Tag Archives: FUNcube-1

Nov 22 2022

FUNcube-1 (AO73) Now celebrating nine years in orbit!

FUNcube-1 (AO73) Battery Voltage Telemetry Nov 21, 2022

FUNcube-1 (AO73) Battery Voltage Telemetry Nov 21, 2022

Another year has passed and FUNcube 1 has continued to operate from its orbit around 600km above the earth. To start with some statistics. The spacecraft creates and downlinks data in frames that run for two minute periods. It has now transmitted more that 16 million of these frames or “Sequence Numbers”. Another big statistic is that more than 10 million data packets have been received by stations that have forwarded them to our Data Warehouse.

You can see the leading ground stations here http://warehouse.funcube.org.uk/ui/fc1-fm/satellite_ranking – special congratulations to those at the top scorers…many of them have individually forwarded more than 1 million packets. Thanks to all contributors around the world. Having this network of ground stations has enabled us to easily monitor the status of the spacecraft easily.

Back here on earth, as mentioned, we have continued to monitor the health of the spacecraft as these illumination levels and spin/tumble rates have changed over the months.

Whilst mentioning big numbers, we are now approaching 48500 orbits and this equates to a distance travelled of 2174091840000000000000000000 fermis since launch. That’s 2.1 ronnafermis. Yes these are genuine SI Units of Measure and are equivalent to 14.16 AU or almost half way to Neptune.

After some time in full sun, the spacecraft is now experiencing “normal” eclipse periods of around 25 minutes each orbit. This will reduce the on board temperatures and may influence the tumble rate which has been between 2 and 5 seconds for some time. The is quite fast and is not helping telemetry reception with our 5 second data frame mentioned above.

The present operational schedule is for high power telemetry when in sunlight and receive only when in eclipse. This seems to suit the EPS quite well and the battery bus voltages have been quite stable.

At least that was correct until early morning on Friday 11th November when the indicated bus voltage appeared to “drop off a cliff” over the period of just four orbits. Further analysis showed that the 3.3V bus consumption had suddenly jumped four times normal. As can be seen by the graph above this problem then disappeared just as suddenly and the bus voltage recovered quite quickly. Investigations are continuing!

Please keep the telemetry reports coming in and let us know if you would like a Fitter message uploaded for any educational or outreach events.

Jun 13 2022

FUNcube-1 / AO73 Update

The Queen's Platinum Jubilee 2022Many will be aware that FUNcube-1 has been transmitting a special Fitter message to commemorate her Majesty the Queen’s Platinum Jubilee earlier this month.

Everyone who receives this message and uploads it to the Data Warehouse using the Dashboard can generate a certificate to remember this historic event. The special message includes a link to a website that has the full instructions. It is intended to keep this message active until the end of June.

The spacecraft’s orbit continues to run near the sun’s terminator and this is resulting in less than optimal solar power generation. The battery bus voltage is now centering around 7.45 volts rather than the 8+ volts that we have seen for many years. We believe that this reduced voltage level may be due to a combination of factors, illumination levels, battery and/or solar panel degradation or, possibly, gradual changes in some component values within the EPS. It is also possible that the high spin/tumble rates that we experienced over the recent months may be involved. Our thanks to to Colin VK5HI and his team for continuing to keep track of this issue for us.

Operators may have noticed that the spacecraft is now in high power telemetry mode when in sunlight and in receive only mode during eclipse. Although the transponder is not currently active, with the rapid fading presently being experienced on the downlink, the high power telemetry setting will assist listeners to decode the data more easily.

We continue to be extremely grateful to all those stations who continue to contribute their data to the FUNcube data warehouse. The information you are providing is invaluable to the FUNcube to team and will greatly assist us in managing the spacecraft through its “middle age” after more than eight years in space!

Jun 1 2022

AO-73/FUNcube-1 Fitter Message for The Queen’s 70th Jubilee Celebration

The Queen's Platinum Jubilee 2022In June 2022, Her Majesty The Queen becomes the first British Monarch to celebrate a Platinum Jubilee after 70 years of service.

