Yep, that's exactly how it works. We've had only 2 false alarms, both times in the middle of the night when I'm fast asleep and so scared the crap out of me! DS was oblivious to it all both times and gave me a funny look when I picked him up out of the cot

The only thing that bugs me about mine is on occasion the parents unit makes a brief "shh" sound like white noise for about a second. I have no idea why but doesn't seem to affect anything about the monitor.