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Circuit diagrams

This circuit has the LED columns alternate by the capacitors turning on and off the transistors (from a toy christmas tree). I've been trying to visualize it for a day now. I cannot understand how the capacitors are actually switching the transistors.

Care to help a beginner? P.S. Does this setup have a certain name? I can read up more on it myself in that case. Thanks.

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enter image description here

Found a great animation here: http://www.falstad.com/circuit/
(then choose from the menu: circuits/transistors/multivibrators/astable multivib

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It is basically an RC circuit. The capacitor is loaded through the resistor and the transistor works as a key. (Saturation and Cut-off modes)

When the capacitor is fully loaded, the voltage is enough to sature the transistor and turn on the LEDs. When it is discharged it cant sature the transistor and it enters in cut off mode, so the LEDs are off.

The ON and OFF time of the LEDs will depend on the frecuency of the RC circuit.

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