Steve G0KYA,
Often at dawn/dusk with a signal at the opposite side of the earth
(or near it) signals will flicker from SP to LP. W1EVT in Acton, MA who
uses Lazy-H antennas at 120 feet (one N/S one E/W) can switch between the
two and find that signals during sunrise or sunset actually are skewed and
arrive from the East when they should be arriving from the SW (signals from
Perth) for LP propagation on 7 MHz. I too, have noticed this with my rotary
beam on 40 meters. It seems that the LP/SP dual receive most often happens
at moderate frequencies - frequencies which can propagate either nighttime
or daytime. I remember that 8 and 12 MHz commercial bands were most likely
candidates for "extra" dits caused by multipath LP/SP propagation when
listening to the marine CW bands years ago.
One great hinderance to amateurs in the USA who like to work far DX is that
many have no idea of where the signals should be coming from as they rely
upon maps centered on the geographic centre of the USA which shows Perth as
due West while the majority of Australia is SW, but from Boston, Perth is
NNW and the rest of Australia just starts at West. Perth is aproximately
the same heading as Tokyo from Boston. Hams with beams who use the ARRL map
are beaming west to southwest - and probably won't even hear VK6.
Best Wishes,
David N1EA
----- Original Message -----
From: Thomas Giella KN4LF
To: PSC.Committee@rsgb.org.uk
Sent: Wednesday, October 20, 2004 10:07 AM
Subject: Re: [PSC.Committee] 10m not dead yet!
If you monitor the PSK31 propagation beacons on 28120 kc you will find 10
meters open in some direction via Es or F2 virtually every day that there is
no geomagnetic storming.
73,
Thomas F. Giella, KN4LF
Retired Space & Atmospheric Weather Forecaster
----- Original Message -----
From: Steve Nichols
To: PSC.Committee List Member
Sent: Wednesday, October 20, 2004 4:53 AM
Subject: [PSC.Committee] 10m not dead yet! {01}
Just heard Ross VK4CQ on 28.480 at 08:35UTC on 20/10.
He peaked at 56 before vanishing back into the noise. It looks like a case
of skip focussing to me as he was in his twilight zone. Strange thing is
at
that time of the morning it could be long or short path. Beaming SW
brought
the signals up at one point, but shortly after beaming NE was better -
strange!
I would have put my money on SP. Shortly after he vanished I could still
hear UK stations to the west of me working him.
Propagation is excellent at the moment. I have heard the West Coast USA on
17m and California was worked on 80m the other day from the UK in the
morning (not by me I hasten to add!).
Steve G0KYA
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