Found in a 90s American documentation, this circuit mimics the Enterprise warning signal from the movie Star Trek. The signal must be applied to an amplifier.
This old circuit for circuit breaker cars was found in a 1963 publication. The transistors are...
This circuit was obtained in a 1973 national publication, translated from an English publication of the...
Found in an October 1992 Radio Electronics magazine article, this circuit generates a low-power tone in...