2016 launch for UniSat-7 with CubeSats and PocketQubes

UniSat-7 GAUSS Srl

UniSat-7 GAUSS Srl

GAUSS Srl is preparing a Dnepr launch of a new satellite, UniSat-7, into a Sun Synchronous Orbit (SSO), carrying CubeSats and PocketQubes.

The launch is planned for December 2016 and they are currently looking for payload to include in their satellite.

If you are interested in including your own payload you can contact GAUSS Srl to assess the impact on the mission at launch@gaussteam.com there might be space left for your own payload/satellite.

Characteristics of the UniSat-7 mission:
• Total mass: 32 kg
• Sun-Synchronous orbit: (550 – 600 km)
• LTAN: 10:30 (confirmed)

Watch UniSat-7 Satellite
Music by Kostantinos Geradimos, Album Stereofloat, Song Crashed

UniSat-7 http://www.gaussteam.com/satellites/unisat-7/

Launching CubeSats For and From Australia

The 2015 CubeSat Workshop took place on Wednesday, April 1 at the University of New South Wales (UNSW). Videos of the presentations are now available on YouTube.

Among the presenters were representatives of two UK space companies, Tom Walkinshaw of Alba Orbital and Craig Clark of Clyde Space.

The presentation schedule and slide PDF’s are at http://www.acser.unsw.edu.au/events/cubesat2015.html

The videos are at https://www.youtube.com/channel/UCQ4pUVq3euPwUNX00If0FTw/videos

Watch 2015 Cubesat Workshop Session 2

$50SAT/MO-76: 15 months, 15 orbits per day, and some unexpected behavior

Yaesu handheld and $50SAT 1.5U PocketQube

Yaesu handheld and $50SAT 1.5U PocketQube

Saturday, February 21, 2015 marked the 15 month anniversary of the launch of $50SAT/MO-76, and you guessed it – it is still operating.

Thursday, February 12, 2015 marked a different milestone – its orbit has decayed to the point where its mean motion crossed the 15 orbits per day threshold.  The TLEs from Saturday, February 21, 2015 indicate it is now at 15.00521293 orbits per day.

Some of you noticed that something odd started happening on Monday, February 23, and Tuesday, February 24.  We also noticed the same thing – during daytime passes in the northern hemisphere, $50SAT was transmitting once per minute, always sending telemetry in RTTY format, but never sending GFSK telemetry packets.  Moreover, the total reset count kept going up by one each time.

Here are all the RTTY telemetry messages (that I am aware of) gathered on Monday and Tuesday:

(daytime pass)

(daytime pass)

(daytime pass)

(nighttime pass)

(nighttime pass)

(daytime pass)

(daytime pass)

(nighttime pass)

$50SAT Boards

$50SAT Boards

What seems to be happening on the decending (daytime) passes is the CPU is reset just after sending a full RTTY telemetry message, as here are no GFSK packets sent, but within a half minute the FM Morse beacon is heard with Stuart’s callsign (GW7HPW, the first one in the rotation).  My guess is the battery voltage is decaying during the operational cycle, and goes below the 2.9V reset threshold just after sending the RTTY or just as it is about to send the GFSK packets.  Once the satellite is able to enable solar power (PCB temperature >= 0 degrees C), it starts behaving normally; it is now able to send GFSK packets.  During ascending (nighttime) passes, it behaves normally, at least here in EN82 land.

There was a brief time where this behavior stopped (2015-02-25, 17:05 UTC through 2015-02-26, 3:47 UTC).  It did, however, start back up sometime before 2015-02-26, 05:21 UTC, and has continued since.

Why is this happening now?  We are still investigating, but it is apparent when looking at the chart of battery voltage over the lifetime of $50SAT/MO-76 that the battery has suffered a sizeable drop in capacity.  If the battery voltage under load is dropping below 2.9V, how is it able to recover back above 3.3 V (the minimum required to enable transmission) and nearly complete another operational cycle?  Moreover, why does it always seem to be able to finish sending an entire RTTY packet before resetting?  In the hopes of better understanding what is happening, I am in the process of re-assembling my “BoxSat” test setup in an effort to reproduce on the ground what is happening in space.  In the meantime, the once-per-minute transmission is actually convenient from telemetry monitoring standpoint, as one no longer has to wait 3 minutes for $50SAT/MO-76 to start transmitting.  So, for any of you who have not heard $50SAT/MO-76, now is the time.  Who knows how long it will continue to operate in this manner?  Who knows how long it will continue to operated at all?  Every time an anomaly has occurred and thought, “this is it – well, it was great while it lasted”, $50SAT/MO-76 has proven me wrong.  I hope that is the case here as well.

The Dropbox has been updated with all the telemetry observations through today (Wednesday, March 4 2015), and can be accessed via the following URL:


I have also uploaded an MP3 file from the daytime pass over EN82 land on Friday, February 27, 2015 starting at 16:59 UTC (11:59 AM local time); it can be accessed via the following URL:


During the recording, I switch back and forth between FM and LSB modes so I can hear the FM Morse beacon as well as the RTTY telemetry.

