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FUNcube – Welcome to 2022

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

Get The Details…

m5aka

AMSAT-UK

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XW-3 (CAS-9) Satellite Launch December 26

XW-3 (CAS-9) satellite

The CAMSAT XW-3 (CAS-9) satellite carrying a 145/435 linear transponder has been installed on the CZ-4C Y39 launch vehicle at the Taiyuan Satellite Launch Center. The launch is scheduled for 03:11:31 GMT on December 26.

XW-3(CAS-9) satellite will be piggybacked on the rocket with primary payload ZY-1(02E) satellite. The satellite orbit is a circular sun-synchronous orbit with an altitude of 770.1 kilometers and an inclination of 98.58 degrees, the running cycle is 100.14 minutes.

The functions of XW-3(CAS-9) satellite include UHF CW telemetry beacon, GMSK telemetry data transmission, V/U mode linear transponder, a visible light band space camera and an experimental thermoelectric generator for high school students.

Deployment from the launcher will take place at  at 98.858° east longitude and 28.413° north latitude at 03:35:58 GMT, location close to Western Australia. Radio amateurs should receive CW beacon and GMSK telemetry signals approximately 38 seconds after the satellite is separated from the launch vehicle, and then the linear transponder will be put into use after approximately 49 seconds.

Download the XW-3（CAS-9) Amateur Radio Satellite User’s Manual V1.0

Download the XW-3 (CAS-9) Amateur Radio Satellite Launch Time Sequence

Download the XW-3 (CAS-9) Two-Line Orbital Element file

Get The Details…

m5aka

AMSAT-UK

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CAS-9 / XW3 to launch December 25

XW-3 (CAS-9) satellite

The CAMSAT XW-3 (CAS-9) satellite carrying a 145/435 linear transponder has been installed on the CZ-4C Y39 launch vehicle at the Taiyuan Satellite Launch Center, launch is expected on December 25.

XW-3(CAS-9) satellite will be piggybacked on the rocket with primary payload ZY-1(02E) satellite. The satellite orbit is a circular sun-synchronous orbit with an altitude of 770.1 kilometers and an inclination of 98.58 degrees, the running cycle is 100.14 minutes.

The functions of XW-3(CAS-9) satellite include UHF CW telemetry beacon, GMSK telemetry data transmission, V/U mode linear transponder, a visible light band space camera and an experimental thermoelectric generator for high school students.

Download the XW-3（CAS-9) Amateur Radio Satellite User’s Manual V1.0

Get The Details…

m5aka

AMSAT-UK

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ISS SSTV in late December

The ARISS team will be supporting Slow Scan TV (SSTV) operations from the International Space Station during the period of December 26-31.

The images will be related to lunar exploration. The transmissions should be available worldwide on 145.800 MHz FM. The planned SSTV mode is PD 120.

Planned start and stop times are currently listed as:
Start – Dec 26 about 18:25 GMT
Stop – Dec 31 about 17:05 GMT

The signal should be receivable even on a handheld with a 1/4 wave whip. If your rig has selectable FM filters try the wider filter for 25 kHz channel spacing.

Check the ARISS SSTV blog for the latest information http://ariss-sstv.blogspot.com/

ARISS SSTV Award https://ariss.pzk.org.pl/sstv/

The signal from the ISS should be receivable outdoors on a handheld with a 1/4 wave whip although tracking the ISS with a small handheld beam will give better results. If your rig has selectable FM filters try the wider filter for 25 kHz channel spacing.

You can get predictions for the ISS pass times at https://www.amsat.org/track/

Useful SSTV info and links https://amsat-uk.org/beginners/iss-sstv/

Get The Details…

m5aka

AMSAT-UK

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

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!

Get The Details…

m5aka

AMSAT-UK

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