[barrkel]

Our baby monitor uses DECT - it's basically a cordless telephone. While I wouldn't expect it to be encrypted to any significant degree, in most cases a baby monitor is either broadcasting silence with a little background room noise, or it's turned off. Once a monitor starts broadcasting noise, a parent intervenes.

[giantg2]

Some of them are even VOX so that it's not continuously transmitting.

I think the concern (fun for the scanner) was that if people leave the monitor on all the time and then have a conversation in that room.