This circuit came out in a 60s RCA documentation. The circuit uses common lamps and LDRs but can be implemented with LEDs.
This common emitter amplifier with 43 dB gain was found in the August 1970 issue of Radio...
This circuit was found in a technical documentation from Texas Instruments, using a...
We found this circuit in a 1980 publication. It can be applied to Triacs of the TIC series and the...