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 circuit was found in a 1995 documentation. It drives a set of sequential LEDs from the sound...
We found this modulated oscillator in a 1956 publication in Sylvania. The transistors are from...
Found in 90s Radio Electronics, this small transmitter has a good range. L1 is formed by 3 + 3...