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Rescuing my dad's Classic II, last working in 1996


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When I went up to the attic a couple of years ago to help my dad out with something, I spotted an old Mac box. Curious, I asked if I could take it downstairs and test it out. "Sure, but that thing hasn't worked since before you were born," he said. Undeterred, I lugged the box downstairs and discovered:

  • A Macintosh Classic II
  • Its peripherals (mouse, keyboard)
  • Some extra no-name keyboard
  • All the documentation, manuals, etc that came with the machine
  • The receipt of purchase
  • An old Apple printer

Everything looked to have been kept in pretty good condition all those years, minus some yellowing of the Mac and its peripherals. Well, time to see just how "broken" the Mac was. I plugged everything in and flipped the switch... and it came on, to a gray background and a mouse cursor! I was surprised that twenty years of leaving it alone seemed to have actually fixed it, at least until I realized that there should probably be something else coming on the screen soon. Thinking it was just a matter of old hardware needing to "warm up", I left it on that screen for about thirty minutes, before turning it off and back on... only to see an image similar to this (I didn't think to take a photo of this back then, I guess):

 

Apple-Macintosh-Mac-Classic-II-NOT-WORKING-checkerboard.jpg.0ebedd7f662d7dd57e8ccbcfe7bf5114.jpg

 

Disappointed, and with zero experience with old Macs, I turned it off and put it away again, this time into my closet with the hope that someday I could gain enough experience to come back and fix it.

 

A year or two later, over Thanksgiving break, I was watching some YouTube videos about classic Mac restorations and I figured, why not give it a shot? By this point I was a little more comfortable fixing  electronics as I'd finally gotten over my fear of royally screwing something up while soldering and after all, how much worse could it get? I pulled it out again and just turned it on to make sure it was the same as I'd left it... but oh boy it had gotten worse (artist's rendition as I lost the photos and I can't find anything similar online):

 

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The CRT display was going nuts, just showing a crazy wobbly tornado instead of any perceivable image. I quickly shut the machine off, hoping to not cause any further damage, and started doing my research on what exactly this was. I ended up stumbling across this forum as well as the Classic Mac Repair Guide, which were both extremely helpful resources in what was to come. I learned what the most common causes of CRT issues were, and basic cautionary tips regarding working with a CRT, which I'd never done before. When I showed the issue to my dad, he told me that this was definitely unrepairable and that I shouldn't waste any effort on it.

 

...but of course, I knew I had to at least try.

 

Disassembling the machine, I found that the top two long screws were missing (presumably from an attempt my dad must have had at fixing it two decades prior) but hey, who needed those anyway? Once I was in I first took a look at the analog board, knowing that the problem the CRT had was definitely wasn't something the logic board could even do, regardless of how faulty it was; the CRT itself was literally being incorrectly driven. Once I removed the board from the case and took the little paper off that told me not to touch it, it was clear that something had seriously gone wrong:

 

IMG_20171123_141847_-_Copy.thumb.jpg.6a7b542196f7eed60cabcafb8412da9d.jpgIMG_20171123_161030_-_Copy.thumb.jpg.f5f8b5658e805e1bfbf29cde087dbcf5.jpg

 

That whole group of capacitors decided they wanted to fail and leak all over the damn board. I was very disappointed, as now it truly seemed impossible to fix. Even if I replaced the capacitors, there seemed to be no way that all of the traces were intact, and not really knowing what I was doing, I decided the best thing to do would be to ask on here to see if anyone had a spare they could trade/sell me. Unfortunately all I got were some answers with "recap the logic board first" which, while I'm sure were well-meaning, weren't exactly the most helpful. After all, how could I begin to diagnose a logic board issue without even being able to see the screen?

 

I decided to eschew the logic board repairs for the moment (I highly doubted a few extra days would make the capacitors on the logic board any worse than they had gotten over the last twenty years, and besides I needed it so I could at least be able to see something from the CRT). I wrote down the capacitors' specs and bought them piecemeal from DigiKey, making sure to grab the ones that were higher quality and rated for higher operating temperatures. At this point I had to go back to college for a few weeks, deigning to come back over the winter break and finish this once and for all.

 

A few weeks later, I was back home and roaring to go. I grabbed the capacitors from where my dad had held onto them and took the analog board out of the Mac. I still wasn't sure whether or not this fix would actually work, but I was already seven dollars in the hole; I couldn't back out now! I cleaned off the board as best I could with some isopropyl alcohol and got to work desoldering the capacitors and replacing them with their new counterparts. I was too engrossed in the task to actually take any photos during this process, but trust me when I say it looked a lot like the first photo above, just with capacitors that actually wanted to live. I put everything back together, plugged the Mac in, crossed my fingers the analog board wouldn't just explode, and flipped the switch...

 

Apple-Macintosh-Mac-Classic-II-NOT-WORKING-checkerboard.jpg.0ebedd7f662d7dd57e8ccbcfe7bf5114.jpg

 

...success! The CRT had come back to life (and yes of course I forgot to take a photo of this step, why do you ask). Now it was finally time to tackle the logic board.

 

IMG_20171224_000512_-_Copy.thumb.jpg.edd2bc5b91c896f9f57b45eacc214cfd.jpg

 

Yep, it was a little on the corroded side, but not that bad, all things considered. The battery hadn't exploded, thankfully, so all that was needed was a little TLC with the infamously-terrible electrolytic capacitors. I knew I would have to replace them soon but wanted to see if just cleaning the board a little, and maybe reseating some removable components, would bring it up to some semi-working state. I took a cotton swab and isopropyl alcohol to the board, scrubbing everywhere I could, hoping I could get some new behavior. I reseated the RAM, the ROM chips, everything I could. Then I put it all back together and came to the next moment of truth: would any of this actually do anything or would I just need to be patient and wait for the new caps?

