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ARISS Europe to Perform Special Digital SSTV Experiment

Amateur Radio on the International Space Station (ARISS) is planning for a special SSTV experiment. ARISS is the group that puts together special amateur radio contacts between students around the globe and crew members with ham radio licenses on the International Space Station (ISS) and develops and operates the amateur radio equipment on ISS.

As part of its ARISS 2.0 initiative, the ARISS International team is expanding its educational and life-long learning opportunities for youth and ham radio operators around the world. ARISS Slow Scan Television (SSTV), which is the transmission of images from ISS using amateur radio, is a very popular ARISS mode of operation. To expand ARISS SSTV capabilities, the ARISS Europe and ARISS USA teams plan to perform special SSTV Experiments using a new SSTV digital coding scheme. For the signal reception, the software “KG-STV” is required, as available on internet.

We kindly request that the amateur radio community refrain from the use of the voice repeater thin this SSTV experiment on February 20, 2022, over Europe.

This is a unique and official ARISS experiment. We kindly request keeping the voice repeater uplink free from other voice transmissions during the experiment time period. Also note that ARISS is temporarily employing the voice repeater to expedite these experiments and make a more permanent, more expansive SSTV capability fully operational on other downlink frequencies.

The first experiment in the series will utilize ARISS approved ground stations in Europe that will transmit these digital SSTV signals. These will be available for all in the ISS footprint when SSTV transmissions occur. The first SSTV experiment is planned for February 20, 2022, between 05:10 UTC and 12:00 UTC for five ISS passes over Europe. Please be aware that this event depends on ARISS IORS radio availabilities and ISS crew support, so last-minute changes may occur.

To promote quick experimental SSTV investigations—to learn and improve–the ARISS team will employ the ISS Kenwood radio in its cross-band repeater mode. The crossband repeater operates on a downlink of 437.800 MHz. Each transmission sequence will consist of 1:40 minute transmission, followed by 1:20 minute pause and will be repeated several times within an ISS pass over Europe.

The used modulation is MSK w/o error correction. For the decoding of the 320 x 240 px image, the software KG-STV is required. The KG-STV software can be downloaded from the following link:
http://amsat-nl.org/wordpress/wp-content/uploads/2022/02/kgstv_ISS.zip

The ZIP file contains the KG-STV program, an installation and setup manual, some images and MP3 audio samples for your first tests as well as links for additional technical information about the KG-STV use.

The members of the ham radio community youth and the public are invited to receive and decode these special SSTV signals.

Experiment reports are welcome and should be uploaded to “sstvtest@amsat-on.be”

More information will be available on the AMSAT-NL.org web page:
https://amsat-nl.org/?page_id=568

(for the team: Oliver Amend, DG6BCE)

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m5aka

AMSAT-UK

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Nayif-1 (EO-88) Celebrates a 5th Birthday in orbit!

Wouter PA3WEG at the groundstation waiting for the first NAYIF-1 signals

Nayif-1 (EO-88) was launched at 03:58 UTC on February 15, 2017, on a PSLV launcher from India. It was part of a world record launch as the C37 flight carried 104 spacecraft into orbit.

Nayif-1 team members after completion of the assembly and integration of the CubeSat

The transmitter was autonomously activated around 04:47 UTC and the first signals were received and decoded a few minutes later by KB6LTY and within a few hours more than 250 stations around the world had submitted telemetry reports to the Data Warehouse.

After more than 27500 orbits of the earth, the spacecraft continues to function nominally. It switches between high power telemetry when in daylight to low power telemetry and transponder when in eclipse.

The mission was developed by the Mohammed bin Rashid Space Centre (MBRSC) and American University of Sharjah (AUS). The UAE’s first Nanosatellite was developed by Emirati engineering students from AUS under the supervision of a team of engineers and specialists from MBRSC within the framework of a partnership between the two entities, aiming to provide hands-on experience to engineering students on satellite manufacturing.

