The System

Ampro Little Board Plus Printed Circuit Board

Building Up the Ampro Little Board Computer

Add a power supply, disk drive, and serial terminal for a complete system. Box optional. It doesn't get much easier than that.

Ampro, the Easy DIY Computer

Before The Little Board

In 1980, Jim Fergguson and Digital Research Computers released the "Big Board", a single board computer designed to run CP/M. A unique feature was its form factor, it was designed to ride piggyback on the then-standard 8" floppy disk drive. This made for a compact system design, allowing the computer itself, its disk drives, and the terminal (driven by electronics included on the Big Board, another cost savings) to all be placed in a single enclosure.

In 1982 an improved version of the Big Board became available, with a faster processor and inclusion of many of the common add-ons to the Big Board in its design. It was still sized to ride on an 8" drive.

The price and convenience made both these systems very popular.

The Little Board

In 1984, Ampro released the "Little Board", a new single board computer based on the Z-80. It was designed to fit on a 5-1/4" "mini-floppy" disk drive. While the Big Board was sold in kit form as well as assembled and tested, the Little Board came assembled and tested only at a low price. It omitted the electronics that the Big Board had for interfacing directly with a CRT display and a keyboard, but by this time terminals had dropped in price relative to other system components (in 1980 a standard CRT terminal, even in kit form, often cost more than the rest of the computer system.)


SpecAmpro LB+Ampro LBBB IIBB
CPUZ-80, 4MHzZ-80, 4MHzZ-80, 4MHzZ-80, 2.5MHz
Disk4, 3.5 or 5.25"
4, 3.5 or 5.25"
4, 5.25 or 8"
4, 8"
CRT OutNoNoYesYes
Keybd InNoNoYesYes
Serial1x9.6kBd, 1x38.4kBd1x9.6kBd, 1x38.4kBd2x38.4kBd2x19.2kBd
Parallel1 full1 full2 full2 8-bit
NotesSame power and data connector as 5.25" floppySTD bus, EPROM programmer 
Power5V 0.95A, 9-12V 0.05A5V 0.75A, 12V 0.05A5V 3.5A, 12V 0.25A, -12V 0.2A5V 3A, 12V 0.25A, -12V 0.2A
Size (in.)5.75 x 7.75 x 0.755.75 x 7.75 x 0.758.875 x 14.5 x 0.758.5 x 13.75 x 0.75
Release Date1985198419821980
Ampro Little Board with Component Annotations
[Click to Enlarge]
Ampro Little Board Plus Circuit Board

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