This circuit for automotive use was found in American documentation from the 90s. The circuit uses common components today. The relay is 12 V.
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....