This 5V power supply with a 1.5 to 3 A current was found in Maxim documentation from the 90s. The integrated circuit is the MAX741D.
This well-known siren configuration using complementary transistors is from a 1980s documentation. The...
This circuit was found in an old American magazine and could make use of more modern components...
This circuit is from the Philips integrated circuits manual of 1990. It is intended for magnetic...