VBG!   Yup, RF sucks in some applications.  Even inductive loop systems wou=
ld have some leakage.
Still, I don't understand people like this.  Part of living in a free socie=
ty is being exposed to things you don't like.  But, that's another tag.
I do understand being annoyed at the wrong audio program.  You'd think that=
 they would change frequencies so adjacent theaters wouldn't crosstalk.

Back when I did alarms, (disco days) we settled on infrared, as all the oth=
er ultrasonic and microwave, and RF technologies penetrated walls and could=
n't be controlled.
Passive IR (thermal band, 10 microns) doesn't go through glass or walls in =
any significant way.=20


--=20
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