Please keep the telemetry observations coming, especially now!

73 Michael Kirkhart KD8QBA
$50SAT/MO-76 team

$50SAT was 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. The transmitter power is just 100 mW on 437.505 MHz (+/-9 kHz Doppler shift) FM CW/RTTY. $50SAT uses the low cost Hope RFM22B single chip radio and PICAXE 40X2 processor.

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

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

PocketQubes in SatMagazine

SatMagazine December 2014 PocketQube page 114The December 2014 edition of the free publication SatMagazine features an article on page 114 about PocketQubes by Tom Walkinshaw, Chief Executive Officer of the the Glasgow-based start-up PocketQube Shop.

Download the December 2014 SatMagazine from

SatMagazine Archive

PocketQube Shop featured in The Guardian newspaper http://www.theguardian.com/technology/2014/dec/07/tiny-space-satellite-make-at-home-pocketqube

PocketQube Shop http://www.pocketqubeshop.com/

Happy Birthday, $50SAT/MO-76!

Yaesu handheld and $50SAT 1.5U PocketQube

Yaesu handheld and $50SAT 1.5U PocketQube

Friday, November 21, 2014 marked the one year anniversary of the launch of $50SAT/MO-76 PocketQube satellite.

Michael Kirkhart KD8QBA writes:

Our little creation was launched from Dombarovsky Air Base in Russia at 07:01 UT (which was 2:01 AM here in EN82 land) as one of 33 satellites aboard a Dnepr rocket. It was first heard by Jan, PE0SAT, at 08:46 UT, and by Stuart GW7HPW at 09:17 UT, and has been operating continuously ever since!

The $50SAT/MO-76 Dropbox now contains a snapshot of all the telemetry gathered from launch day through November 21, 2014.

$50SAT/MO-76 continues to operate normally, but the battery capacity has been slowly dropping to the point where it barely registers above 3500 mV when passing over EN82 land during daytime (decending) passes. I have been able to capture telemetry while it passes over Anton’s (ZR6AIC) WebSDR station http://zr6aic.giga.co.za:8902/ which is located in South Africa. During ascending passes, which occur between 20:00 and 21:30 UT, $50SAT/MO-76 has just transitioned from being in sunlight to being in eclipse, and the battery voltage is between 3602 and 3642 mV.

Over the life of $50SAT/MO-76, we have observed the following:
The maximum battery voltage was 3824 mV, while the minimum was 3440 mV
The maximum PCB temperature was 25 degrees C, while the minimum was -29 degrees C
The maximum RFM22 temperature was 29 degrees C, while the minimum was -30 degrees C
The maximum MPPT (solar) power was 312.84 mW
The maximum idle (RFM22 off) current was 3 mA, while the minimum was 2 mA
The maximum receive mode current was 31 mA, while the minimum was 21 mA
The maximum transmit mode current was 88 mA, while the minimum was 77 mA

On December 4, 2013, the folks at NORAD and Celestrak (with help from Mike, DK3WN) were able to identify $50SAT/MO-76 as object 2013-066W. At this time, apogee was at 640 km, and perigee was 595 km. As of November 21, 2014, apogee is at 599 km, and perigee is at 565 km. This means the average altitude has decreased by about 36 km. A spreadsheet, along with a graph of the orbital data is available on the $50SAT/MO-76 Dropbox

While we did not have time to demonstrate this at the AMSAT-NA Space Symposium, we now have a working Arduino/RFM22 based groundstation. It utilizes a slightly modified version of the Sparkfun RFM22 Arduino shield https://www.sparkfun.com/products/11018 Additional information, including photos, marked up schematics, and the Arduino sketches, is available (guess where?) on the $50SAT/MO-76 Dropbox.

In addition to the original, receive-only sketch (S50SAT_receiver), there is a new version (S50SAT-Groundstation) which includes transmit capability, which supports all three open uplink commands. Both versions are capable of receiving all GFSK based packets, including the FEC packets.

I have successfully received $50SAT info and FEC packets from about 1200 km slant range with my groundstation using an Advanced Receiver Research P432VDG LNA http://advancedreceiver.com/page5.html with my homebrew 6 element WA5VJB yagi. The LNA is needed to improve the sensitivity of the RFM22, which is about -99 dBm. Since the RFM22 can only output 20 dBm (100 mW) and the minimum EIRP needed to uplink to $50SAT/MO-76 when it is directly overhead is about 36 dBm (4W), either a 16 dB gain antenna, an external linear amplifier, or both will be needed to successfully uplink.

Speaking of uplinking, no one has completed the $50SAT/MO-76 Uplink Challenge. This challenge is open to any licensed amateur radio operator, and the prize for successful completion is (drum roll…) a certificate of technical achievement, signed by all three of the $50SAT/MO-76 developers.

Our thanks to all who has supported us in this project, including all of you telemetry gathers. Please keep the telemetry coming!

Michael Kirkhart KD8QBA
$50SAT/MO-76 team

$50SAT was 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. The transmitter power is just 100 mW on 437.505 MHz (+/-9 kHz Doppler shift) FM CW/RTTY. $50SAT uses the low cost Hope RFM22B single chip radio and PICAXE 40X2 processor.

