This symmetric 30 mA x 15 V power supply was found in the Ferranti transistor manual from 1974. Transistors are common types at the time.
This circuit was obtained from a 1994 publication. Its purpose is to digitally switch 5 audio...
The circuit shown is from the National Semiconductor's Linear Applications Handbook. The CI is not...
In this charger, the charging current is basically limited by the LEDs. The transformer is a low...