tony roberts wrote:
It is an FCC rule because cellphone tower are designed to
pick up a limited number of calls and at altitude the towers
are over-loaded.

I don't understand this.
Consider that many new headsets actually have a cellphone interface.

and consider that here in Canada it is not illegal, and I use mine lots
- plugged right into my headset.
I don't understand how it could be legal here if it really did overload
towers. So what is the REAL reason?

Hmmmm . . . the plot thickens


I have heard that the real reason is that the towers are overloaded -

- with handovers.

The call has to be handed from tower to tower as the user
moves. The system was designed to cope
with walkers, people in cars, but not jets at 600mph.

I have no idea if the above is really true but it does make
some sort of sense to me.

On a related but unrelated topic -

One of the mysteries of life is that you can be in say London,
turn off a mobile phone, put it in a bag and go to Sydney.
When you get there you turn the phone on and if a few seconds later
your boss in Moscow calls you the call can be successfully routed
and your phone rings.