[amsat-bb] SO-67 Audio 8Nov2009 1552z over US

[John Papay]

The audio file of the 1552z 8November2009 SO-67 pass
over the central US is on my webserver:

http://www.papays.com/SO-67_08Nov2009_155053z.mp3

It is not clear as to why you get a few seconds of
transmission and then are cut off.  Since the satellite
is being turned on for a specific period of time, one
way to determine the effect of the sub-audible tone is
to simply turn it off and put the bird in carrier squelch
mode.  The repeater is on continuously anyway for the
duration of the time period.  Having no PL tone will
allow us to see if it is something else that is causing
the drop outs, for example, over deviation, multiple carriers
etc.  The PL tone is very close to the normal speech frequencies
and that can cause problems.  Tone frequencies between 100Hz
and 150Hz will still decode quickly and not be subject to speech
audio interfering with the decoding process.  Just some ideas
for consideration.

This was only a 12 degree pass for me here in Ohio, however,
I copied the bird on this pass using the new Alnico DJ-G7 handheld
with the stock rubber duck antenna.  Signals were amazingly strong
although subject to severe fading at times.  It should be possible
to work through this satellite with a rubber duck antenna once the
access problems are minimized.  This will bring many more amateurs
to the satellite part of the hobby and may peak their interest to
be able to hear the weaker satellites as well.

Congratulations to AMSAT-SA for designing and launching this amazing
satellite.  We look forward to having it around for many years.

73,
John K8YSE EN91dh Ohio


John Papay
john at papays.com