This PA or Public Address amplifier with a few watts of power was found in the March 1986 Radio Electronics magazine. It uses two LM380 ICs in bridge mode for higher power.
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...