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ultrasonic range meter circuit?
I am building an ultrasonic range meter circuit, and it works perfectly around 10,000 hertz, but if I try and go to ultrasonic levels, my circuit doesn't work at all. My circuit consists of a simple op-amp setup with no capacitor or filters. For transmitters and receivers, I am using simple audio transducers that were not built for ultrasonic frequencies. I suspect that my transducers are the problem and don't work at all at these frequencies, but I'm not sure. Any input, guys?
You are correct in your assumptions....
Use ultra sonic transducers
http://www.allelectronics.com/make-a-store/item/XDR-24/ULTRASONIC-TRANSDUCER/1.html
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