File:Neon bulb oscillator circuit.svg

English: Circuit of a Pearson-Anson oscillator, a very simple type of relaxation oscillator which uses a neon bulb N as a switching device with hysteresis. The voltage source V_S charges capacitor C through resistor R. The neon bulb has a very high resistance until the capacitor voltage reaches its breakdown voltage V_br, at which it conducts and discharges the capacitor, and the cycle repeats.