Yaesu handheld and $50SAT 1.5U PocketQube

Michael Kirkhart KD8QBA reminds us that the PocketQube $50SAT has now been operating for two months. He writes:

It has now been 2 months since the launch of $50SAT into its 625 km (approximate) sun-synchronous orbit, and as of this morning [Tuesday January 21], it is still operating.

It is getting cold again in EN82 land, so it is not likely I will be able to gather RTTY telemetry during the next few days, as my trusty netbook will not likely be able to deal with the cold for very long. Hopefully, everyone else can “pick up the slack” for me. I will still go out and monitor passes, provided it does not get too cold.

$50SAT Boards

Since it was pretty cold this morning (about -12 to -13 degrees C), I chose not to record the pass at 15:24 UTC (10:28 AM local time). Instead, I monitored it using my FT-60. At about 15:36 UTC, I heard the codespeed on the FM Morse beacon drop, which indicates the availability of solar power. Using gpredict, I estimated the latitude of the satellite sub-point (the point on the Earth directly underneath the satellite) to be about 24 degrees N. Today, the sun is directly over 20.4 degrees south latitude (23.5 degrees * sin(270 + 30), as it has been about 30 days since the winter solstice). At the time I heard the beacon, the angle of $50SAT normal to the sun (assuming the passive magnetic stabilization is working) would be about 24 – (-20.4), or about 44.4 degrees. This means the solar radiation intensity is about 70% of its maximum value, which means the solar power generating capacity will be anywhere from 50% to 70% of its maximum, depending on whether one or two panels are facing the sun. But since I did not collect telemetry, I have no values for comparison.

I was able to collect RTTY telemetry on Sunday and Monday, and here it is:

2014-01-19,16:34,$$$$50jAT,128,,467,,,52,3,,21,142,82,,102,305,3662,*43
2014-01-19,16:36,b50SAT.128,,467,,,54,3,,21,139,82,,102,305,3683,*46
2014-01-19,16:39,$50SAT,128,,467,,,59,3,,21,132,83,1223cr}

2014-01-20,16:55,50SAT,128,,471,,,60,3,,21,132,83,,122,309,3683,*42

Michael Kirkhart KD8QBA
$50SAT team

$50SAT is one of the smallest amateur radio satellites ever launched at 5x5x7.5 cm and weighs only 210 grams. Transmitter power is just 100 mW on 437.505 MHz (+/-9 kHz Doppler shift) FM CW/RTTY. It uses the low cost Hope RFM22B single chip radio and PICaxe 40X2 processor.

$50SAT has been a collaborative education project between Professor Bob Twiggs, KE6QMD, Morehead State University and three other radio amateurs, Howie DeFelice, AB2S, Michael Kirkhart, KD8QBA, and Stuart Robinson, GW7HPW.

Further information in the $50SAT Dropbox https://www.dropbox.com/sh/l3919wtfiywk2gf/-HxyXNsIr8

There is a discussion group for $50SAT http://groups.yahoo.com/groups/50dollarsat/

50DollarSat http://www.50dollarsat.info/