Mac lc.jpg

Powered by the Motorola 68020 CPU at 16MHz. Apple planned this "Low Cost" system to target education markets, and the Apple IIe Card helped phase out the use of Apple II systems in schools. The LC was available either with two floppy disk drives or a hard disk drive and floppy disk drive.

Replaced by the Macintosh LC II.

General Information

Released in October 1990, the Mac LC was named for its low cost. It was aimed at the home market, and included a 16 Mhz 68020 processor. It shipped inside a newly designed small case and was one of the first Macs to come bundled with a microphone. It also came with a new PDS slot, that became a standard in the LC family until its demise in early 1998. The LC was priced at $2,400, and was discontinued in December 1992.

Codenames: Pinball, Elsie, Prism. Originally shipped with system software 6.0.7.

CPU

16MHz Motorola 68020 processor, 16-bit internal data bus.

Memory

Maximum RAM capacity is 10MB.

Video

256KB VRAM, expandable to 512KB.

Expansion

Single "LC PDS" port for expansion needs. Common upgrades include the previously mentioned IIe card or an Ethernet card, which could also include a socket for a math co-processor as the LC did not include one (this will vary depending on card manufacturer).

ROM

ROM size is 512KB.

Notes

  • The Macintosh LC and Macintosh IIsi don't have restart and interrupt buttons like other Macs, so to generate these signals from the keyboard, press Command-Control-Power (the key with the triangle on it) for "reset" and just Command-Power for "interrupt."

Troubleshooting/Repair

Capacitor replacement (logic board)

The SMD capacitors on the logic board will most likely have already started leaking electrolyte out the bottom, and failing to replace them in a timely manner will result in further leakage with possible damage to nearby components. See below list of capacitors to replace:

  • 5 x 47uf 16V
  • 1 x 100uf 6.3V
  • 1 x 1uf 50V
  • 8 x 10uf 16V

Capacitor replacement (power supply unit)

A dead LC PSU can typically be revived by replacing all of the aluminum capacitors and cleaning up any leakage. Any working LC power supply should also be recapped as the capacitors will likely already be leaking due to component age, and the unit will eventually fail. See below for the parts list based on PSU vendor.

NOTE: these values may differ if there happens to be multiple revisions of a certain model.

TDK

  • 1 x 180uf 385v
  • 2 x 270uf 25v
  • 3 x 1000uf 10v
  • 1 x 8.2uf 50v
  • 1 x 56uf 25v
  • 1 x 47uf 25v
  • 1 x 270uf 10v

Dyna Comp

  • 1 x 180uf 400v
  • 1 x 2200uf 10v
  • 2 x 1000uf 10v
  • 1 x 330uf 35v
  • 1 x 33uf 35v
  • 1 x 10uf 35v
  • 3 x 82uf 35v

ASTEC

  • 1 x 180uf 400v
  • 1 x 47uf 35v
  • 3 x 1200uf 10v
  • 1 x 470uf 16v
  • 2 x 120uf 25v
  • 1 x 1200uf 16v

Diagrams/Schematics

 

Gallery

Documentation

See Also

External Resources