FUNcube – Welcome to 2022

FUNcube-1 - Battery Voltage - Whole Orbit Data

FUNcube-1 – Battery Voltage – Whole Orbit Data

There are presently three FUNcube based missions in orbit – currently all of them have active, linear U/V transponders. The current status of each of these can always be checked on the useful AMSAT-NA status page https://www.amsat.org/status/ and an update on each of them is provided below. Please have FUN using them!

AO73 – FUNcube1. As previously reported AO73 appears to be experiencing some power issues after 8+years in orbit.

The battery is not charging to the same voltage as it did up to early November last year. The spacecraft has experienced many months of continuous sunlight over the past couple of years and this has resulted in high (around +30C) onboard temperatures. This environment may have “cooked” the cells although presently we do not see any direct evidence of this.

We can see that the stable bus voltage indicated at the end of charge is now much lower and depends on the current being taken by the on-board systems. The solar panel currents appear to be similar to those recorded soon after launch. The current best theory is that we are seeing the effect of some increased resistance in the supply circuit between the eps charging circuit and the battery. Although we do not have access to a fully detailed circuit diagram of the EPS we believe that there is an “ideal diode” in this line to prevent discharge of the battery back through the EPS circuitry. We understand that this is actually a MOSFET device and the suspicion is that this may now be showing signs of radiation damage.

So an operational mode has been selected that can be hopefully sustained for some time. From today AO73 is in continuous transponder mode and is available for use 24/7. Low power telemetry is also being transmitted and reports of the data are very welcome via the FUNcube Data Warehouse. Please remember that the uplink frequency varies with on board temperatures. A lower temperature means a higher frequency!

EO88 – Nayif-1. EO88 continues to perform nominally and is switching between high power telemetry for educational outreach when in sunlight and to its U/V transponder mode when in eclipse. It will soon celebrate its 5th birthday in space after launch on 15th February 2017.

JO97 – JY1Sat. JO97 suddenly stopped transmitting telemetry data on May 1st last year. The cause of this anomaly is unknown but fortunately the U/V transponder continues to operate continuously.

Battery voltage and incoming solar current over time - daily average

Battery voltage and incoming solar current over time – daily average

CHESS CubeSat Constellation to carry FUNcube transponders

CHESS CubeSat - Credit EPFL Spacecraft Team

CHESS CubeSat – Credit EPFL Spacecraft Team

In 2020, a project between AMSAT-UK, AMSAT-NL and Swiss universities started with the aim of equipping two Swiss satellites with a linear transponder for amateur radio.

CHESS - Three Unit CubeSat

CHESS – Three Unit CubeSat

With a linear transponder, several QSOs can take place simultaneously. The satellites can be operated in CW/SSB with the simplest equipment. The satellites also include features for classroom demonstrations and experiments. In numerous teleconference discussions, the technical possibilities could be sounded out and the realisation prepared.

The CHESS [Constellation of High Energy Swiss Satellites] project includes two satellites, which will be built simultaneously and later launched as a constellation. Both will provide a linear transponder for amateur radio use. The first satellite will have a nearly circular orbit at an altitude of 400 km. The second will have an elliptical orbit with an altitude of 350×1000 km.

The satellites themselves are a project of the École polytechnique fédérale de Lausanne (EPFL) with support from the Lucerne University of Applied Sciences and Arts (HSLU – Institute of Electrical Engineering IET), the University of Bern, the Valais University of Applied Sciences and Arts (HES-SO), the Haute École Neuchâtel and the Swiss Federal Institute of Technology ETH Zurich. The amateur radio payload is a project of AMSAT-UK/-NL.

On 18 December 2020, the successful system requirements review took place. The project coordination between CHESS and AMSAT lies with the Amateur Radio Association of the Lucerne University of Applied Sciences and Arts – Technology & Architecture, Horw.

The Swiss AMSAT Operators provide information about the CHESS project at https://www.amsat-hb.org/funcube-chess/

EPFL Spacecraft Team https://www.epflspacecraftteam.com/chess-1

CHESS - Three Board Stack

CHESS – Three Board Stack

Raspberry Pi FUNcube satellite telemetry decoder now available

RPi decoder receiving telemetry from JY1Sat in Interactive mode

RPi decoder receiving telemetry from JY1Sat in Interactive mode

The FUNcube Team has announced the availability of FUNcube CubeSat satellite telemetry decoder software for the popular Raspberry Pi computer board.

The original FUNcube telemetry decoder and Dashboard was designed to run on Windows devices and the FUNcube team did publish the telemetry format in accordance with the Amateur Satellite Service traditions and requirements. The Team had planned to opensource the Telemetry Decoder and provide an implementation on Linux, but several new missions after the original FUNcube-1 delayed their plans somewhat.

