TC Jacobson & Associates LLC

Internet Development, Streaming Media, DVB Satellite

Computer Terminal for the Blind

In late 1976 I built a computer terminal for a blind friend , Kevin Fjelsted. As a computer programmer he had been using a modified ASR33 TTY that hammered out braille, and a device called an Opticon. The Opticon used vibrating piezoelectric elements to form the shapes of letters read by an optical wand on the operators index finger. The Opticon had a data interface… so I used one of our J&J 8080 single board computers, built an interface to the Opticons strange non TTL signal levels, connected a surplus shaft encoder from the inertial navigation system of an FB111 fighter jet, threw in some son alert beepers, and put it all in a suitcase. My roommate and friend Dan LaLiberte wrote some very nice 8080 assembly code, and soon Kevin was able to zoom around a virtual CRT screen with great fidelity.

Later, Kevin moved to Lawrence Berkeley Labs, and an acquaintance of mine there, Bob Fink, had it repackaged into a fancy case. There were numerous articles published about it, and I think several duplicates made for others. Now days I think blind programmers use voice output. Perhaps next time we will have to hook it directly up to his brain! 🙂

You can see the J&J 8080 board underneath the keyboard in this picture, a bunch of 2N222 transistors and some 74LS latches for the Opticon interface on a daughter board sitting over the power supply, and the FB111 shaft encoder (light blue, round) just above the numeric keypad. The Opticon is on the left, in a leather case.