Baby’s First 8 is a analog synthesizer/sequencer realized in discreet components (no MCU, no software) designed for children (or at least designed to be child-safe; anyone can play with it). It also looks like a robots head.
But the synthesizer has a single voice, limiting its composition ability. The obvious solution is to add a jack so the clock signal can be shared with additional units, but I didn’t think this fit with the child-friendliness.
So I came up with the idea of using infrared to synchronize multiple units wirelessly; but how to do this without a lot of complexity and with a suitable “user interface”?
The solution I came up with places an infrared transmitter and receiver in the eyes of the robot face. Under normal operation one eye transmits the clock pulse and the other eye receives it providing the clock for the “local” sequencer.
To synchronize units, the emitter eye is covered with an eyepatch (pirate mode!) or eyelid (wink!) and the face aimed toward the “lead” unit. The infrared clock pulse is then received by the “winking” unit and they will play in unison.
This should work for several units so long as the infrared source is strong enough and there’s not too much stray infrared light (like the sun).
It opens some additional doors as well. Since the sequencer is driven by the infrared receiver, it could be “clocked” by any source of infrared pulses. This could be something electronic (like a television remote) or something organic like sunlight filtering through leaves blowing in the wind.