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Hi all,
At Quartz Hill we have similar observations to
Steve, in that we have not noticed a fade using the tx antenna for rx, but we
have noticed fades on loop antennas. Temporary one turn receiving loops
were supported by ropes to poles in suitable directions for receiving the DX
station, and the area was large enough that QRN swamped the receiver
noise. The loops were in the vertical plane and fed at a bottom coner
closest to the operating room. There is no QRM at the rural Quartz Hill
site so the large tx antenna can deliver a good result (that is
definitely not the case in my suburban QTH, neighbourhood QRM is quite a
challenge, my top loaded vertical for tx is hopeless on rx). But getting
back to the theme of rx loops versus verticals, I can say there have been
unexplained loss of reception from a loop when the vertical delivers a
satisfactory result. At Quartz Hill (ZM2E) we no longer use a loop for LF
rx, instead we have a splitter and feed all receivers from the tx antenna (a
changeover switch prevents use from having a very short distance
contact).
73, Bob ZL2CA
----- Original Message -----
Sent: Sunday, March 19, 2006 10:32
AM
Subject: LF: Re: LOOPS V VERTICALS
>Your comments on the
smaller verts/loops welcome.
Mal - during our last TransPacific tests with ZL,
we had the opportunity to run two rx's on the ZL frequency. One was our
mainstay and always reliable performer, the large 10' air-core tuned passive
loop while the other was our large vertical tx antenna. The ZL signal was
often 'O' copy on the vertical while the loop showed nothing at all. I think
there was only one short instance when the loop produced a signal that the
vertical did not hear. The loop had previously earned our respect as an
excellent rx antenna because we had always used it in our own noisier
environments but beside the ocean on Pender Island, there was no
noise at all, and the loop quickly lost it's main advantage. Both Scott and I
have since been using our tx verticals on rx at our home stations more often,
when the noise level permits and the verticals are clearly better, when noise
is not a factor.
BTW, our next TransPacific ZM2E-VA7LF
attempt is fast approaching...April 3-5th our time.
73
Steve / VE7SL
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