This PLL with operational amplifiers was found in 1969 documentation. The configuration can be adapted to use modern components. The circuit has a gain of 15 V / V and can operate with 10 kHz signals.
This circuit triggers an oscillator when any of the sensors is opened. The circuit can be powered by...
This circuit imitates the singing of a bird intermittently with the intermittency determined by C1...
This is a high gain circuit with 3 transistors connected in direct coupling. The circuit is from a...