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m5aka

AMSAT-UK

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ISS SSTV Feb 7-8 145.800 MHz FM

ISS SSTV MAI-75 image 9/12 received by Chertsey Radio Club on Baofeng handheld

Russian cosmonauts on the International Space Station (ISS) are planning to transmit Slow Scan TV (SSTV) images on 145.800 MHz FM probably using the SSTV mode PD-120.

The transmissions are part of the Moscow Aviation Institute SSTV experiment (MAI-75) and will be made from the amateur radio station RS0ISS in the Russian ISS Service module (Zvezda) using a Kenwood TM-D710E transceiver.

Feb 7: 08:35 – 15:05 GMT*
Feb 8: 10:40 – 14:30 GMT*

*Dates and times may be subject to change.

The signal should be receivable 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.

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

ARISS SSTV Blog https://ariss-sstv.blogspot.com/

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

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m5aka

AMSAT-UK

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EASAT-2 and HADES Update

AMSAT-EA Mission Manager Felix EA4GQS provides an update on the status of the EASAT-2 and HADES satellites launched on January 13.

On the AMSAT Bulletin Board he writes:

We confirm the reception of both EASAT-2 and HADES, as well as the decoding of telemetry and the FM recorded voice beacon with the callsign AM5SAT of the first one. EASAT-2 appears to be working well except for the deployment of the antennas, something that apparently has not yet occurred and causes weak signals. However, the AMSAT-EA team confirms that, based on the reception of FSK, CW, the FM voice beacon and the telemetry data that has been decoded, it can be said that the satellite is working perfectly. In the event of low battery or system malfunction, the on-board computer would not transmit CW messages or the voice beacon-callsign, as it would be in a ‘safe’ state with only fast and slow telemetry transmissions.

These signals that have been able to confirm the operation of both satellites were received by Dr. Daniel Estévez EA4GPZ at 18:07 UTC on Saturday, January 15, using two antennas from the Allen Telescope Array. The TLEs used were obtained from the radio amateur community, with Doppler observations from the Delfi-PQ satellite, deployed together with EASAT-2 and Hades.

TLEs used were these ones:
https://github.com/AMSAT-EA/easat2-tle-lottery/blob/main/satnogs-2022-01-16-DELFI-PQ.tle

Daniel EA4GPZ performed a preliminary analysis using just one polarization of one of the satellite dishes. EASAT-2 has been detected with a relatively strong signal, close to the Delfi-PQ signal, obtaining said recorded voice FM beacon transmissions and FSK, FSK-CW at 50 baud.

The CW beacon clearly shows the message: VVV AM5SAT SOL Y PLAYA, which is one of several that both satellites emit, although the callsign AM5SAT confirms that it is EASAT-2.

In the recording made by Daniel EA4GPZ there is also a faint trace confirmed to be from Hades and stronger packets probably from the IRIS-A satellite.

HADES, like EASAT-2, is transmitting weak signals, weaker than the ones of EASAT-2, most likely because the on-board computer has not yet managed to deploy the antennas either, although it will continue trying regularly. The reason the signals are suspected to be weaker at Hades is that the antennas are more tightly folded than those of EASAT-2. In any case, this is great news, since the transmission pattern confirms the proper functioning of the satellite. In the observations you can see the FSK tones with a deviation of about 5 kHz interspersed with the FM carrier corresponding to the voice beacon of the satellite, which has callsign AM6SAT. The AMSAT-EA team is working to try to decode the telemetry signals and obtain more detailed information on the state of the satellite.

We kindly ask you, if you have very high gain antennas, to try to receive them, specially Hades. If we could decode telemetry it would be very helpful for us.

Until antennas are deployed it will be very difficult to use their repeaters or to receive any SSTV camera images from Hades, but we hope that this will happen sooner or later, at least because even if the computer doesn’t succeed applying heat to the resistor where the thread is attached, with time, the thread should break due to the space environment conditions.

