I often feel like I've been unlucky enough to buy something on Yahoo Auctions. I thought this Mac Classic was a so-called checkered flag screen with a bad ROM, but it's actually a battery bombed Mac, and there are traces of removing this floppy disk drive, and the seller bothered to replace it with one that doesn't work. It seemed that he sold me a collection of garbage. Wow, amazing! I really appreciate it !!! I thought of throwing it out the window...
Amazing rust corrosion. Partially missing...lol
The analog board is fixed with rust and cannot be removed.
It is doubtful whether the RTC, VIA and sound chip are still alive...
The back layer remains barely clean.
I could have resold it on Yahoo Auctions as well, but I hate it... so I didn't. I've been sleeping in a warehouse for a while. Having built a Bolle's SE/30 Recreation a while back, I figured I could bring the logic board back to life with half the effort.
Macintosh Classic Reloaded is open sourced project, but I contacted Kai Robinson, who was in the same Discord community (We seem to have had a discussion of parts or something in the past but forgot), and got his approval to make this, and decided to build it!
Logic board production
Boards can be purchased from Mark Jozaitis' Mac Effects or built by uploading Gerber data to a PCB company. I made it at a PCB company.
The current Classic Reloaded version is 1.2, but the following points need attention:
- The drill data of Gerber data was delivered without holes for the DB25 and DB19 mount latches, which are SCSI and Floppy connectors. I made the holes because I was able to confirm that the inner layers were ground fills only. *MacEffects boards are neatly perforated.
- Since the hole for the reset switch leg is small, it is necessary to press it with pliers to make the leg a little thinner.
- Similarly, the hole in the RAM expansion slot was small, so the genuine connector could not be installed. Replace this with a double row pin header.
First, I transplanted the chip parts on the back layer. Of course, when transplanting, measure the resistance value of the resistor and the capacity of the capacitor and transplant it so that there is no mistake. This work alone took about 3 hours.
After that, the PLCC parts and other parts are soldered to complete the assembly. If you remove the top layer parts while cleaning the IC legs, it will take time. Especially this time, I had to wash the patina and black rusty legs carefully. For Classic, having to surface mount RAMs with tight spacing is a bit of a pain. Instead, there is no memory socket, so it's easy there.
For the top layer parts, it is easier to solder the PLCC and SOC parts first.
It was assembled cleanly, but this time it did not start at the first time. Woops, there was no screen display on this one!
After looking at the Bomarc schematics and tracing the video output lines, I realized that I had soldered the UE3 and UF3 ICs by mistake. That's the pink marker. After recovering the mistake, it started without problems. The analog board also didn't work at the same time so I tested it with another Classic II.
Analog Board Repair
The analog board was also broken lol, so of course I fixed it... I actually forgot to take a before pic. The analog board was stuck with rust and took time to remove.
The analog board had missing jumpers and resistors on the parts around the rust, but I was able to recover it. Most of the electrolytic capacitors have been replaced. Finally got it all working.
This area was terrible. it's beautiful now...
However, the cables were rusty and malfunctioning, so this time I replaced all the cables on the logic board.
The Worst Chassis Repair
I was at a loss as to how to repair the chassis. I bought this cheaply, so I figured I'd have to fix it without spending any money.
The chassis had a part where the iron was rotten and missing due to rust, but there was no iron plate that was just right, so I replaced it with brass.
Connection was done by solder brazing.
I also remade the logic board rail on the back, shaped it with putty and painted it. The paint is matte black.
Assemble
I used a floppy drive that I had repaired before. Of course, the eject gear has Tune-O-Gearinstalled.
The hard drive is of course BlueSCSI. Flash storage devices have a certain disadvantage of being silent. The Classic doesn't have an HD LED, so I used Beleth's Drum so that I could tell the access of the drive by sound.
All are only friends Geeks or my products. This is 2022, Amazing!
I created a all sponsor stickers and completed it.
Macintosh Classic / Stanic Mac Edition...
I showed this to my friend Mark Jozaitis and he said "That thing is absolutely beautiful!!! Makes me want to do a clear case for the Classic just for yours, ha!" lol
A little chat with Kai Robinson
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Kai Robinson , UK
Founder of Tinker Different, Engineer, vintage Mac expert
Creator of the Mac SE Reloaded, Mac Classic Reloaded etc
What inspired you to do this reverse engineering?
Kai: Well, I started because I got involved in the commodore amiga community project to re-engineer the amiga 500+, which was almost certainly battery bombed by now. John "chuckygang" Hertell from Sweden had developed the process with the Amiga 1200, so a group of us thought it would be just as easy to do with an A500+, even easier because its just a 2 layer board.
What kind of difficulties did you face in the SE Reloaded project? Were there any difficulties that were different from the Amiga?
Kai: Difficulties, yes, the initial realisation that the pcb is a 4 layer board, not just a simple double sided pcb, was something new. However it was easier when I realised that the inner layers were merely power planes. Either GND or vcc
Also, the split power planes on the rear i/o, had to learn a totally new skill in the SPRINT layout software!
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Thank you from bottom of my heart, Kai! If you didn't make this board, my Mac Classic would be garbage. This is true! More board designs like this will allow recovery from battery bombs. May happiness come to you!
And thanks to my friends:
Stephen Arsenault (BetterBit, Satanic Mac Club)
Drake (BlueSCSI CA, Satanic Mac Club)
Alan Williams (Williams Works, Kero's Mac Mods, Infinity Products)
Eric Helgeson (BlueSCSI)
James Wages (YouTuber)
okkun (MusiMagic)
Mark Jozaitis (MacEffects, Tune-O-Gear distributors)
Bill Martens (Call-A.P.P.L.E. Magazine)
When next summer comes, I plan to RetrObright it!
Until the end Thank you for reading. Have a nice hack!