The device should beep with each heartbeat. The first device I got didn't beep no matter what I tried. Turned the beeper off and then back on again. Turned the device on and off multiple times. Tried six times and that's it. I sent it back for an exchange as the unit is well constructed and I hope I found one with a small defect among the thousands that came from the factory. And I hope that this defect is simply due to the sound signal and not the way he read the heart signals.
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