Delfi-C3 Launch Information

Wouter PE4WJ has provided further information on the launch of Delfi-C3, which is expected on Monday 28th April at 0353 UTC, and requests telemetry reports.

David M0MRF asked this question on the AMSAT Bulletin Board (AMSAT-BB)

"I've loaded the keps from the web site, and it looks like the first stations to hear the satellite will be on the west coast of the USA at around 05.01 when the satellite exits eclipse heading north. Can anyone confirm this sounds about right?"

Wouter PE4WJ of the Delfi-C3 team provided this answer:

Hi David, you are totally right. Indeed, Delfi-C3 will first exit eclipse over the US at 0501 UTC and this is the chance to hear the spacecraft boot up and hear its very very first signals. (The satellite has no battery so is not active in eclipse) So we would like to ask hams especially around the Western US and Alaska to listen to the spacecraft during that phase.

Telemetry downlink is on continuously, approx 1 frame every second. A sample recording of the 1200bd BPSK AX.25 downlink can be heard at http://www.delfic3.nl/photoblog/
wp-content/uploads/2008/02/delfic3_sciencemode_tm.wav

If all goes as planned, the spacecraft should come up on the primary downlink frequency of 145.870MHz broadcasting AX.25 telemetry, but please also check the backup downlink at 145.930MHz (also AX.25, similar signal as the primary freq) in case nothing is heard on the primary frequency.
The downlink is continuous, periods of no data are filled with flags, similar to AO-16.

Keep in mind to tune for Doppler, and when using RASCAL, tune 1600Hz lower in frequency when using USB mode in order to center the signal at 1600Hz. (This also holds for those who set the freqs in a SATPC32 file) In any case, tuning around slowly would probably be the best strategy, due to TLE uncertainty and spacecraft transmitter frequency drift caused by temperature variations.

The spacecraft will most likely be tumbling, especially during this phase, so note that polarization fades might occur. It is advantageous to switch polarization if you have the ability to do so.

If you hear Delfi-C3, please send reception reports to missioncontrol@delfic3.nl and state the following items:

-your name / callsign
-your location (Maidenhead gridsquare or latitude / longitude)
-time of AOS & LOS (UTC)
-frequency
-signal strength
-equipment (antenna, receiver)
-please record a wav file if possible
-please decode telemetry if possible with the RASCAL software. If you use a PSK TNC instead, please append a KISS (.kss) file

More info on spacecraft modes / freqs and latest TLE's can be found on our Mission Operations Page at:
http://www.delfic3.nl/index.php?option=com_content
&task=view&id=93&Itemid=122

RASCAL can be downloaded at:
http://www.delfic3.nl/index.php?option=com_content
&task=view&id=94&Itemid=123

Also, if you have listened for the spacecraft but not heard signals, please do report "nothing heard", since this still is valuable information to the team.

Thanks on behalf of the team, everything is good to go now!

Wouter Jan Ubbels PE4WJ

Join the AMSAT Bulletin Board AMSAT-BB at
http://www.amsat.org/amsat-new/tools/maillist/maillist.php

Satscape Satellite Tracker:
http://www.satscape.co.uk/

For frequencies of all the Amateur Radio cubesats on this launch see Multiple CubeSat Launch Set For April 28
http://www.amsat.org/amsat-new/index.php