AO-73 back in transponder mode

AO-73 back in transponder mode

After a year long period of ‘battery management’, AMSAT-UK and AMSAT-NL have restarted the transponder on AO-73.

After 10 years in orbit, the battery on the satellite has reduced capacity and until recently, has been unable to charge to the nominal 8.3V.
Following some careful battery management, where the transmitter was off during eclipse, the battery status has improved and the transponder has been reactivated.

Although the battery voltage is varying between 8.13 in sunlight and 7.8V at the end of eclipse, this is much improved on the situation earlier in the year.

Low power BPSK telemetry is transmitted on 145.935MHz
The inverting mode U/V transponder input is 435.130 to 435.150MHz
The transponder downlink is 145.970 to 145.950MHz

At the moment the satellite has a high spin rate of apx. 30 rpm and if you’ve not used AO-73 before, the downlink can be Doppler tracked successfully, but the input on 70cms is best tuned manually due to temperature drift of the receiver.

73

David G0MRF – AMSAT-UK

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ITU WRC-23: 1240-1300 MHz

ITU WRC-23: 1240-1300 MHz

IARU RNSS GraphicIARU have provided an update on the outcome of ITU WRC-23 Agenda Item 9.1B concerning the Amateur and Amateur Satellite Service allocations in 1240-1300 MHz:

“During the WRC-23 deliberations, strong positions were expressed by all the parties involved. The result is a well-supported compromise for a footnote in the Radio Regulations regarding amateur and amateur satellite service operation in the 1240–1300 MHz range. The footnote reminds administrations and amateurs of the need to protect the primary RNSS from interference and provides guidance to administrations to allow both services to continue to operate in this portion of the spectrum. The compromise was formally adopted by the Conference Plenary on December 8 and is not subject to further consideration during the final week of the WRC. The IARU team continues its work on other WRC issues including the development of agendas for future conferences.

IARU President Tim Ellam, VE6SH, noted “This is a very good result for the amateur services. The decision reached at WRC-23 on this agenda item makes no change to the table of allocations nor incorporates by reference M.2164 into the Radio Regulations. The addition of a footnote that provides guidance to administrations in the event of interference to the RNSS is a good regulatory outcome for amateurs and the primary users of this band.”

The WRC also agreed to suppress the Resolution 774 which closes the issue and satisfies the agenda item.”

Read the full IARU statement at https://www.iaru.org/recommendation-on-ai-9-1b-approved-at-wrc-23/

Download ITU‑R Report M.2532 https://www.iaru-r1.org/wp-content/uploads/2023/11/R-REP-M.2532-2023-PDF-E.pdf

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Happy 10th Birthday FUNcube-1 (AO-73)

Happy 10th Birthday FUNcube-1 (AO-73)

November 21, 2023, marks the tenth birthday of our very first CubeSat mission, FUNcube-1 (AO-73).

A very short time after the launch from Yasny in Russia and within a few minutes from deployment, the very first frame of data from the low power transmitter on board, was detected and decoded by ZS1LS in South Africa. He was able to relay the data over the internet from his Dashboard to the Data Warehouse and the numbers, appeared, as if by magic, at the launch party being held at the RSGB National Radio Centre at Bletchley Park.

After a very brief check out, the FUNcube team were able to switch the transmitter to full power, again at the very first attempt, and were quite amazed at the strength of the signal from the 300mW transmitter on 145.935 MHz. The transponder was then switched on and successfully tested, the first contact was between G6LVB and M5AKA who were both operating from the Bletchley Park car park.

The team finished the day with a request to AMSAT-NA for an Oscar number and were delighted to receive the AO73 Oscar 73 designation!

Since then, FUNcube-1, with a launch mass of less than 1kg, has operated continuously with only a very few interruptions. In excess of 53,500 orbits, 1.3 billion miles travelled, 61 million telemetry data packets transmitted, and with more than 10.9 million unique data packets downloaded and stored in the Data Warehouse.

The FUNcube team still receive many requests for Fitter message uploads for school events…please contact us by email to operations@funcube.org.uk giving us at least two weeks notice.

The FUNcube team continue to be very grateful to all the many stations around the world that continue to upload the telemetry that they receive to our Data Warehouse. They really need this data to provide a continuous resource for educational outreach.

FUNcube Data Warehouse and the Dashboard software
https://funcube.org.uk/working-documents/funcube-telemetry-dashboard/

FUNcube email group https://groups.io/g/FUNcube

FUNcube Website http://www.funcube.org.uk/

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EISAT-1 CubeSat

EISAT-1 CubeSat

EIRSAT-1 is expected to launch on a Space X Falcon 9 rocket from the Vandenberg Air Force Base in California, USA, on November 29, 2023. It will have a downlink on the IARU coordinated frequency of 437.100 MHz, see https://iaru.amsat-uk.org/finished_detail.php?serialnum=639

https://www.esa.int/Education/CubeSats_-_Fly_Your_Satellite/Ireland_s_first_satellite_on_its_way_to_launch

Follow the EIRSAT-1 team on X at https://twitter.com/EIRSAT1

EIRSAT-1 website https://www.eirsat1.ie/

 

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