Late 2019, the Team had the opportunity to develop a low power/low impact ground station, based on Docker containers, for use at the Neumayer III Antarctic base at DP0GVN. This led us to evolve the code such that it would run on a Raspberry Pi.

The Linux implementation is suitable for use on Raspberry Pi versions from 2B+ to 4 and with a FUNcube dongle (Pro or Pro+). The software will tune a dongle to search for and track all three FUNcube compatible spacecraft currently operational. The Telemetry Decoder is configured with five active decoders operating concurrently so it can deal with situations where more than one of the spacecraft are overhead at the same time.

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

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

The decoder and warehouse uploader run as a Docker container for convenience shell scripts have been provided to launch the container in one of two modes:

• “Interactive Mode” is when the Telemetry Decoder operates in the foreground , when FUNcube compatible telemetry is received, the corresponding hex data is displayed on the terminal screen.

• “Background Mode” allows the telemetry decoder to run as a Docker image in the background where it operates much like any other background service on Linux. This mode allows for the automatic restarting of the telemetry decoder after a shutdown or reboot of the Raspberry Pi, therefore making it suitable for a remote deployment situation.

*Both modes, when connected to the internet, will upload the received data to the FUNcube Data Warehouse and the totals displayed on the Ranking Page in the normal manner.

*Uploading to the warehouse requires online registration with the FUNcube Data Warehouse.

All the code for the telemetry decoder, and the scripts to build the Docker images, are now published online under a GPL Open Source License at the FUNcube-Dev GitHub account
https://github.com/funcube-dev

Alternatively, it possible to buy a pre-formatted microSD card for the Pi from the AMSAT-UK shop at https://shop.amsat-uk.org/

Full instructions PDF can be downloaded from https://tinyurl.com/RPi-FUNcube-Decoder

FUNcube Data Warehouse http://warehouse.funcube.org.uk/missions

Brazil: High school students shown amateur radio

Gonçalves Dias School Students

Gonçalves Dias School Students

Brazilian radio amateurs participated in a Science Fair at Gonçalves Dias School, Boa Vista on October 16, 2019.

Paulo PV8DX used basic concepts of physics and geography when explaining amateur radio to the students. As well as theory they there were also practicals involving the students in antenna construction and contacts using the transponder on the amateur radio satellite LAPAN IO-86.

Paulo had asked AMSAT-UK FUNcube team if a special ‘Fitter‘ message could be transmitted from the FUNcube-1 (AO-73) satellite. This was arranged and the message from space was received at the school.

Watch Atividade Escolar – Ham Radio – By PV8DX

Further information on FUNcube-1 ‘Fitter’ messages and how to request one is available at https://funcube.org.uk/ground-segment/fitter-messages/

AMSAT-UK https://twitter.com/AmsatUK

Ideas sought for the next FUNcube satellite

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

In November the FUNcube-1 CubeSat will have been in orbit for 6 years and the FUNcube team are now soliciting suggestions for the next satellite

The team are looking for suggestions for:
• Conformation of the satellite (2U / 3U)
• Orbit (LEO / MEO)
• STEM Outreach
• Amateur Radio Payloads
• Research Payloads

Please email your ideas to:
funcube-next <at> funcube.org.uk

The topic will be discussed during the AMSAT-UK Colloquium on Sunday 13th October 2019 https://amsat-uk.org/colloquium/

If you would like to join the team, please email:
operations <at> funcube.org.uk

Dave, G4DPZ
on behalf of the FUNcube Team

AMSAT-UK payload on ESEO has been activated

Frame received by PQ2HX in Brazil at around 14:17 UTC on April 12, 2019

Frame received by PQ2HX in Brazil at around 14:17 UTC on April 12, 2019

ESA have just released a new mission update for the ESEO Mission. It can be seen at https://www.esa.int/Education/ESEO/ESEO_mission_updates

We are delighted that on April 12, 2019, the BPSK telemetry transmitter, on our payload, was enabled for a period of just over 200 minutes in orbit!

ESEO AMSAT-UK Payload Telemetry Data

ESEO AMSAT-UK Payload Telemetry Data

Although we were not able to announce this activation in advance, more than ten stations around the world successfully received the telemetry on 145.895 MHz and submitted it to the FUNcube Data Warehouse. We are very grateful to them for their support.

Over 50 channels of Real Time and Whole Orbit Data were collected. For example, a number of on-board temperatures are shown in this graph which covers the period from 11:58 to 13:36 UTC

The very last frame received was captured by PQ2HX in Brazil at around 14:17 UTC.

We are keenly awaiting further possibilities to exercise more of the payload as soon as this becomes possible but, in the meantime, is good to know that all the telemetry channels reported nominal values.