[SOLVED]Motor transistors keep dying on me
- Thread starter EmilFrid
- Start date
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@RoadrunnerOZ yes, those are always active.
Swapped the dual cap plus diodes – no difference, supply transistor died this time. It seems to select its victim randomly
Swapped the dual cap plus diodes – no difference, supply transistor died this time. It seems to select its victim randomly
So that leaves the other two run caps 102 and 104 or it’s the motor controller
Transistors Q1/2/3/4 or the IC’s could be faulty
@RoadrunnerOZ I've checked them and they measure fine. All logic behaves like it did when the machine worked
I am not sure if the actual voltage levels are correct, but those proportions seem logical to me as they relate to the torques being applied to the motors for the various modes.
Does the calibration manual provide any info about these levels?
Have you checked that the emitters are grounded back to 0V in the controller
That leaves the other two run caps and the motors themselves
And with the transistors removed what do you measure from the collector connection on the transistor socket to the emitter connection on the transistor sockets in the various modes? (I assume these will be independent of the modes)
It's weird as hell, I measure a bit past 400 DC at idle, and when I press rewind it goes down 10 volts or so, and when I press fast forward it jumps up around 10 volts (from idle, measured att supply motor collector-emitter). These values are perplexing to say the least
