This circuit protects the speaker from dangerous direct currents that could damage it. The circuit is from an Electronics Experimenter Handbook 1993 edition.
Published in 1988 in Hands-On Electronics, this circuit converts the 12 V of a battery into 120 V...
This circuit was found in an American technical manual from the 1980s. The LM111 is an uncommon...
This circuit was obtained in an American publication of the time. Transistors are commonly used. The...