[amsat-bb] CPX Data Decoder Software Available

Jason Anderson jander06 at calpoly.edu
Mon May 4 01:50:43 PDT 2009

So the CPX Data Decoder software is now available for download now at


Follow the link and click the 'Download' menu option.  This will take you to
the download page where you can download the software for your computer.
You will still need to have your own tracking software to control the rotors
and radio as our software simply links onto the output of your TNC.

Launch night will hopefully go as follows.  The rocket carrying CP6 will
launch on May 5th between 20:00 and 23:00 EDT.  Minutes later the rocket
will kick out our CubeSat into orbit.  Due to safety reasons, our satellite
will turn on 4 hours after it is deployed and will start to beacon every 2
minutes.  Each beacon is 6 seconds long and contains 4 seconds of CW
followed by 2 seconds of a 1200 baud AX.25 packet.

Unfortunately for tracking purposes, tuning will still be a minor issue as
it was with our previous satellites (work is being done on our next
generation Comm system which will hopefully make this issue disappear).  The
best way to combat our transceiver frequency drift is to start with the
calculated frequency and adjust the radio frequency manually as soon as you
hear a beacon.  This is part of the reason why we have 4 seconds of CW
before the AX.25 data packet.  One trick it to tune the the CW signal to
1200 Hz on a waterfall display (something like MixW if you have it) which
happens to line up the frequency to decode data packets.  Hope everyone is
up for a small challenge :).

As for the TLE required to track our satellite, we have created a very rough
predicted TLE.  We are told we will receive the actual TLE 4 hours after the
launch occurs which is approximately when our satellite will start to
beacon.  We will be posting the updated TLE as soon as we receive it on the
CP6 information page found at


We will also announce the updated TLEs in the CubeSat IRC room which can be
found at

     Server: irc.freenode.org
     Room: cubesat

If you have any questions regarding the software or trying to contact CP6
please feel free to ask.  Thanks for such a great initial response and I
wish you all happy satellite listening.

 - Jason Anderson, KI6GIV

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