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Apple Macintosh compact (128K → SE/30)

The "toaster" Macs (1984-1991): 68000/030, an integrated 9″ B&W screen, a major collector's item. Few games versus the games-focused micros, but strong restoration demand. A high-risk repair: internal CRT + analog board, a leaking PRAM battery.

Macintosh Plus

Macintosh Plus — photo by Maksym Kozlenko, CC BY-SA 4.0 (Wikimedia Commons).

Identification

Model Year CPU Note
128K / 512K 1984 68000 @ 8 MHz the founders, soldered RAM
Plus 1986 68000 SCSI, expandable SIMM RAM
SE / SE/30 1987-89 68000 / 68030 SE/30 = the most powerful compact, highly prized
Classic / Classic II 1990-91 68000/030 budget end of the line

Repair (technician)

CRT + analog board = high voltage

The compact Mac is an all-in-one: the CRT, EHT and analog board (PSU + deflection + video) are inside. Discharge the EHT and follow CRT safety before any work.

Leaking PRAM battery (½ AA 3.6 V)

The soldered/holder PRAM battery leaks and eats the logic board (especially the SE/30). Remove it right away, clean/neutralize, repair traces → backup batteries.

  • Recap the analog board: dried caps → screen folded to a line, "singing flyback", won't power on → Recap (community-documented analog kits).
  • Recap the logic board (SE/30, Classic II): leaking SMD caps → dead sound, checkerboard, "simasimac" → a full recap + cleaning fixes most "dead Macs".
  • Floppy drive (400/800K/SWIM 1.44 MB): mechanism / lubrication → service; emulators (Floppy Emu) common.
  • Flyback: whine / unstable image → tired component (rare, hard to replace).

Step-by-step disassembly procedures ✅

1 procedure transcribed from the iFixit guides, with difficulty and estimated time.

Procedure Difficulty Time
Macintosh Classic disassembly Moderate 30 minutes
Macintosh Classic disassembly

The Macintosh Classic is a computer mounted in...

  1. Turn the Mac so the screen is face-down Put a cloth under the screen to not scratch the screen. Unscrew the four Torx screws. Two screws are on the bottom side near the ports, the other two are Hidden in the handle.
  2. ++WARNING++, IF YOU COME INTO CONTACT WITH THE DISCHARGE FROM THE CRT YOU RISK DYING, We recommend looking for a on YouTube|new_window=true Connect a flat screwdriver to the CRT ground cable (black cable attached to the screw) with an alligator cable. Slowly push the screwdriver under the red suction cup connected to the CRT and touch the metal part with the screwdriver.
  3. The motherboard has no screws, so it can be removed by pulling upwards. Make sure to disconnect all cables.
  4. Remove the four screws and pay attention to the two hidden screws. The Floppy lock and Disk go away easily.
  5. WARNING - The POWER SUPPLY may still contain current inside it. Do not touch any capacitors on the power supply Unscrew the two screws that secure it to the chassis and remove the connected cables.
  6. To remove the Chassis you must use the same Torx 15 screwdriver as the handle. Unscrew the four screws and the Chassis can be removed.
  7. CAUTION: The cathode ray tube is under pressure, avoid scratching or breaking it. To remove the CRT, simply unscrew the four screws placed at the corners.

Source, licence and scope

iFixit guides (category "Macintosh Classic"), under Creative Commons BY-NC-SA — attribution, non-commercial, share-alike. Only the text is reproduced; step photos stay on iFixit. ⚠️ These guides target the model named in the title: on another revision, the screws and the disassembly order may differ.

Common faults

Symptom Likely cause Lead
Corrosion / dead sound / "simasimac" SMD logic-board caps (SE/30) Recap + clean
Screen folded to a line / no power analog-board caps Analog recap
Corrosion near the battery leaking PRAM Remove, neutralize, repair
Floppy not read mechanism / SWIM Service / Floppy Emu

Modernisation & mods

Modernisation & mods — what to buy, how

Leaking PRAM battery + CRT high voltage

Remove the PRAM battery without delay (it leaks and eats the board — SE/30 in particular) → clean/neutralize, repair traces. The recap targets the logic board (SE/30, Classic II) and the analog board (community kits). ⚠️ The compact Mac has a CRT: lingering high voltage (flyback) → discharge the tube before opening → CRT safety.

Modern storage - Floppy Emu (BMOW) 🟢: emulates the 400/800 KB and 1.44 MB drives and the HD20 hard disk from an SD card (external box) → direct boot, no more tired floppies. The flagship compact-Mac mod. - BlueSCSI / SCSI2SD 🟢 (Plus, SE, SE/30…): an SD card as a SCSI hard disk; PiSCSI/RaSCSI (Raspberry Pi) 🟡 adds disks, networking, virtual CDs. - ROM-inator 🟡 (SE/Plus): a replacement ROM (socketed) with RAM-disk/HD20 boot.

Video / display - Integrated 9″ B&W screen: no "color mod". On the SE/30 (030 PDS slot) you can add a video/Ethernet card for an external monitor and networking.

Reliability: recap 🟠 (logic + analog board); battery removal 🟡.

  • 030/040 accelerators and RAM upgrades 🟠 for slotted models.

⚠️ Do not host ROMs/System — method only.

See also

Sources & attribution

Review & corrections

How this space is used

Spotted a wrong value, an outdated procedure, a chip reference that does not match your board? Say so here, with what you observed (model, board revision, serial number, measurement). Every report is cross-checked against a source before anything changes — an unverifiable correction is published as “reported by …, not cross-checked” rather than silently applied.

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