This receiver for a modulated light intercom was found in a 90s Elektor. The audio amplifier can be replaced by an equivalent. The sensor can be any phototransistor.
The presented circuit provides an output voltage proportional to the input current, according to...
This circuit can be used in bridge of sensitive measures. We found it in a documentation from the...
This circuit provides a high intensity pulsating signal to a speaker. The circuit is from an...