Cubesats away!

April 27, 2008 | Amateur Radio | By: Mark VandeWettering

Well, the satellite launch that I’ve been waiting for happened. On the first pass I thought I was setup to record the Delfi C3 telemetry, and even thought I heard a signal, but it turns out it was probably just a local birdie. The second pass of the satellite cluster was only a 9 degree pass, and this time, I decided to focus on SEEDS, which I had heard was actually heard during the first pass. I recorded the following, just using my voice recorder:

SEEDS recording, second orbit over the west coast

I can read out the letters S E E D S rather easily, so I am pretty sure this is it.

Addendum: I ran the audio through my crude spectrogram code, and got the following picture of one of their telemetry packets…

SEEDS telemetry

Each vertical column represents 1/50th of a second of audio.

Addendum2: Here’s the same image, but with the decode overlaid.

SEEDS telemetry, labelled

If I read the telemetry documentation correctly, this is a G0 mode message, and D19 indicates that the lithium/ion batteries are at 4.1volts, and the bus voltage is very nearly 5v.