How a multivibrator Works
Électronique / Electronic

After you finish the wiring connections, put ON power. Look at the Meter-what's happening?

You see the Meter pointer rise quickly up, stay at a certain position and then quickly drop down. The Meter pointer stays at 0 for a few moments, and then the cycle repeats itself.

This type of output is called a square wave. Can you imagine how it got this name? (Hint: think of how a square looks ... straight sides, a flat top ... and now think of how the Meter pointer moves.)

Look carefully at this Project's schematic. You can see that it's a type of oscillator. But notice that the output is either on or it's off... there's no "in between!"

This means that a multivibrator is a digital circuit. 0 is when the circuit has no output while 1 is when there is an output. You can see that it's possible to control the operation of OR, AND, NOR and NAND gates using a multivibrator circuit.

You can also make a multivibrator operate at a different rate, try substituting 2.2K or 10K resistors in place of the 4.7K resistors used and see what happens.