Satgen390     Satellite HFDX Propagation  by GM4IHJ       14 Sep 1996

SEVERAL STATIONS ARE STILL PERSISTING IN ALTERING THE BULLETIN
IDENTIFIER BID OF THESE MESSAGES. PASS ON THE MESSAGE WITH ORIGINAL
BID. ALTERED BIDS BLOCK THE SYSTEM WITH USELESS DUPLICATES

Despite the obvious lack of normal terrestrial propagation at HF radio
frequencies, at this period of minimal Solar activity, users of mode A
and K satellites have recently had a series of opportunities for
contacts out to 6000 miles. On 30th August at 1454utc the IHJ computer
FFTDSP4 display in Scotland was monitoring the RS12 downlink, and
there was G3IOR in Norwich England having a CW qso with Ron,  7Q7RM,
in Malawi . All of 7000kms away direct via the mode K of RS12. When
the satellite far from being between UK and Malawi, was actually over
Central Greenland far to the northwest of UK, on G3IORs horizon, and
way below 7Q7RMs horizon.

One look at the globe should give anyone food for thought about this
contact where both signals were also being received in Scotland. How
did 21 Mhz propagate from Malawi at 10S 34E, to a satellite over
Greenland,  just 1700kms from the North pole . A fluke ? Not so as Pat
and Ron demonstrated by doing it two days on the run. 

Which raises another aspect of this affair, whereby shortwave/vhf
listeners can monitor these exotic DX contacts on the RS12 mode KT 2m
downlink between 145.91 to 145.95 Mhz (as well as 29.41 to 29.45),when
ever RS12 is above their horizon. Indeed further study of this DX
window on subsequent days has produced a feast of signals from North
America into Europe when the satellite was firmly over Europe far
below the American horizon.

So in an effort to check what was going on this seemed to be a good
time to monitor Internet on :- http://www.geo.mtu.edu/weather/aurora
which has a host of surfing off points, for reports of all kinds in
regard to Solar and Ionospheric physics. 

This is a yet early days. But with Internet and the RS birds we have a
fantastic combination for Ionospheric research. Clearly some of the
good sat DX of the past two months has coincided with Polar
Ionospheric Enhancement events subsequent to Solar outbursts. But that
does not seem to be the whole picture. If perhaps several station can
be persuaded to monitor these two sources ( Internet and actual
satellite downlinks) , we may have the makings of a very valuable
experiment.

What is certain is, that anyone can join in. All you need is a 2m and
or HF receiver. Even better if you have an HF transmitter , you can
make your own contribution to the, DX versus Ionospheric data records,
over the next few year, as the Solar activity starts to rise again.
With A010 busily FMing and not strictly usable, and, Ao13 soon due to
experience the satellite version of a Viking funeral. These HF
satellites and Fuji will soon be, the only game in town.