Last ran around 2015. Was stored since and finally opened last week. I spent a good amount of time thoroughly washing, scrubbing and drying the board with alcohol to remove any and all traces of the electrolytes that were covering such a large portion of it.
I put the kemet tantalum capacitors in place of the old ones. One pad was lifted (by me) but the others all took solder and toned out when checking with my meter. I bodged the lifted pad and it seems to tone out.
I toned all of the IC legs that seemed to have a bit of corrosion on them and they at least appear to be making contact but I understand these legs can rot under the case. I also tried my best to ensure that none of the legs have a short to their neighbors.
Plugged it in and started it up. *Gong* then a gray screen with a cursor and floppy icon. The icon will swap to and from a question mark every 20-seconds or so. It's definitely not as fast as I expected. The animation just moves very very slowly.
To be clear, it chimes during every single startup no matter what configuration I try.
It never goes beyond this nor does any logic appear to be going on. The HDD spins up, chatters for a second, then remains spinning with zero "access" noise. Holding D, C, or any key combination doesn't force to boot from HDD or CD. I don't have a bootable CD but considering I can't seem to effect anything I don't know that it's worth bothering with.
I've also tried my BlueSCSI but I have no way of knowing whether that works or is even configured properly since I put it together today. There appears to be a red and blue LED on the BlueSCSI. The blue will flash for just a moment after the power button is turned on but only the red stays on after that. If this is an "access" light, I would expect it to begin flashing when I use the key command to boot to that device. Command+Option+Shift+Delete+6 doesn't do it even though the BlueSCSI is set to ID 6 in the boot image I put on there.
Here's the kicker. The Interrupt and Reset buttons on the back do nothing!
I'm having quite the day and just hoping somebody has a clue here. I have never really gotten into working on these classic Mac's so I'm hoping it's something obvious (to others).
Also, if I don't have power going to the CD-ROM or HDD, yet the SCSI cables are plugged in, does that properly terminate the internal SCSI bus?
Should I start checking power supply voltages? Only reason I haven't done so is that I read that it has to be measured under load.
------------Addendum------------
Just for now I checked the PSU voltages. Reds are all just over 5V. Blacks are all direct to ground negatives. Yellow and Blue...well one of them is just less than -12v (so about -12.08) the other is just less than 12v at about 11.91v.
What sync mode is safest for troubleshooting? I have a DB15 to HD15 adapter with dip-switches plugged into a VGA ViewSonic CRT. It's currently displaying when I set the jumpers for 480-resolution RGB modes but they all seem a little "off".
I have two sticks of RAM and have tried every combination in either slot including no RAM.
I have a new PRAM battery and have tried every process with and without it installed.
I tried changing the BlueSCSI to device 5 but the access light doesn't do anything beyond flashing once or twice at the moment the power button is switched on.
I have an aftermarket ADB keyboard and no key combination causes any difference in behavior. The Caps Lock light does appear when I press the power button so at the least the keyboard is getting power.
I put the kemet tantalum capacitors in place of the old ones. One pad was lifted (by me) but the others all took solder and toned out when checking with my meter. I bodged the lifted pad and it seems to tone out.
I toned all of the IC legs that seemed to have a bit of corrosion on them and they at least appear to be making contact but I understand these legs can rot under the case. I also tried my best to ensure that none of the legs have a short to their neighbors.
Plugged it in and started it up. *Gong* then a gray screen with a cursor and floppy icon. The icon will swap to and from a question mark every 20-seconds or so. It's definitely not as fast as I expected. The animation just moves very very slowly.
To be clear, it chimes during every single startup no matter what configuration I try.
It never goes beyond this nor does any logic appear to be going on. The HDD spins up, chatters for a second, then remains spinning with zero "access" noise. Holding D, C, or any key combination doesn't force to boot from HDD or CD. I don't have a bootable CD but considering I can't seem to effect anything I don't know that it's worth bothering with.
I've also tried my BlueSCSI but I have no way of knowing whether that works or is even configured properly since I put it together today. There appears to be a red and blue LED on the BlueSCSI. The blue will flash for just a moment after the power button is turned on but only the red stays on after that. If this is an "access" light, I would expect it to begin flashing when I use the key command to boot to that device. Command+Option+Shift+Delete+6 doesn't do it even though the BlueSCSI is set to ID 6 in the boot image I put on there.
Here's the kicker. The Interrupt and Reset buttons on the back do nothing!
I'm having quite the day and just hoping somebody has a clue here. I have never really gotten into working on these classic Mac's so I'm hoping it's something obvious (to others).
Also, if I don't have power going to the CD-ROM or HDD, yet the SCSI cables are plugged in, does that properly terminate the internal SCSI bus?
Should I start checking power supply voltages? Only reason I haven't done so is that I read that it has to be measured under load.
------------Addendum------------
Just for now I checked the PSU voltages. Reds are all just over 5V. Blacks are all direct to ground negatives. Yellow and Blue...well one of them is just less than -12v (so about -12.08) the other is just less than 12v at about 11.91v.
What sync mode is safest for troubleshooting? I have a DB15 to HD15 adapter with dip-switches plugged into a VGA ViewSonic CRT. It's currently displaying when I set the jumpers for 480-resolution RGB modes but they all seem a little "off".
I have two sticks of RAM and have tried every combination in either slot including no RAM.
I have a new PRAM battery and have tried every process with and without it installed.
I tried changing the BlueSCSI to device 5 but the access light doesn't do anything beyond flashing once or twice at the moment the power button is switched on.
I have an aftermarket ADB keyboard and no key combination causes any difference in behavior. The Caps Lock light does appear when I press the power button so at the least the keyboard is getting power.
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