Shake your phone

Can you explain how it works?

i can. noise creates a charge which the op-amp amplifies. the high input impedance of the op-amp and the low leakage current of the diode means the charge lasts a long time. everycircuit noise is always negative, but in real life the diode would dissipate the positive portion of noise-generated signals while allowing the negative to build up a small charge.

I do not understand why the circuit (simulation software)react when the phone is shaked. Anyway, thank you for the explanation.

Shaking your phone injects noise into the circuit. In real life, components themselves generate random noise (the British Premium Bond lottery uses random numbers created from the noise generated by Zener diodes, in fact). Components within the EveryCircuit simulator don't simulate noise, but if you shake your phone it will simulate some for you.

Forgot to add: some circuits, particularly oscillators, depend on a degree of noise to start oscillating. Normally you'd get this from component-generated noise or just from transients generated by switching the power on; the simulator supplies the noise in a different way.

Thank you very much Tonyinselby, good explanation.

everycircuit "noise" is after shake a portion of current over a short time, one or simsteps. The voltage at a 5pF cap is measure on top negative, depends on how EC drives the current portion to the component. about 30uA, depends on when the component was place while edit, (hashcode) builds up at 5pF over one simstep 800V !!!! this keeps forever constant as @eekee explains, cuz the input impedance of opamps is infinite within EC. 15V is maximu from opamp out and with a resistor it lightsup the LED till the key reset the charge of the capacitor! http://everycircuit.com/circuit/5895611468218368

lumine72 : sorry to be back so late. eekee, tonyinselby, hurz : thanks a lot for your explanations. Now, I just have to go back to bathe and take a nap 😋😎😄

You're welcome! :D