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

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

$50SAT / MO-76 six months in space and counting

Yaesu handheld and $50SAT 1.5U PocketQube

Yaesu handheld and $50SAT 1.5U PocketQube

Wednesday, May 21, 2014, marked the six month anniversary of the launch of the tiny $50SAT / MO-76 PocketQube satellite which is just 5x5x7.5 cm and 210 grams.

Michael Kirkhart KD8QBA has released an update on this remarkable satellite:

We have finally completed the first pass cleanup of the telemetry data provided by all of you.  We cannot thank you enough for this data, as it will help us understand how $50SAT/MO-76 has been operating.  Keep it coming!

On the Dropbox, you will find a new directory (Telemetry-analysis/Battery-voltage-2014-06-04) containing our first set of processed data, which serves as an initial investigation into the performance of the on-board Li-ion battery.  Included in this directory is a spreadsheet with all the battery voltage data we have up to now, in both tabular and graphical form; it consists of 1097 individual telemetry observations.  For convenience sake, there is also a copy of the graph in PDF form.  Over the past 6 months, the daily average battery voltage has been dropping.  A best fit line through all the data has a slope of -0.670 mV per day.  The drop, however, has not always been gradual.  For instance, there is a large step change of about -60 mV sometime near February 20, 2014.  We are not sure what happened here.  Anybody out there know what might be going on?

Ignoring the two outliers on the graph, the current low battery voltage is 3521 mV.  This has been observed at least 5 times, including twice by yours truly.  This, of course, occurs when $50SAT/MO-76 happens to be at its lowest temperature, which has been -28 degrees C until yesterday evening, where I observed a temperature of -29 degrees C.  While our depth of discharge on the battery is relatively low (our initial calculations were about 22 mA-hr), it is going through about a -28 degree C to 26 degree C (or possibly higher – this is our highest recorded temperature) and back down to -28 degrees C 14.5 times per day.  Does this violate the conditions of the warranty?

As to whether or not the orbit is decaying, a comparison of the current TLEs with a set from early December 2013 show it is, although by a small amount.

Here are the TLEs from December 4, 2013 (element set 7):
1 39436U 13066W   13337.88841924  .00010097  00000-0  12132-2 0    70
2 39436  97.8019  50.2525 0031655 170.6351 189.5525 14.83797851  1855

Here are the TLEs from June 2, 2014 (element set 223):
1 39436U 13066W   14152.25170112  .00007510  00000-0  78254-3 0  2235
2 39436  97.7787 226.1156 0024706 303.1274  56.7439 14.89857855 28503

$50SAT Boards

$50SAT Boards

The second to last element on line 2 is the mean motion, in units of orbits per day.  From this number, the semi-major axis of the orbit can be computed.  On December 4, 2013, it was 6,995.50 km, and on June 2, 2014, it was 6,976.51 km.  This means the orbit has decayed by about 19 km during this time period.  The orbit has also become slightly less elliptical.  The forth element on line 2 is the eccentricity, which has an implied decimal point in front of it.  On December 4, 2013, it was 0.0031655, and on June 2, 2014, it was 0.0024706.  From this and the computed semi-major axis, the apogee and perigee altitudes are as follows:
December 4, 2013:  apogee = 639.64 km, perigee = 595.36 km
June 2, 2014: apogee = 615.75 km, perigee = 581.27 km

The technical challenge we posed to the amateur community to successfully uplink to $50SAT/MO-76 has yet to be met.  We have since realized some of the documentation, specifically the Silicon Labs Si4432 data sheet, was not clear on at least one of the needed details.  To encourage the amateur radio community to answer our challenge, we will post some information that should be helpful in uplinking to $50SAT/MO-76; look for this sometime in the next few days.

$50SAT/MO-76 has made it onto YouTube!  See a video of the excellent talk on $50SAT/MO-76 given by Howie DeFelice, AB2S, and a video of yours truly operating the AMSAT demo station during a $50SAT/MO-76 pass at the Dayton Hamvention.


Michael Kirkhart
$50SAT/MO-76 team

Talk by Howie DeFelice AB2S at the May 14, 2014, PocketQube workshop
(thanks to Gustavo, LW2DTZ, for taking and posting this video)

$50SAT was 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. The transmitter power is just 100 mW on 437.505 MHz (+/-9 kHz Doppler shift) FM CW/RTTY. $50SAT uses the low cost Hope RFM22B single chip radio and PICAXE 40X2 processor.

Michael Kirkhart KD8QBA operates AMSAT demo station during $50SAT/MO-76 pass Friday, May 16
(thanks to Patrick Stoddard, WD9EWK, AMSAT-NA Vice President for Field Operations, for this video)

$50SAT PocketQube Amateur Radio Challenge

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

$50SAT – Eagle2 – Communications – Release Version V1_2.pdf

Hope RFM22B single chip radio http://www.hoperf.com/rf/fsk_module/RFM22B.htm

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

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