This high current switching stage was found in a 1967 EEE. The power transistor is from that time. The peak current can reach 30 A.
Found in a 90s Popular Electronics, this touch switch uses a single sensor. PLLs are common today....
This circuit generates both white and pink noise. The transistors can be BC548 and the power...
This circuit is from a 1969 Electronics World. The transistors may be modern general-purpose...