The Photo Trans-Activator is a project that has been in the works , on and off,  for a couple years.  I finally decided to wrap it up.  It was basically a matter of how far I wanted to take it.  This is my most complex build to date.  Here’s how it sounds…


This is built around 2 photo resistors.  Actually one photo resistor and one solar sensor.  Both effect each other in interesting and unpredictable ways.  The variety of sounds this thing produces is limitless.
The layout of the controls
ready to bend the metal control panel

ready to bend the metal control panel

It’ll produce a steady tone that can change pitch or it’s produce wild growls, bleeps, distortions, squeals, and other random chaos.  This is highly effected by light and is most powerful when played in low light situations.  I’ve also included the option to remove the light sensors and instead control those modulators with knobs.

The holes have been drilled, time for paint.

The holes have been drilled, time for paint.

There’s also an effects block.  This was created from a toy voice changer that has 3 effects, Ring Mod, Robot, and Alien effects.

Final assembly

Final assembly

There’s also a strobe circuit incorporated into this box.  The light is flexible so you can point it at either of the light sensors.  You can adjust the speed, and brightness of the strobe.

Completed

Completed

View the full  Photo Trans-Activator gallery