We found this circuit in the March 1980 Radio Electronics magazine. The circuit used is the HA2400 released at the time. The power supply must be symmetrical.
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...