Dozens of messages were posted to the Amsat-bb after the news of the amateur radio satellite AO-51‘s end of mission was received. Many remembered their contacts, several thanked the Operating Team. Many noted that AO-51 was the satellite that brought them into this part of our hobby. Continue reading
It is with a heavy heart I report that AO-51 has ceased transmission and is not responding to commands. The last telemetry data indicated that the third of six batteries was approaching failure to short, and observations indicate the voltage from three cells is insufficient to power the UHF transmitters. The IHU may continue to be operative. Initial tests with the S band transmitter were also not positive, although more attempts are in order. We have tried leaving the satellite in an expected state where if voltages climb high enough, the 435.150 transmitter may possibly be heard.
The command team will regularly attempt communications with the satellite over the coming months (and years). There is always the possibility that a cell will open and we could once again talk to our friend while illuminated. Thanks to all who helped fund, design, build, launch, command, and operate AO-51. It’s 7 year mission has been extraordinary. Please support AMSAT’s Fox-1 project, and other AMSAT projects worldwide with your time and money.
For the AO-51 Command Team,
73, Drew KO4MA
AMSAT-NA VP Operations
AMSAT-NA VP Operations Drew Glasbrenner KO4MA reports on Friday’s IHU crash on the Amateur Radio satellite AO-51.
Sometime between 1815 and 1945Z November 25, AO-51’s IHU crashed. This happened after a few days of intermittent and unpredictable operation.
Mark N8MH and I reset the satellite and started the repeater back up around ~2030Z, and lowered the output power to about 300 milliwatts. Battery voltage was low, around 4.9v, with cell 1 less than 1 volt. This is very troublesome, as the impending third cell failure will likely end our continuing operations, particularly if it fails shorted as the others have.
We’ve also observed the transmitters cutting off around 4.7 to 4.6 volts prior to the last reset, in eclipse.
We’ll do what we can, but her days are short. Let me ask once again for more reports, especially from the US operators, to thehttp://oscar.dcarr.org/ webpage. The command stations monitor this for changes in the operation of AO-51, and while worldwide participation is good, few US operators post to it.
Please support the several satellite programs worldwide, such as AMSAT-Fox, AMSAT-UK FUNcube and UKCube, AMSAT-ZL Kiwisat, AMSAT-DL P3E, and others.
VI6CHOGM, celebrating the Commonwealth Heads of Government Meeting in Perth Oct 28-30, will be active on the amateur radio satellites SO-50 and AO-51.
Adam VK2YK writes:
Below are the passes this weekend that I’ll be active on with the special event callsign VI6CHOGM. All dates and times are in UTC.
Friday 28 OCT 11
SO-50 – 0530
SO-50 – 0710
AO-51 – 0714
AO-51 – 0852
Saturday 29 OCT 11
SO-50 – 0559
AO-51 – 0636
SO-50 – 0739
AO-51 – 0812
Sunday 30 OCT 11
SO-50 – 0627
AO-51 – 0733
SO-50 – 0808
AO-51 – 0912
Hope to hear you on the birds this weekend. Check out
http://vi6chogm.com/ for more info on freqs being used.
AMSAT Vice-President of Operations Drew Glasbrenner, KO4MA reported
the AO-51 Command Team is having a difficult time trying to restore
AO-51 to operation.
The current situation is the satellite will not retain the upload of
the flight software across eclipse. The batteries are in very poor