Hardware Hacking 87We can use a slight extension of this basic oscillator/LED/photocell design to
create a variation on our flashlight-controlled panner/mixer. The circuit shown
below uses one stage of the Hex Schmitt Trigger to make an low-frequency
oscillator; a second stage simply inverts the clock signal from the first, so the two
blinking lights are always out of phase -- note that one LED is always off when
the other is on. Use a Y-cord or clip leads to connect a CD player to both circuit
inputs and connect the two circuit outputs to two amplifiers; adjusting the
oscillator frequency changes the panning speed -- Psycho-Pan-Scan! Hook up
two different audio sources to the two circuit inputs, mix both circuit outputs to
one amplifier input (Y-cords or clip leads), and the adjust the oscillator to cut
between the two signals at different speeds -- Super Crab!