Macintosh Classic

For more information, see this article's corresponding Wikipedia page: https://en.wikipedia.org/wiki/Macintosh_Classic.

Macintosh Classic

Preliminary Information
Release Year	1990
Leak Risk	Medium-High
Batteries	Lithium 3,5v
Mounting Technology	Through Hole, SMD, BGA, Sockets
Capacitor Types	Aluminum Electrolytic
Destructive Entry	No
Hardware Specifications
CPU	MC68000
Memory Capacity	1-2MB
Storage	3,5in Floppy Drive, 40MB HDD IDE
Display Interface	Proprietary

The Macintoshes Classic marked the decline and eventual end of the compact Macs. It was sold from 1990 to 1992 as the low end of the Mac lineup. It ran on an 8 MHz Motorola 68000 processor, which was remarkably slower than its contemporaries, but kept its appeal as the first Mac less than $1000.

Known Issues

Leaky Battery

Cause

• Age: Old batteries tend to go bad. The ones in the Mac Classic like to also leak and corode the motherboard, sometimes beyond repair.

Solutions

• First remove the battery (or what's left of it). Then try to neutralise the acid with something like soda. Clean the Board as good as you can. You might be lucky and get away with minor repairs like replacing a few components. There's a big possibility though that traces are damaged. In that case try to rewire them as good as you can with some external thin wires.

Leaky Capacitors

Cause

• Also age: Capacitors go bad just like batteries. Eventually they will leak all over your board.

Solution

• Try to clean the board as good as you can from the electrolyte. Then remove the capacitors one by one and clean again (A toothbrush and some isopropyl alkohol are pretty useful. For me, water and soap work better but hard water can leave behind awful stains which may also be conductive). Replace the damaged components that may be around and capacitors. All you have to do now is test it.

Disassembly Notes

Warnings or tips to disassemble the device

Replacement Parts

Analog Board

Observed from 820-0395-C / 630-0420 240v (European version)

Electrolytic Capacitors 820-0395-C / 630-0420 240v

RefDes	Qty	Capacitance	Voltage	Diameter/size	Height	Lead Spacing	Board Zone	Note
CP1, CP13	1	220 µF	400 V	22 mm	45 mm	10 mm	High Voltage	no need to replace
CP2	1	1000 µF	35 V	12,5 mm	31,5 mm	5 mm	Power Supply
CP4, CF1	2	47 µF	25 V	5 mm	11 mm	2mm (board has 5mm)	Power Supply
CP5, CP34, CP37, CL3, CP35	5	1 µF	50 V	5 mm	11 mm	2mm (board has 5mm)	Power Supply
CP6, CP36	2	2200 µF	10 V	12,5 mm	25 mm	5 mm	Power Supply
CP8	1	2200 µF	16 V	12,5 mm	31,5 mm	5 mm	Power Supply
CP12	1	1000 µF	16 V	10 mm	31,5 mm	5 mm	Power Supply
CP7	1	1000 µF	10 V	10 mm	20 mm	5 mm	Power Supply
CP9, CP10, CF4	3	470 µF	25 V	10 mm	15 mm	5 mm	Power Supply
CP11	1	220 µF	25 V	10 mm	25 mm	5 mm	THT Flyback
CP3	1	10 µF	25 V	5 mm	11 mm	2mm (board has 5mm)	THT Flyback
CL1	1	10 µF	50 V	5 mm	11 mm	2mm (board has 5mm)	THT Flyback
CL2	1	4,7 µF	250 V	10 mm	11 mm	5mm	THT Flyback
CF2	1	220 µF	16 V	8 mm	11 mm	5mm	Video Circuit
CF3	1	1000 µF	16 V	10 mm	20 mm	5mm	Video Circuit
CP31	1	1000 µF	6,3 V	10 mm	11 mm	5mm	Video Circuit

• 
  Apple Macintosh Classic Analog Board 630-0525 Rev B 120V
• 
  Apple Macintosh Classic Analog Board 820-0395-C / 630-0420 240v

Logic Board

Note model numbers and board revisions here

Capacitor Specifications and Footprint Information

RefDes	Qty	Capacitance	Voltage	Mount	Diameter/Size	Height	Temp	Type	Brand	Compatible Part Number	Order Links
C1, C2, C4, C5, C6, C8, C9	7	47 µF	16 V	SMD	6,4 mm	4,65mm	0 °C	Polymer Capacitors	J2	875105344006 / HV1V476M0605PZ	Digikey Mouser LCSC
C3	1	1 µF	50 V	SMD	4,2 mm

If parts are not available or different selection is preferred, you can use the values to perform a parametric search.

Kits

• Digikey BOM: https://www.digikey.com/

Related Links

• alxlab Mac Classic Analog Board 630-0395 / 820-0395-C (120V) capacitors list
• Theo Bouzige Mac Classic Recap Analog Board European V1