Can somebody help me understand how this circuit works, why it oscillates and what the conditions for the oscillations mean?

Frank Watt asked Jan 20,2021
0

I'm fairly new to electronics, accidentally made an oscillator with this circuit. As showed in the pic, R5 would be an 8 Ohm speaker, or otherwise there could be an LED to show the oscillation. The transistors I used are basic NPNs (S8050).

As far as I understand, the reason why it oscillates should be that it's quite an unstable circuit, C2 charges rapidly but when it reaches a certain voltage, it shuts off Q2. Then it discharges on R6, with a time costant R6*C2 (which is partly responsible for the oscillation frequency), and when the voltage drops below a certain level, Q2 opens and the process repeats. However, I have no idea what the role of C1 is.

r9.1.jpg

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