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.
This circuit can be used as a clok in digital applications. Power supply is 5-V and the pins for...
The MC15555 of this circuit is the old version of the common 555. What this circuit does is...
This circuit was indicated in an old American publication to serve as a Laser alarm system as a...