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AO-40 sounded great on Sunday


I had some really easy QSO's from the UK into Europe and North America on
AO-40 on Sunday 20 January 2002 between 10:15 and 11:20 GMT when the bird
was just restarting its new orbit. South America was in view too but there's
not much activity from there.

Time (GMT)      MA      Squint   Range (km)
10:15            9        39       12,700
10:45           15        22       19,200
11:15           22        22       25,300

So despite the appalling squint, this was offset by the close range of the
bird. There was also some QSB which occurs at larger squints: either due to
polarisation mismatch or because the motor nozzle gets in the way at higher
squints [assuming there's still a nozzle there ;-) ].

Similar conditions occur with AO-40 every four days, but 25 minutes earlier.
For instance on 24 January 2002, at 09:50 or so the same conditions will
occur, assuming the spacecraft's ALON/ALAT has not changed significantly.

Catch the bird early in the orbit between MA's 9 and 30 and you should
certainly have no problem hearing it, and you should be able to work it too
even with the current ALON/ALAT of 300/-8!

Indeed, this situation is extremely reminiscent of our QSO parties back in
May 2001 when the transponder was first switched on and many of us were
using helices and not dishes. At one point on Sunday as an experiment I
pointed a 6" long 7 element yagi in the general direction of the window and
was picking up Q5 SSB QSO's at a range of 17,000km.

Of course, the timing of these conditions will vary widely depending on your

73 Howard G6LVB

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