This circuit multiplies the input voltage by 3 and can work with up to 12 V input. The current is a few mA. We found it in the Radio Electronics magazine of December 1992.
The integrated circuit used in this 80's application is not common today. However, modern...
According to the consulted American publication of the 1980s, a zener diode can be used for DC...
This circuit, found in an American publication from the 1970s, produces an audible tone in a...