Originally Posted by
luge_racer
Yes Dirk, I understand that I could disconnect the GSU. For my own reasons I chose to mount it in the aircraft.
However, that's not the issue at hand. The issue is the tach anomaly. The GSU is the only tool I have to read the turbine stats; so I have to rely upon what it says. Are you saying that the GSU is solely at fault and not the ECU or turbine sensor?
I would not say that the GSU is the faulty problem, nor the ECU or RPM board at this time. We have encountered this before, and have found the customer was using a switch with poor continuity that caused severe voltage drop to the to the system. Maybe your power box is not performing to spec under a load? I read what you wrote above, the question I will ask is, did you put a Volt meter to the throttle lead at the ECU, and get a static voltage reading, and then move the elevators,control surfaces and take another reading? The GSU requires a steady voltage to power the unit. If the power drops, the GSU processor will not function properly and will display what you are seeing. If you are getting the same voltage readings statically and under a load, I would suggest sending it back to us to be checked out. If you are getting big voltage drops, I would suggest finding the power drain in your system.
Dirk