This circuit, which is present in other points of this website, was found in a 90s Hands On Electronics. The circuit activates a buzzer with an oscillator.
From an old manual of unijunction transistors, this oscillator generates different tones when the...
A negative floating regulator capable of supplying an output voltage of -100 V with regulation of 20 mV for...
Found in a Hands On Electronics of the 80s, this circuit makes use of a gas sensor of the time....