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3 Transistors, 5 Resistors, and 1 Capacitor. No need to shake to start. This circuit is also pretty stable and still functions well with low or high supply voltages.
How it Works:
On the fist NpN, the emitter is tied to a specific threshold through a voltage divider, and it turns on when the base voltage (controlled by the RC timer) rises about 0.7v above the threshold.
Of the voltage divider, There are 2 upper legs and 1 lower leg. The lower leg is the 1k resistor and is simply grounded, then the first upper leg is fixed to Vcc, and the 2nd upper leg is either floating or switched to Vcc through the PnP transistor (depending on whether the transistor is on or off at the time).
This effectively changes the threshold to a higher voltage when the NpN is turned on, and a lower voltage when its cut-off. The second NpN is simply just inverting the collector output of the first NpN. And lastly, the inverting NpN is what biases the base of the PnP.
*when the PnP is cut-off, the Capacitor discharges through the first NpN and the two far right most resistors*
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