Posted on Jul 18th 2011
Here
is an isolated Line Voltage Power Switch/Dimmer designed and built by
Charles Wetzel, one of our users in Austin TX. It is arelatively easy
and inexpensive circuit, built with all through hole parts and a $5.00
SchmartBoard 201-0001-01.
"This line voltage power controller interfaces a DC control voltage or
microprocessor logic output to an AC load. By adding a filter capacitor
to the input resistors, the circuit may be controlled by a duty-cycle
modulated square wave with about 2.5 volts average giving minimum
brightness and 3.5 volts average giving full brightness."