[sdiy] optical theremin, 555 cool stuff (it's all in the duty-cycle)

[Mikael Mørup]

Citat anthony <aankrom at bluemarble.net>:

> Here is a good optical theremin circuit: (Hey did I find this link here?)
> http://www.baragon.8m.com/555.jpg
>
> Don't build the lumivox the way the schematic / picture shows it.

Lot's of people from the (circuit)benders group build it, and i have yet to hear
about one who made the LDR controlled volume work. Pitch work reasonably well.

Someone with a better understanding of electronics than me can surely explain
why - my guess is something like an 8 Ohm speaker getting all choked from the
much higher resistance of the LDR, a simple transister amplifier stage might
work wonders here.

Mikael