Tag Archive | telemetry

A SwissCube not made of chocolate

Another CubeSat I have been tracking from our ground station at F’SATI is the first Swiss satellite called SwissCube. This CubeSat has been doing its thing for almost two years and appears to still be doing well. It has a CW – or morse code – beacon transmitting at a frequency of approximately 437.505 MHz, a rate of 11.8 words per minute and has an output power of 100mW. It carries a low resolution camera as payload.

If I remember correctly I generally track this CubeSat with the LNA (pre-amp) switched on, which makes quite a noticeable difference. On Friday I could still receive a signal from the satellite with our ground station even after SatPC32 was indicating that the satellite was below the horizon (elevation < 0)! This could just have been due to favourable atmospheric conditions or even “oldish” TLEs – but still pretty cool.

The audio morse code tones are turned into text using MixW and can then be decoded using the decoder from the SwissCube website or the decoder from DK3WN. I happened to use the one from DK3WN.

Below is some telemetry from 16 June 2011 and also a figure of the decoder with the decoded information.

HB9EG/1
A T VV 
U VUE VUE 
V TATUTA 4A
SwissCube-20110616 decoded telemetry

SwissCube-20110616 decoded telemetry

And some telemetry data from Friday, 17 June 2011:

HB9EG/1
A T VV 
U VU4 VU6 
V TT4TTT 4A
SwissCube-20110617 decoded telemetry

SwissCube-20110617 decoded telemetry

The three messages respectively indicate the status of each major-component of the spacecraft, solar panel current and battery voltage and temperature. The solar panel current is given in ranges rather than specific values, for example Cell -Y is producing a current of between 500 and 626 mA.

Hope Oscar 68 (XW-1)

I have yet to hear from Delfi-C3 again, but in the mean time below is some CW telemetry data from HO-68 decoded with MixW on Friday (10 June 2011). According to one of the Delfi-C3 team members the CubeSat’s transmitter drops out intermittently and functionality is only restored once the spacecraft goes through eclipse and resets (Delfi-C3 has no batteries on board). Cape Town is its last `stop’ before the spacecraft goes into eclipse again so the likelihood of its transmitter having dropped out by the time it is over head is large, I guess.

I have also experienced quite a bit of interference around 145.870 MHz, the frequency at which the primary telemetry downlink is for Delfi-C3.

I have still to try and decode the messages below, but here they are in anycase. Most of the payloads on HO-68 is non-operational but the CW beacon is still active at 435.7900 MHz.

OSAXWXWAAATTTAA6AUEETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAA
              EAA6AVEETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6T6EETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6TDEETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTEA6T6EETTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1S
    UWDWTAATTTEABEAEETTTTTTTTTTTTTTTTTTTTTTTDAUW
EW1SAXWXWAAATTTAA6TBETTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6TNEETTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6A4TETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6AETETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6TBTETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6AVEETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW
BJ1SAXWXWAAATTTAA6TBTETTTTTTTTTTTTTTTTTTTTTTTTTTXWXW

In the next week or two I will try to start setting up our two TNCs and find some satellites with active data/packet payloads to test them. I might also start posting some information and pictures on our equipment and current setup. Last week we also received our SignaLink USB sound card.