No no, it is not the title of a movie, today I turned on the Macintosh SE 1/20 and the Macintosh LC II and neither of them worked
The day before yesterday it was the the PC power supply (it is already replaced and working), the dishwasher machine (damaged motor) and today to the two Macs. I have come to think of a voltage surge but it is almost impossible, in the area where I live never happened but so much concentration of electronic breakdowns in four days it's annoying or maybe simple bad luck....
Anyway, the Macintosh SE 1/20 is already repaired, it was a false contact in two SIM modules, one that has two broken retention tabs broken and I fixed them in the past with hot glue and the other SIM module that has the contacts quite damaged. Contact cleaner, double zero sandpaper, eraser rubber and alcohol and I have only managed to leave them as the photo shows so I don't know how long it will work. At least for now it works.
What really worries me is the Macintosh LC II. When turned on, nothing appears on the screen, there's no "chord" sound and although the hard drive tries to boot there it stays. It is also not possible to boot from floppy because the drive does not load during boot. The fan of the box does turn, is the only part that works.
I have measured the power supply output voltages and all of them are correct. I have removed the network card, disconnected the hard disk, the disk drive and even the memory SIMs and the problem remains, It only turns the fan but does not start, so I think that most probablt the malfunciton is located at the motherboard. Visually there are not damaged components and leaving the Mac turned on for 5 minutes, only the microprocessor is a little warm, but not more than normal.
The Apple service manual arrived at this point proposes to replace the motherboard, but now it is not easy to find one of these in conditions in Europe...
Can I do some more test to try to find out what is wrong or is better to forget it and start to look for a second-hand motherboard?
The day before yesterday it was the the PC power supply (it is already replaced and working), the dishwasher machine (damaged motor) and today to the two Macs. I have come to think of a voltage surge but it is almost impossible, in the area where I live never happened but so much concentration of electronic breakdowns in four days it's annoying or maybe simple bad luck....
Anyway, the Macintosh SE 1/20 is already repaired, it was a false contact in two SIM modules, one that has two broken retention tabs broken and I fixed them in the past with hot glue and the other SIM module that has the contacts quite damaged. Contact cleaner, double zero sandpaper, eraser rubber and alcohol and I have only managed to leave them as the photo shows so I don't know how long it will work. At least for now it works.
What really worries me is the Macintosh LC II. When turned on, nothing appears on the screen, there's no "chord" sound and although the hard drive tries to boot there it stays. It is also not possible to boot from floppy because the drive does not load during boot. The fan of the box does turn, is the only part that works.
I have measured the power supply output voltages and all of them are correct. I have removed the network card, disconnected the hard disk, the disk drive and even the memory SIMs and the problem remains, It only turns the fan but does not start, so I think that most probablt the malfunciton is located at the motherboard. Visually there are not damaged components and leaving the Mac turned on for 5 minutes, only the microprocessor is a little warm, but not more than normal.
The Apple service manual arrived at this point proposes to replace the motherboard, but now it is not easy to find one of these in conditions in Europe...
Can I do some more test to try to find out what is wrong or is better to forget it and start to look for a second-hand motherboard?