[amsat-bb] Ham Science using PSAT PSK31 HF xponder

Robert Bruninga bruninga at usna.edu
Sun Aug 6 16:38:49 UTC 2017

Some people have reported difficulty getting into the BrnoUniversity PSK31
HF uplink on PSAT(NO84) and we just realized that such reports could be
valuable data that we have been ignoring.!

For our next HFSAT we want to explore how often the ionosphere bends the
uplink down below the satelite and any given station is unable to get in
even though their tracking program shows them the satelite is in view.  We
just realized we can get all this data simply by monitoring the PSAT
transponder and when people see AOS and LOS.

WHen we are looking for success (DX via the transponder) it is human nature
to ignore passes that didn't work.  But in this case, that is the science
data that is more interesting.

But then there is also another problem with "negative reslts" is that you
have now way of knowing if the resason you got negative results was becuase
of a vist by Murphy or because in fact, the negative effect you are looking
for was the cause.

So the best data is from a relatively high pass where you domt start seeing
your downlink until the satelite gets above X degrees elevation and then
gets strong and then fades out below Y elevation on the other side.

An ideal report might be something like:

DATE, STARTTIME, AOS angle, Max angle/AZ, LOS angle, ENDTIME, SUn AZ/EL

The sun direction will be helpful in explainign difference in AOS and LOS
elevation angles.

Its just an idea if aonyone wants to dabble in some Ham Science...


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