Sunday, December 4, 2011

The End of AO51's 7 Year Journey

December 2011

From Drew, KO4MA, AMSAT-NA VP Operations:

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

AO51 was a great bird, and will be missed.  My first QSO via satellite was via AO51 on November 27, 2009, with K8TL.  My first 28 QSOs via satellite are shown below, all of which were via AO51.

AMSAT-NA is now kicking Fox-1 into high gear, and they are requesting your support.  See AMSAT-NA's website to donate, or you can use the PayPal widget on the right of this screen.


  1. Likewise Zack, I made my first satellite QSO on AO-51...with you! In fact it was nearly a year ago, on 12/20/2010. AO-51 will surely be missed but the smart guys at AMSAT extended its life so that I could get many of my VUCC contacts through it during the last eleven months, for which I and others are surely grateful.

  2. I would be interested to know how many people had their first QSO on AO51 as opposed to AO27, SO50, HO68, etc. I would imagine that the results would definitely favor AO51.