Recommended for automotive applications, this circuit was found in an April 1982 Radio Electronics magazine. The transistor supports equivalents. Sensitivity adjustment is made by R1.
This circuit was obtained from an old American documentation having a limited adjustment range....
The movement of the LEDs in this circuit mimics the back-and-forth movement of a pendulum, making it...
This circuit is from a 1967 documentation. It makes use of varicap and diode tunnel in addition to...