Hi
I want to use my Arduino to measure the level of fuel in our oil fired central heating tank. I have seen commercial devices that use ultrasonic transducers and thought "i can do that". To get around the problem of the transducers being affected by moisture etc I thought I could use the sensors from car parking sensors as they must be at least moisture proof as they're mounted on car bumpers. The problem is I'm not entirely certain on the circuit to drive the transducers, I seen several that use a 555 to produce the output and some kind of op-amp to amplify the input. Has anyone else tried this or have any good ideas or suggestions.