[amsat-bb] Looking ahead: AO-51 38k4 packet Nov 16-19, 2009

Mark L. Hammond marklhammond at gmail.com
Fri Nov 13 04:10:36 PST 2009

Okay 38k4 packet operators, get ready to start your engines!!

AO-51 is scheduled for a four day period of high speed packet
operations at 38k4 bps.   If memory serves me correctly, it's been
about 2 years since the satellite was configured in this mode.  The
satellite will be in high power mode (only TXA 437.150 transmitter ON)
during this period.

The posted schedule is as follows:

November 16 - November 19

38k4 BBS, L/U
Uplink: 1268.700 MHz 9k6 FM
Downlink: 435.150 MHz 38k4 FM

Usually this means the mode will run from around 22:00-23:00UTC
November 15 (Sunday evening Eastern US) until around 22:00-23:00UTC
November 19 (Thursday evening Eastern US).

Users of the PacketBBS are encouraged to send me feedback/reports on
your experiences during this period.

Please note that 38k4 packet operations require a receiver with
sufficient bandwidth and that your normal 9600 radio receive
connection will not work. Users also need a TNC that is capable of
running packet at 38k4.   A special "wide" filter like the ones
available through Symek (www.symek.com) need to be installed in the
radio to "tap" a wide band signal.  A few commercially available TNCs,
like the KPC-9612+ and the Paccomm Spirit-2 (with satellite option)
can be used.

You can use a PCR-1000 or PCR-1500/2500 as a wide band receiver,
without modification.  Use the packet jack and set the receiver to FM
(not FM-W) with a 50 kHz filter width.  If you have one of these
receivers, but not the right TNC, you might try Doug Qualigiana's
KA2UPW sound card software here:  http://www.quagliana.com/willow/
It will decode at 9600 and 38k4.  There was a an article about his
software in the AMSAT Journal just a few months ago.

Hope to see you active on AO-51 at 38k4!

Mark L. Hammond [N8MH]

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