Posts by DB2OS

Hi all,

the time between the transmissions has been reduced..

I have just received 3 pics in one pass (one double) and added them to my posting above..

73s Peter

here my received files:

https://network.satnogs.org/ob…w1&results=d1&start=&end=

unfortunately the SatNOGS SSTV decoder does not work well, but there is a trick:

1) Install SOX on your Windows computer

http://sox.sourceforge.net/

2) Install MMSSTV

https://hamsoft.ca/pages/mmsstv.php

3) on the SatNOGS Observation go to Downloads and right-click on the Audio button to save the .OGG audio file

4) Convert .ogg to .wav for MMSSTV

in the directory (using CMD for example) you can use the following command line (or write a batch file) to convert the OGG-File to Mono and samplerate 11.025 kHz. Rename the files accordingly..

"C:\Program Files (x86)\sox-14-4-2\sox.exe" in.ogg -c 1 -r 11025 out.wav

5) Open MMSTV and load the above out.wav file in the play dialog box. You might first enter *.wav in the search box.

6) Voila !! This way you can view the SSTV transmissions from around the world...

rock solid with Anjo-Eggbeater:

73s Peter

ARISS News Release No. 20-10

Dave Jordan, AA4KN

ARISS PR

aa4kn@amsat.org

FOR IMMEDIATE RELEASE

SSTV Event Scheduled for early August

August 03, 2020 — A Slow Scan TV (SSTV) event is scheduled from the International Space Station (ISS) for early August. Date and times for the event are Aug 4 (12:25-18:10 UTC) for setup and operation and Aug 5 (08:15-18:25 UTC) for operation and close down. This is an MAI-75 experiment activity developed by the Moscow Aviation Institute.

Images will be downlinked at 145.8 MHz and the expected SSTV mode of operation is PD 120. Radio enthusiasts participating in the event can post and view images on the ARISS SSTV Gallery at https://www.spaceflightsoftware.com/ARISS_SSTV/ .

About ARISS:

Amateur Radio on the International Space Station (ARISS) is a cooperative venture of international amateur radio societies and the space agencies that support the International Space Station (ISS). In the United States, sponsors are the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL), the ISS National Lab and NASA’s Space Communications and Navigation program. The primary goal of ARISS is to promote exploration of science, technology, engineering, the arts, and mathematics topics by organizing scheduled contacts via amateur radio between crew members aboard the ISS and students. Before and during these radio contacts, students, educators, parents, and communities learn about space, space technologies, and amateur radio. For more information, see www.ariss.org.

Media Contact:

Dave Jordan, AA4KN

ARISS PR

This morning the DATV-Team (Thomas&Stefan) successfully performed remote-update of the Firmware and the DATV Beacon is back to normal.

As an additional countermeasure a SW watchdog will perform a reboot every 24 hours. During the reboot the DATV Beacon will stop for a short period.

Hi Enzo,

the DATV Beacon is currently transmitting no valid data..

See: QO-100 Beacon, bad TS

73s Peter

Today the DATV beacon stopped completely.

After a hardware reset was performed the DATV beacon was back with nominal level, but with garbage TS.

A second reset procedure also did not cure the problem.

For tomorrow at 08:00 UTC we have planned a remote maintenance session for further analysis by our DATV-Team, including Firmware update.

And please remember, the A71A DATV Beacon frequency is *exclusively* reserved for our groundstations and should not be used even if the Beacon is Off; Thank you!

Hello Jean-Pierre,

I completely understand that of course.. Sorry for any inconvenience this may cause on your side..

I hope it can be fixed soon.

73s Peter

We understand your impatience and be assured that we are not satisfied with the current situation either.

Unfortunately, we could not foresee that the reduction of the symbol rate and lower bandwidth of the DATV beacon, demanded by many users, would lead to such problems.

4 months ago nobody could have foreseen the effects of COVID-19.

We have people in our team who are affected by this both professionally and privately! Since all people involved in the project volunteer their working time to AMSAT-DL, this does not remain without effects.