Details of the decoded telemetry and voice, as well as more details in:
https://www.amsat-ea.org/ (Texts are in Spanish)

And in the following Twitter threads:

EASAT-2 transmissions:
https://twitter.com/ea4gpz/status/1482457631566487553

EASAT-2 decodings by Gabriel Otero:
https://twitter.com/gaoterop/status/1482758196037050382

HADES transmissions:
https://twitter.com/ea4gpz/status/1482696274797338625

Thanks a lot and 73,

Felix EA4GQS – AMSAT EA Mission manager

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m5aka

AMSAT-UK

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IARU-R1: 23cm Band and RNSS – Compromises need to be found

RNSS – Credit IARU Region 1

The Chair of IARU Region 1 Spectrum Affairs, Barry Lewis G4SJH, reports on the work being done in defending the interests of the Amateur Services in the 1240-1300 MHz band.

On the IARU Region 1 site he writes:

As we head into 2022 the ITU‑R and CEPT work considering the 23cm band and coexistence with the RNSS systems (GALILEO, COMPASS, GLONASS, GPS…) will continue so where have we got to and where is it heading?

The IARU has provided extensive information regarding the amateur and amateur satellite service applications in the band 1240 – 1300MHz as well as operational characteristics and data indicating the density of active transmitting stations and the busiest periods when these are most likely to be operational. Using this data, one CEPT administration has provided an extensive set of propagation model predictions for a number of amateur operating scenario assumptions (including satellite working and EME operation) that predict an “interfered area” over which an amateur transmissions may be received by a RNSS receiver at levels exceeding a defined protection level. Another ITU‑R member administration contributed a smaller set of predictions using the same model. The received RNSS interference level that the RNSS can tolerate (receiver protection level) is based on ITU‑R recommended criteria and depends on whether narrowband or wideband interfering signals are being transmitted.

The propagation model predicts that an interfered area can extend out to several tens of km (depending on the scenario) but at the extremes of the area, the time probability of exceeding the protection level is very low (1%) and for only 50% of locations. The model can only assume a full power continuous transmission.

In addition much attention has been paid to documenting an interference case recorded in Italy between an Italian 23cm band repeater and GALILEO receivers at the nearby European Commission Joint Research Centre in Ispra where work is undertaken to develop and test GALILEO system applications. The impact of traffic through this very local repeater (12.5km distant) on three different GALILEO receivers has been documented. This work suggests that whilst RNSS receiver bandwidth can have a part to play in enabling coexistence, beyond that nothing has been reported that could help develop any coexistence criteria. Nothing is reported about the mode of failure in the receivers beyond degradation on C/N.

This one case is often cited as the “proof” that interference can occur.

At present the conclusions from this work are being developed (in ITU‑R and CEPT) and IARU work continues to ensure these results are put into a real world context to understand what they imply with respect to successful coexistence.

Amateur transmissions virtually anywhere in the band will be co-frequency with the RNSS receivers from one system or another. It is therefore obvious that any RNSS receiver will be open to any co-frequency amateur transmission and amateur operators have no way of knowing where or when a RNSS service user is active. Therefore IARU has expressed a view that for successful coexistence guidance to be developed, some compromises will need be necessary.

As we move through the work in 2022 we need these compromises will become apparent so that the amateur community can know how to respond appropriately in a way that can allow our diverse set of applications to continue to develop whilst minimising any potential disruption to RNSS services. It is anticipated that the international views on the ITU‑R studies will need to stabilise by the middle of this this year in order to meet the timetable for the WRC-23 preparatory work. These views will likely propose technical and operational measures to be applied to the amateur and amateur satellite services that could be formalised in the Radio Regulations.

As the study activities work towards conclusions it is vital that the national societies engage with their national amateur radio regulators to ensure they understand and hear about the importance of this band for the amateur radio community.

Source IARU-R1
https://www.iaru-r1.org/2022/23cm-band-and-rnss-compromises-need-to-be-found/

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m5aka

AMSAT-UK

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