Satgen154  ZL Experiment on RS12        by GM4IHJ             8th March 92

The past 7 days have seen some remarkable RS 12 Mode K DX, some of which
will take years  of experiment before we can explain it. We have had half
Europe hearing ZL3GQ and trying to get a QSO, plus signals appearing 80 to
100 degrees away from the senders great circle bearing, and doppler
effects which presently defy explanation.

On March 1st and 2nd, 0500 to 0900 ut,ZL3GQ had a pre arranged schedule
with G3IOR, G3LDI and G3MNP. At times ZL3GQ was 56 into Europe via RS12s
21MHz downlink. But though the 21MHz path ZL to RS12 (over Europe) was
excellent, the return 29Mhz path back to ZL to tell ZL3GQ he was
accessing, was never consistent enough for a QSO. Now with RS going into
full sunlight for a month or so, we may have to wait some time for another
chance.

In addition to the ZL access to RS12, it was interesting to note that the
ZL direct ionospherically propagated 21MHz was coming into Europe very
strongly. BUT IT WAS ARRIVING ON A BEARING 80 DEGREES removed from the
great circle path Eg arrival 100 degs azimuth. In addition to this while
ZL access to RS12 had been anticipated as peaking when RS12 crossed the UK
to ZL great circle, the actual peak downlink rebroacast from RS12 occured
when RS was over Italy , roughly 100 degs azimuth from UK. ie RS was also 
hearing the uplink non great circle.

At other times this week RS12 signals have shown marked doppler shift
anomalies, featuring doppler up just before AOS, and doppler falsely high
just before LOS. In another trio of incidents the doppler stepped 400Hz
approx suddenly as the satellite neared LOS.

Most of these features have been seen before. RSGB Space Radio Handbook
has details, but the sheer amount of Anomalous propagation on RS12 at this
time is very startling even to this writer who has been following sats of
this type for the last 15 years.

Radio Amateurs in other parts of the world can expect similar effects.
South America below the Equator is in range of UK around 1130 ut, and
stations in Eastern North America should get results from near Antipodeal
situations (Eg W Australia), as the Gs are doing around 0500 to 0900 ut.

Lights on NOAA sats. Agree with G8BKE that the report that a new NOAA will
carry a halogen light "to illuminate the earth for its pictures" sounds
April 1st a month early. PERHAPS If fitted the light would aid alignment
of the picture scanning mechanism. Meanwhile will wait for NOAA to explain
73 de John GM4IHJ @ GB7SAN