The described problems of the DATV beacon are well known, but there is no short-term solution either, as all planned trips to Qatar have been cancelled for this year due to Corona.

Our HW/SW developers have localized the problem in an encoder chip. This is a bug that appears especially with the current parameters and lower symbol rates. Attempts to fix this by a workaround in the software unfortunately did not lead to the desired success.

Therefore we plan to replace the DATV transmitter in Qatar with new hardware. Due to Corona this will be possible next year at the earliest.

Last month we had already planned a Firmware update, which uses a watchdog to restart the hardware every 24 hours. This should then eliminate or reduce the accumulating timing errors.

The remote access to our hardware in the control center at Es'hailSat requires some arrangements and coordination. We hope that the new firmware can be loaded as soon as possible.

73s Peter DB2OS, AMSAT-DL QO-100 Team

MARS 2020 is back in "normal mode" running robust 60000Bd, BPSK Turbo 1/6 code with frame length 8920bits.

CCSDS frames contain following text in the padding for idle frames:

Credit: @r00t.cz

Just at this moment the DSN station in Madrid took over from Canberra and is now in control of Mars 2020. The S/C locked on the Uplink signal... Let's see what happens over night..

Well... the Media...

MARS 2020 was extremely strong after the S/C TX was turned on, when still very close to earth.

Signals were so strong, that Canberra had to use a 20 dB attenuator and the receivers were still over-saturated. It took an hour before the spacecraft was at further distance and receiver was able to have stable lock,

Obviously the spacecraft switched to SafeMode and due to the low telemetry rate first analysis of telemetry takes a while. Meanwhile they switched to 10 kb/sec.

Just a few minutes ago the DSN Groundstation in Madrid also locked on at 6° Elevation and is receiving data.

Remember, in space everything goes very slowly and there is no need to hurry or panic.. So you take the time and carefully analyze the data before you do something you might later regret..

So, they can communicate with the spacecraft, can send commands and receive telemetry.

The "safe mode" could be caused by a small glitch or very tight tolerances.

At this point we should not worry too much..

Yes, we are also currently receiving the signals with our 20m Dish in Bochum, which is remotely operated by Achim DH2VA at this moment.

73s Peter

und hier noch einmal zum Anhören..

https://network.satnogs.org/observations/2618844/

alle Beobachter:

https://network.satnogs.org/ob…40&end=2020-07-30+16%3A53

SPACECRAFT SEPARATION! T+plus 57 minutes, 45 seconds. The Atlas V rocket has deployed NASA's Mars 2020 mission featuring the Perseverance rover on a 7-month, 300-million-mile (483 million km) trek to the red planet.

A camera on the Centaur upper stage sees the Mars 2020 spacecraft moving away from the rocket after separation (credit: ULA)

Successful AOS and telemetry from Mars 2020 at DSN antennas in Canberra and Goldstone.

https://eyes.nasa.gov/dsn/dsn.html

Bochum is standby for local AOS of Mars 2020 at 1930h UTC.

Quote from DO4BMW

Ach du auch mit an board :-))

Die Anschnallzeichen sind gerade ausgegangen, ich sitze auf Platz 1A, komm mich mal besuchen!

now Live

Chinese Mars probe Tianwen-1 successfully received by AMSAT-DL in Bochum

https://amsat-dl.org/chinese-m…lly-received-by-amsat-dl/

Quote from DL1GNM

Hey Peter,

Don't fly away !

You're right, I know a few other people on our planet Earth, who would be better sent to Mars first, or better just pass Mars.

I'll be back!

and yes, I'm already on-board

and finally for 2020:

The Mars 2020 Mission (Perseverance Rover) launch is plannend for July 30, 2020 at 11:50 UTC (4:50 a.m. PDT/ 7:50 a.m. EDT).

https://mars.nasa.gov/mars2020/

https://www.jpl.nasa.gov/news/news.php?feature=7713

Launch broadcast and replay: