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Ultrasonic sensor controled directly from arduino? Answered

I'm on a time crunch for a project, and I want to have distance sensing.  Unfortunatealy, i dont have enough time to get stuff shipped, nor the budget to use radioshack.  I was wondering if I can use a single pieze transducer without premade circuitry, and control it from an arduino. 

I have some transistors, some common ICs (386, 555, etc), and basic passive components, plus two arduino UNOs (one with a broken FTDI adapter) can it be done?
I don't need an  exact, continuous, or scaling measurment, just one that gives me an idea of the distance/presence of an object. 


Try it: Its not easy, but its potentially do-able. You know how sonar works, you have to work out how to start a HF oscillation, stop it, wait a millisecond, and then listen for the return. There are gotchas at almost every stage of the process, but you MIGHT be able to get something from it.

Don't start and stop the 555 to create the ultrasonic signal, pass it through an AND gate and switch that with the processor. You will want to turn the piezo from a speaker into a microphone, and you switch that on with the same sort of logic.


It takes specialized speakers to produce ultrasonic sound. You won't be able to use a piezo for this.

Yes, I know, that's what I meant by metal can/piezo. It used to have an attached circuit, but an IC blew and I removed the transducer. Thats why I'm trying to see if I can use an arduino without the board with the piezo transducer (it is a type of piezo, just specifically designed for that purpose)

Sorry, i meant piezo (not e), and I mean I don't have any circuit attached, JUST the metal can-thing with two leads.