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SPO256-AL2 Speech Synthesiser board

This board uses the GI SPO256-AL2 speech chip from General Instruments, now Arizona Microchip Technologies. Similar circuits with the same chip, had been published in Elektor and Maplin magazines some time ago. The schematic included in the .zip are from No. 36 February 1990 Maplin Magazine. The control data are sent thru the PC parallel port to generate the allophones that form the words. There is included a small TBA820 audio amplifier with adjustable volume to drive a 0.5W loudspeaker. Single side PCB.

I got a SPO256-AL2 chip from THE BRITISH AMATEUR ELECTRONICS CLUB and they still have some Maplin kits available and many other cheap parts. Also BG Micro had they for less than $5.

Silk layout

SPO256-AL2 datasheets in PDF format and diagram from the Chris projects page.