This sophisticated workbench power source was found in 90s Radio Electronics. The maximum current is 15 A and the voltage can go to 37 or 42 V output.
This experimental amplifier was found in the 1960 Mullard transistor reference manual. The...
This circuit from Motorola is from 1968, appearing elsewhere on this site. The transistors admit...
This circuit triggers the LED when the monitored battery voltage drops below 9 V for 12 V...