I have an M1297 to match my Macintosh II, and other than a slight bit of distortion at the top I've not really had problems with it. But recently, whenever I power it on, the monitor will come on for a second and then shut off. I hear the degauss sound, and the LED on the front comes off, but then go off. No picture on the CRT of course.
So I assume it's some problem with the power supply. The way it acts is like some sort of overcurrent protection. The past few times it did this, I would take it apart, unplug some wires, discharge the anode (it never is actually charged, because the CRT would only be on half a second), and when I would power it back on it'd magically work again. But now it doesn't. I made sure to take out the power supply. The fuses haven't been blown, none of the caps are leaking or bulging in any way. The board wasn't cracked, and I didn't see any solder joints that looked bad. I cleaned the board off. Nothing has fixed the problem, so at this point I'll probably try to recap the power supply, and while I'm at it I probably will recap the other boards as well (since there is a bit of distortion at the top)
But given that the caps look fine, I'm not sure that they are actually the issue causing this.
So I assume it's some problem with the power supply. The way it acts is like some sort of overcurrent protection. The past few times it did this, I would take it apart, unplug some wires, discharge the anode (it never is actually charged, because the CRT would only be on half a second), and when I would power it back on it'd magically work again. But now it doesn't. I made sure to take out the power supply. The fuses haven't been blown, none of the caps are leaking or bulging in any way. The board wasn't cracked, and I didn't see any solder joints that looked bad. I cleaned the board off. Nothing has fixed the problem, so at this point I'll probably try to recap the power supply, and while I'm at it I probably will recap the other boards as well (since there is a bit of distortion at the top)
But given that the caps look fine, I'm not sure that they are actually the issue causing this.
