Satgen 586  Ionospheric Mayhem  by GM4IHJ  (BID SGEN586)   2000-06-17

Like the weather , the ionosphere can be a highly variable medium.
However one must not take the comparison too far . Living in a place
that still shows the signs of two enormous ice ages ( 25k to 1000k
years ago and, a little earlier around 620 million years ago). I
suppose we should be grateful that the Ionosphere does not presently
exhibit extremes of that nature. Although nurtured and cosseted by
the two most recent super solar maximums , the present non maximum
with its weird variations is a little hard to take.

All doppler feathering of RS13 signals viewed from IHJ as the
satellite crossed middle northern latitudes, has gone, and with it
all hope of terrestrial 6m DX appears to have gone too. But we do
have lots of Sporadic E. Which confirms by its presence, and the non
presence of doppler anomalies on RS13. That the two phenomenon are
not the same. A theory until recently being touted by some
transatlantic correspondents. Which has now been thoroughly
torpedoed.

The SpE also confirms that it has not lost its ability to interupt 2m
uplinks to satellites, and , to block 10m signals which intercept the
SpE on their way down from satellites. Though in compensation it has
provided some excellent 2m terrestrial DX ,  to Greece and Albania,
for at least one alert GM.

But as grandmother was wont to say. "A good storm usually washes
something useful up the beach". In this case, solar storms and
terrific polar zone magnetic activity. Which has made RS13 polar
passes great fun , with signals 100 Hz wide. Passes have been visible
on the FFT display from overhead both the north and the south polar
ice caps. Because, by some freak , although RS13 sub horizon
propagation from everywhere else has disappeared ( with the exception
of a couple of SpE assisted event). The propagation from RS13 when it
has been near the south pole , has continued to put signals into
Scotland almost every day.

APOLOGY.  To readers of Amsat Journal for May/June 2000 .
The article by this author on page 10 has suffered loss of one
illustration, duplication of another, and a confusing mix up of
titles on the figures.

Should anyone want a copy of the orignal. Please send details of your
postal address, to gm4ihj@branegan.demon.co.uk  , and I will forward
it to you. I hesitate to send it email. Noting that the emailed
original was, at the request of the ISP, divided up into about 12
parts or more. Which together with late supply to the editor,
probably caused the printing glitch.