AMSAT-UK has decided to send a special Platinum Jubilee greetings message via FUNcube-1 (AO-73). Anyone who receives this message and uploads it to the Data Warehouse using the Dashboard can generate a certificate to remember this historic event.

AO-73/FUNcube-1 is transmitting the Jubilee Fitter message on the BPSK Telemetry beacon which has a nominal frequency of 145.935 MHz +/ Doppler.

The AO-73/FUNcube-1 Dashboard App can be downloaded from
https://funcube.org.uk/working-documents/funcube-telemetry-dashboard/

Data Warehouse http://data.amsat-uk.org/missions

Online tracking of AO-73 https://www.n2yo.com/satellite/?s=39444

Nov 21 2021

FUNcube-1 (AO73) Celebrating eight years in orbit!

FUNcube-1 Telemetry as at Nov 21, 2021

FUNcube-1 Telemetry as at Nov 21, 2021

November 21, 2021, marks the eighth birthday of the FUNcube-1 CubeSat. Remarkably the tiny spacecraft, launched from Russia on November 21, 2013, continues to work well having travelled more than a billion kilometres in space.

During the past couple of months, the spacecraft’s orbits have been running just along the edge of the terminator. Initially we had effectively full sun with no eclipses but at the beginning of this month it appears that the solar panels were not receiving enough solar radiation to keep the battery fully charged.

FUNcube-1 was transmitting continuous high-power telemetry and was therefore consuming maximum power. The screenshot above is from the AMSAT-UK/BATC groundstation at Goonhilly Earth Station. The FUNcube Dashboard shows the rapid decline in the bus voltage from an already below normal 8.0V down to 7.8V. The spacecraft was switched to “safe” mode on the afternoon of November 18th. This reduced to total power consumption by almost 50% and, as can been seen, the spacecraft is again in a happy “power positive” situation.

Although safe mode provides less than 20mW of downlink RF, it is remarkable how many stations are still receiving and decoding the 1k2 BPSK telemetry. This is a good point at which to say a massive thank you to the many many stations around the world who, even after eight years, are continuing to submit their data to the FUNcube Data Warehouse. It really is valuable to the team and has really helped us to understand what is going on up there!

We will continue to monitor the telemetry over the next few weeks and plan to return FUNcube-1 to nominal autonomous operation, with the transponder on when the spacecraft is in eclipse, as soon as possible.

Interestingly, it appears that we will not be having any more “full sunlight” periods for the foreseeable future., however those that we have experienced have provided some good data on how hot a 1U CubeSat can become in such circumstances!

Sep 15 2021

FUNcube-1 (AO73) returns to full sunlight and continuous telemetry mode

AO-73 (FUNcube-1) - Image credit Wouter Weggelaar PA3WEG

AO-73 (FUNcube-1) – Image credit Wouter Weggelaar PA3WEG

After a few months of normal eclipse periods, FUNcube-1 (AO73) will, next week, re-enter full sunlight from next week for a period of approximately two months.

As we have been in continuous transponder mode for some time now, we have decided that, during this sunlight period, FUNcube-1 should operate in continuous high power telemetry mode. The change will be made within the next few days.

FUNcube-1 has now been in orbit for almost eight years and the telemetry indicates that all systems, including the battery and solar panels appear to operating as well now as they did immediately after launch!

Jun 1 2020

FUNcube-1 in continuous transponder mode

AO-73 (FUNcube-1) – Image credit Wouter Weggelaar PA3WEG

After some eight months in continuous sunlight, FUNcube-1 has now started to see some eclipses during each orbit.

The telemetry received has shown that the spacecraft continued to function perfectly during this period and the on board temperatures did not reach excessively high levels.

After this became clear, our next concern was the battery. Having been kept fully charged for this period, would it actually hold a charge and do its job when in eclipse?

After three weeks of increasing eclipse periods we can now see that indeed the Li battery appears to be ok and the bus voltage has not yet dropped below 8.1 volts.

So today we have changed the operating mode from high power telemetry educational mode to continuous amateur mode withe the transponder ON. The telemetry continues to be available, albeit at low power.

We will, of course, continue to carefully monitor the data but are planning to leave the spacecraft in this mode for at least the next week. Please enjoy using it!