How do I wire a three-terminal piezo buzzer to make it sound?

I salvaged a piezo sounder from a CO detector.  The sounder (EFM-290ED rated at 9V) has 3 pins rather than the two I am more familiar with.  The pins are labled G, F, and M.  I have tired applying 9V across all combinations of the pins but haven't had any luck maiking it sound.

iceng2 years ago
Try the 2N2222 version.

3t piezzo.gif
Great for getting a teenager out of bead in the morning.
Needs a oscillator to M (main) and G(ground)
F (feedback) is for a feedback oscillator.