f=1/(2*pi*sqrt(L1*C3))i don't understand how to calculate formula for output frequency f=?
How does change in air pressure change the inductance?AnalogKid, This circuit is ok. Many washing machine use this technical for detect level water (Ex. Sanyo, Panasonic...), when level water in washing machine change -> presure of air in the tube change -> value of inductance L1 change -> output frequency change.
When I use L1=220uH, C3=0.1uF ->F(caculator) = 33.9KHz but i use oscilloscope and measure F(measure) = 125.24KHzf=1/(2*pi*sqrt(L1*C3))