Microphones

[LarryWilliams]

I have a hare-brained scheme to detect minor air
leaks using an ultrasonic microphone. Trouble is, I don't know where I can get one that will
operate between 16-50 kHz. Most ultrasonic
transducers are for a narrow range, e.g. 38-40 kHz. Does anyone have any suggestions? Thanx in
advance.

[Externet]

Hi Larry.<p>I would give a try to one of those Motorola piezoelectric speakers used as tweeters and pest repellent transducers. Somewhere I read their range is wider than any other brand. their specifications should be somewhere in the net.
It won't be small, unless you use the transducer alone discarding the plastic horn.
At least, one of these used as wide ultrasound source would allow qualifying other microphones suitability.
I have several Murata and another brand I cannot remember available, some are open air, others are sealed, about the diameter of a nickel coin.<p>Miguel

[chessman]

My suggestion is to use a small piezo transducer. When the piezo element flexes, it produces a small voltage. If you need any give me an email.

[viveguy]

Motorola makes some 1" piezo tweeters that are good out to 50 kHz.