This amplifier stage was obtained from a Popular Electronics from the 90s. The transistors are general purpose.
This circuit is from a Radio Electronics magazine from February 1962. It makes use of an old...
Microchip's MCP6411 Operational Amplifier can operate at voltages of 1.7 V and has a quiescent...
This circuit powers a small 5 W lamp that goes out when power is lost. The circuit can use the...