This circuit was found in July 1975 Radio Electronics magazine. Power depends on the trigger transistor and the effects of capacitors C1 and C2.
This circuit allows 220 / 240V shavers to be used in the 110V network. The diodes can be general...
Used with telephones at the time, this circuit was found in Popular Electronics from the 90s. The...
This circuit was obtained from an American 80's documentation. It can be implemented with modern...