AO-92 turn off 14.09.20

  • Hi,


    i become this mail via Amsat-UK from


    Ciemon G0TRT



    I see this morning that Drew Glasbrenner K04MA has turned the AO-92


    transmitter off completely in order to come up with a plan to fix the sat's

    battery and software issues. I guess this will have a knock on effect onto

    the other FM sat's.



    There also seems to be a call for it to come back in "permanent" L/V mode

    which will no doubt raise a few eyebrows.

    73´s de Rico DO3ASE

  • Drew KO4MA wrote...


    Just to clarify, we can neither fix the batteries or software. The time is to come up with a plan to manage what little life is left. It is unlikely that any mode we choose to run lasts more than an orbit or two.

    73, Drew KO4MA


    I'm curious what will come out. Or did we lose him? 73s Rico

    • Official Post

    Subject: Re: [amsat-bb] AO-92

    It's been in Facebook and on Twitter. Maybe I said something here a few
    days ago. In any case, its battery is having trouble keeping it running
    through eclipses. It then goes into auto-safe mode. There is apparently a
    bug in the software that I wrote for the Foxes so that under some
    circumstances it "forgets" that it went into safe automatically and stays
    in safe mode even when the voltage comes back up after it enters the sun.
    In that case we have to wait for a command station to re-enable it. This
    is not too tenable over the long run, so I'm not sure what the ops people
    plan to do. It would be nice if the batteries failed open so it worked
    reliably in sun like AO-7. Unfortunately, that did NOT happen with AO-85.
    We'll see with 92.

    73, Burns WB1FJ
    AMSAT Flight Software

    Subject: Re: [amsat-bb] AO-92

    I've mostly been posting about it on Twitter.

    AO-92 has a cell that's failing, and towards the end of many eclipses it
    goes into auto-safe mode at 3.6v. If the battery drops low enough the IHU
    resets, and it comes back up in normal safe mode. Mark and I have been
    commanding to repeater mode on the first available pass after the resets,
    but it's not a long term sustainable answer. Last night Mark commanded the
    transmitter completely off while we consider a plan of action.

    Leaving autosafe on and the tx off, we may be able to turn the repeater on
    ad-hoc for weekends or such, completely dependent on command station
    availability. Turning autosafe and the IHU off like we did with AO-85 will
    kill the satellite pretty quickly, so that's not a good response either. So,
    we'll look at resets and battery states before this weekend and see where we
    stand.

    73, Drew KO4MA
    AMSAT VP Operations