This circuit is from an old RCA documentation. The circuit sources a charging current of 1 A and is intended for the 6 V lead acid battery used in some cars of the era.
This circuit was found in Motorola documentation from the 1980s. PUTs are not common components...
This low distortion circuit was found in a 1964 Electronic Design. The transistor admits...
This circuit is based on an uncommon Texas component today, as found in an American 1980s...