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.)
Specifications
Spec | Ampro LB+ | Ampro LB | BB II | BB |
---|---|---|---|---|
CPU | Z-80, 4MHz | Z-80, 4MHz | Z-80, 4MHz | Z-80, 2.5MHz |
RAM | 64KB DRAM | |||
ROM | 4-16KB | 4KB | 2-12KB | 2-8KB |
Disk | 4, 3.5 or 5.25" DSDD | 4, 3.5 or 5.25" DSDD | 4, 5.25 or 8" SSDD | 4, 8" SSSD |
HDD I/F | SCSI-1 SE | No | SASI | No |
CRT Out | No | No | Yes | Yes |
Keybd In | No | No | Yes | Yes |
Serial | 1x9.6kBd, 1x38.4kBd | 1x9.6kBd, 1x38.4kBd | 2x38.4kBd | 2x19.2kBd |
Parallel | 1 full | 1 full | 2 full | 2 8-bit |
Notes | Same power and data connector as 5.25" floppy | STD bus, EPROM programmer | ||
Power | 5V 0.95A, 9-12V 0.05A | 5V 0.75A, 12V 0.05A | 5V 3.5A, 12V 0.25A, -12V 0.2A | 5V 3A, 12V 0.25A, -12V 0.2A |
Size (in.) | 5.75 x 7.75 x 0.75 | 5.75 x 7.75 x 0.75 | 8.875 x 14.5 x 0.75 | 8.5 x 13.75 x 0.75 |
Release Date | 1985 | 1984 | 1982 | 1980 |

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Ampro Little Board Plus Circuit Board