This General Electric circuit produces pulses of light only when light stops shining on the sensor. Equivalent SCRs can be used and the trigger adjustment is done in a trimpot. The maximum load is 40W.
This configuration is from a 1964 US documentation valid for any FET. The range of power voltages...
The operational amplifier used in this circuit from a 1970s publication is no longer easily found...
This circuit was found in an old American documentation. It can operate with signals from 40 Hz to...