Found in a Popular Electronics from the 90s, this circuit can act as a transmitter for an audio link. The output transistor admits a higher power equivalent, depending on the LED.
This configuration appears elsewhere on this site. We found it in a Motorola manual from the 70s....
The integrated circuit used in this small transmitter is not very common today. The coil has its...
We found this timer circuit in an American documentation from the 1980s. The circuit uses the 6 V...