Found in American documentation from the 1990s, this circuit can generate signals of up to a few tens of megahertz. The transistor must be suitable for high frequencies.
This circuit was obtained from Radio Electronics from the 90s. The infrared sensor is of an...
The sensor in this circuit is a common transistor like the BC548. The circuit is from a 1979...
Although the UAA170 is not a common component today, the circuit shows how it can be used in a...