Hello everyone,
When I was still a kid I got a "ScienceFair 200 in 1" board .... I didn't understand electronics but just wiring according to the numbers and playing with it was big fun! I rediscovered it 27 years later ;-) I recently started studying electronics in my spare time. It's a lot of fun but from time to time also hard as I don't know each component yet and the interactions occuring.
My question is about a basic oscillator circuit (in attachment). Based on the variable resistance it produces a short <beep> at a certain interval. What I don't understand is what triggers the discharge of the 3.3uF capacitor. I know when it discharges at the + side the voltage at the - side goes down as well (as is the case with e.g. a multivibrator circuit) and causes the transistor to switch off. When the capacitor is discharged the transistor base is again at 0.6V, it starts to conduct current again from collector to emitter.... and then I suppose the 3.3uF cap starts to charge... and when it's fully charged, what triggers the discharge? Is it due to the transformer which induces some reverse current when charging stops ???
Many thanks for taking the time to help me!
Best regards,
Dirk
When I was still a kid I got a "ScienceFair 200 in 1" board .... I didn't understand electronics but just wiring according to the numbers and playing with it was big fun! I rediscovered it 27 years later ;-) I recently started studying electronics in my spare time. It's a lot of fun but from time to time also hard as I don't know each component yet and the interactions occuring.
My question is about a basic oscillator circuit (in attachment). Based on the variable resistance it produces a short <beep> at a certain interval. What I don't understand is what triggers the discharge of the 3.3uF capacitor. I know when it discharges at the + side the voltage at the - side goes down as well (as is the case with e.g. a multivibrator circuit) and causes the transistor to switch off. When the capacitor is discharged the transistor base is again at 0.6V, it starts to conduct current again from collector to emitter.... and then I suppose the 3.3uF cap starts to charge... and when it's fully charged, what triggers the discharge? Is it due to the transformer which induces some reverse current when charging stops ???
Many thanks for taking the time to help me!
Best regards,
Dirk
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