On Mon, 16 Nov 1998, Paul B. Webster VK2BZC wrote:

> There is only *one* way, and a very good way to block cellular phones,
> but it is only applicable to when the hospital is built.  It has
> valuable side benefits.
>
>   Screen everything (including the windows!).

I'm sorry to disappoint you, but we have a storage room here to keep
valuables in, and it's entirely metallic, about 5x2x3 m, welded mild steel
plates (about 5 mm), ditto doors, ceiling, and floor, and very few cables
going in (one: for the lights). I have to say that my cellular won't drop
a single notch on the S scale once inside, with the doors closed firmly.
Monkeying with ferrite suppressors for UHF on the electrical cable
pass-through didn't bring any relief either.

BUT I have built a cellular detector in 1996, used to mute a car radio
when the cellular is in use, and I imagine that a suitable device could be
used for hospitals. It may sound a continuous low volume alarm whenever
someone is near such a device. This would force a cellular user to get out
or hang up very fast.

Peter