are roughly these dimensions).

I've gotten the idea that I could shorten the physical requirement, by
using RG-58 coaxial cable instead of regular wire, and taking the .66
velocity factor into account--- turning an electrical length of about
280 feet into only around 180 physical feet of RG-58. (I have a 1000-
ft reel of this stuff). It would be fed with 300 ohm parallel lines
to an antenna tuner.

The questions, to those who may be more well-versed in the theory of
antennas, are 1) is my reasoning on the V.F. sound? and 2) if I
construct this, should I use the center conducter of the cable as the
active element, or the shield, or connect them together? and 3) Would
the shielding on the cable have any effect on the center conductor
being used as the antenna element?

JP
11 Comments