benanderson89
Well-known member
The Macintosh Classic I've been working on is now done. All the large electrolytic caps on the analogue board and the caps on the logic board were all replaced. Voltages measure stable and within spec from the floppy disk port. C2 on the CRT neck board was also replaced.
However I've noticed that when the computer is left switched off for a long period of time, the voltage readings are very low, the screen is the wrong shape, it shakes violently and there's a chequerboard pattern. If you wait, the voltage eventually creeps up and it boots (but the memory check takes a while), wait even longer and the screen eventually returns to the correct shape and stops shaking.
Anyone know what could cause such an issue?
However I've noticed that when the computer is left switched off for a long period of time, the voltage readings are very low, the screen is the wrong shape, it shakes violently and there's a chequerboard pattern. If you wait, the voltage eventually creeps up and it boots (but the memory check takes a while), wait even longer and the screen eventually returns to the correct shape and stops shaking.
Anyone know what could cause such an issue?