Found in 90s Popular Electronics, this circuit produces a modulated infrared beam for a remote phone whose circuit is shown right after it. Infrared LEDs are common.
We found this circuit in a 90s Popular Electronics. It increases the duration of a pulse in a...
This simple circuit detects when a conductive liquid reaches the sensors. The circuit has no...
This converter or inverter uses components that are still common. The transformer is the type...