ProDave
Well-Known Member
I have an old Authelm 800 tillerpilot. It's broken.
Last time I tried using it, a couple of years ago the arm just extended at full speed as soon as you applied power. (it had worked before that)
I have only just got around to trying to repair it.
Initial diagnosis, one of the transistors that forms the H bridge to drive the motor was dud. I have replaced the pair that make up that side of the bridge.
Now when you power up, the motor does not move, but the "sounder" is sounding continuously. Normally that just chirps when you push a button.
Anyone know what continuous sounding of the sounder means? but more importantly has anyone ever found any service information e.g. a circuit diagram would be good.
I did a sanity check with an oscilloscope and there is logic activity on most pins of the big processor chip but not having any service data I can't make any sensible tests.
Last time I tried using it, a couple of years ago the arm just extended at full speed as soon as you applied power. (it had worked before that)
I have only just got around to trying to repair it.
Initial diagnosis, one of the transistors that forms the H bridge to drive the motor was dud. I have replaced the pair that make up that side of the bridge.
Now when you power up, the motor does not move, but the "sounder" is sounding continuously. Normally that just chirps when you push a button.
Anyone know what continuous sounding of the sounder means? but more importantly has anyone ever found any service information e.g. a circuit diagram would be good.
I did a sanity check with an oscilloscope and there is logic activity on most pins of the big processor chip but not having any service data I can't make any sensible tests.
