Built by Mike Walters, 2008

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I built The Cy-borg for my good friend Cy Rawls after he was diagnosed with brain cancer. He passed away not long after he got the Cy-Borg in the mail. Cy wrote me an email after it arrived to say he liked it and how it would drive his parents' cat crazy!

The sound circuit for the Cy-borg comes from a toy cell phone. The # key is shorted to always stay on, and its clock resistor is routed two ways in parallel. First to thumbtacks on top, second to an optocoupler inside the case. This means the over all pitch and speed of the cell phone sound change by pressing the thumbtacks, and also when the LED side of the optocoupler gets charged. This LED inside the case is wired parallel to the LEDs that form the smile. When you press the red nose, all of the LEDs charge through a 47uF capacitor, that slowly fades the LEDs on and off. This causes the speed of the cell phone circuit to climb, and then slowly slow down. The photo resistor side of the optocoupler has some of its own hysteresis, so the action sounds a little like spinning a large wheel.

There's a speaker inside, an output, and a power switch.

cyborg side