Why does an Ekasi oscillator oscillate?
From my research, I learned that when this is first plugged in, the capacitor is charging, so the LED doesn't shine.
When the capacitor reaches 12v, then the current switches to the top loop (which is possible because the voltage of the battery equals to the breakdown voltage of the flipped transistor). Note, because we are using its breakdown voltage, the base doesn't need to be connected.
As for its oscillation, I read that when the current goes through the top loop (and the LED is shining), the capacitor begins to discharge. So, because the voltage across the capacitor goes down, the current stops flowing to the top loop and goes back to the capacitor to recharge it (so the LED stops shining). This repeats, creating an oscillation/blinking LED light.
My question is: why would the capacitor discharge after it reaches 12V? What causes it to begin to discharge? Is it because when it's fully charged, no current is flowing towards it, "preventing" it from discharging? So it's free to begin discharging, but as soon as it does, then it begins to slowly recharge once again, creating this repetition? Sorry if it's a bad question folks, I just recently got into electricity! 🙂
Here's the schematic:
simulate this circuit – Schematic created using CircuitLab
Edit: Added resistor to circuit.
Best Answer
First, the circuit as you present it is a bit too simple -- the resistor in series with the battery as shown on this page is necessary, and must be about the right value.
Second, the reason the capacitor will discharge (in the correct circuit) is because the LED-transistor string is consuming more current than the battery (through that resistor you left out) is supplying -- so the capacitor discharges.