Apple LCIII Restoration

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This page documents the the restoration of an Apple Macintosh LCIII bought from ebay for $10. This LCIII will be the replacement for my Pop's LCIII, which was forever lost in Brisbane's 2011 floods.


  • Run a HTTP server, and serve static pages on the Internet.
  • Relive some great times playing Maelstrom.
  • Develop a custom SCSI-2 to SD Card converter (see SCSI2SD), use the converter to boot the LCIII, and win a bet. I shall enjoy eating free Nandos. Cheers AJ.

As-bought Condition

Part As-bought State Current State Comment
Keyboard Missing Still missing
Mouse Missing Still missing Replace with Apple_Desktop_Bus_Mouse_II ("Teardrop" mouse).

Macintosh Portrait Display
15" 640 x 870 8-bit greyscale.
Manufactured June 1992.

Heavy yellow discolouring. Unknown working state. Replaced with a standard VGA monitor. See Macintosh VGA Uses a somewhat non-standard 13w3 connector. This was not the standard (colour) monitor that was supplied with the LCIII, and I probably won't bother trying to get it going. An adapter cable to make use of a VGA monitor is more than sufficient.
Power supply

Dyna Comp Inc DCF 353.
Apple part no. 614-0028
+5v: 4.75A
+12V: 1.0A
-5V: 0.075A

All rails read 0V on the multimeter.
(Temporarily) replaced with an older ATX power supply that still had the -5v rail. Old, yet still-working, LC power supplies are fairly easy to find on ebay and elsewhere. However, these old supplies won't last forever. I plan to replace this with a small circuit board that accepts an ATX power supply input, and creates the required -5v rail. This then allows me to use an easy-to-find PicoPSU (or similar), and replace the supply in the future if it fails.
SCSI Hard drive

Apple branded Quantum Pro Drive 500Mb LPS270 (Firmware copyright Apple Computer Inc. 1994)

The drive controller appeared to work when connected to a modern PC with PCI SCSI card, but the drive refuses to spin. No amount of hitting, freezing or swearing could convince the drive to spin.
Working SCSI device required to boot Drive will be replaced with a custom SCSI -> SD card device. SCSI2SD

Feb 1993
Serial *SG3077K4VA3*

Significant discolouration. Requires restoration to remove the discolouration A Hydrogen peroxide solution + UV light can be used to restore the case to its former glory. Just take care to mask the Apple logo at the front. See [1]
Logic board

Apple part no. 820-0650-A
CPU Socket: MC68882FN25A (FPU)
CPU (Soldered to board): MC68030FE25B

Confirmed working. Working On boot, the distinctive power-on sound is heard, followed by a flashing question mark in a disk icon (since no disks are working yet).
Ethernet expansion card (10Base-T, RJ45)

Apple Computer Inc 1993 Ethernet LC Twisted-Pair card
Apple part no. 630-0891-B

Unknown Not required Could make use of the RS-422 serial port to run a PPP connection if the ethernet card doesn't work.
Floppy drive Unknown Not required This drive is probably not required anymore. Trying to find working floppies is difficult, and they will only degrade further over time.
VRAM Upgrade

Apple part no. 820-0605-A

Unknown Not required This is a 512KB upgrade, but the LCIII only supports a total of 768KB, including the 512KB on-board VRAM.
RAM Upgrade

Samsung KMM5321000CV-7 9428 4MB 72pin 70ns

Unknown Unknown Could be replaced with a 32MB SIMM. An additional 4MB onboard memory is available on the logic board, but this is probably insufficient to do anything useful.


new_LCIII_first_contact_20110927.jpg Hacked up VGA cable and ATX power supply attached. No boot disks.