This circuit is from a Radio Electronics magazine from July 1979. It uses the well-known IC 7107, a liquid crystal exciter that became popular in circuits of this type at the time.
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...