 

hs_MacintoshPlusFloppy_011.thumb.jpg.66d9f58a82996ee28b19a1748e6488d1.jpg

 

...holy shit. It booted! It couldn't see the hard drive but it booted! I turned it off and (after some research) booted it from ROM successfully as well! There was no sound but wow, I couldn't believe it. I brought my dad in to see it and he couldn't believe it either. "I did not expect this machine to ever work again! That's incredible!" Unfortunately, without the hard drive working, none of his actual files were visible, but damn if he wasn't seriously impressed that I'd managed to get this far at all.

 

Little did he know, I wasn't done yet.

 

The next day was Christmas Day, and after all the presents from the tree were opened and festivities were had, I went back to the Mac. I'd been thinking since the previous night about the hard drive issue. Was it just a matter of the caps on the board preventing the hard drive being seen? Maybe, but whenever I turned on the machine without forcing a ROM boot, I could hear a strange sound, almost as if the hard drive was spinning up and attempting to be read, but the head wasn't moving, sort of a clicking sound. Doing some more research, I found out that apparently, the hard drives on these old machines were prone to doing this due to rubber bumpers inside the drive, meant to stop the head from going too far in either direction, had basically become gloopy, sticky messes and were most likely the culprits holding the drive head hostage. I'd never opened a hard drive before (at least, not without intending to introduce the platters to a hammer) so I was worried one wrong move could lose the files on there permanently. But hey, what was there to lose? It's not like they were accessible now.

 

I got the hard drive open, but at the cost of the tip of one of my dad's screwdriver bits (in my defense, the outside of the spindle seemed like another screw I needed to remove). Once inside, all I had to do was remove some screws on a little plate that goes over the drive head and magnets... and I ended up stripping one of the screws. Whoops. There was definitely no way of extracting that screw now; any attempts to drill it out would undoubtedly spew metal debris all over the platters. So I did the next best thing: I cut strips of electrical tape and used some tweezers to oh-so-carefully maneuver them under the plate and around the melted bumpers. This was an extremely time-consuming and nerve-wracking task, as a wrong move here could mean the scratching of a platter, and therefore the complete loss of data. Eventually, after about an hour or two, and with some help from my dad (who had come back to find me with the hard drive open, and was once again letting me know that I was probably wasting my time), I finally got the bumpers wrapped with electrical tape. Resealing the drive, putting it back in the machine, I also had little hope that it would ever work again. I'd almost definitely let too much dust get inside, or bumped the platters with one of my tools, or the electrical tape wouldn't do anything, or something else would just not work. I plugged everything back together, and for the third time, I prayed to the 68k gods that I hadn't just royally screwed the pooch. I switched it on, the screen slowly turned on, the hard drive spun up...

 

And this time, there was no clicking.

 

1604034879_IMG_20171227_230002-Copy.thumb.jpg.8efde8c13586c55056204cc633d2cc6d.jpg

 

"OH MY GOD I FIXED IT! DAD!" I yelled, pumping my fists into the air. My dad came running back into the room. "Really? No, I can't believe it! That fix actually worked?" he exclaimed, his incredulousness nearly matching my own. Once he saw the welcome message he'd set more than two decades prior on the screen, he started laughing. "Wow, I don't remember setting that, but it seems like something I would have written. I can't believe it. I never thought you would get the machine working at all, let alone the hard drive!" Once it got to the desktop he started poking around at all the files, digging up some old letters he'd written to my mom, and finding some games he remembered playing, like a shareware version of Tetris:

 

IMG_20171225_143325_-_Copy.thumb.jpg.61b1529addb8147449bb79fdc7cff739.jpg

 

It was an incredible feeling, seeing my dad playing a game on a machine that he and I used to think would never work again. Not to mention, this was probably my biggest repair ever, and to have had it end up so successful gave me a huge boost in confidence to try and fix more stuff I had lying around. I even managed to repair an old copy of Pokémon Yellow a friend gave to me in fourth grade that just stopped working (one of the traces inside had corroded). Over the next few days, I sourced some tantalum capacitors from a forum member here and recapped the logic board, finally bringing sound back to the system and ensuring no further damage would occur:

 

IMG_20180105_175351_-_Copy.thumb.jpg.0186f61ab007b515131df8a55ec576ab.jpg

 

I also got a new battery so the date and time could be kept (for no other reason than completeness), and adjusted the yoke on the CRT since the picture was slightly tilted.

 

IMG_20180105_221641_-_Copy.thumb.jpg.2bdd575cd43fc206616538ddfd1730df.jpg

 

Finally, I considered my work done, and I immediately went to post it here... a year later. Whoops. Of course, now I want to go back and clone the drive to something else, probably an SD card, but that'll have to wait until this summer when I'll have more time at home.

 

I hope you guys enjoyed my story, and sorry for the dearth of actual progress photos.

Edited by Diegoisawesome
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17 minutes ago, Paralel said:

Yep.

 

However, Alaska360 and I made an FPU/ROM expansion card for the Classic II, and you can burn updated System Rom's to allow for booting from the ROM expansion. But that's about it.

Ah, that's my bad then. Unfortunately it seems I can't go back and edit the post now, for whatever reason...

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