🚀 go-pugleaf

    Not at all- the thread is still about whether a mobile phone (or other
small, similar transmitting device) can damage other electronics devices.
They can.  Other posters and I have given some examples that other readers
can duplicate.  This isn't about noise per se, it is about induced signals.
    A cellphone far from a tower can go to "high power" mode- four or five
watts.  Next to a CD player, a small transmitter with this sort of output
power can easily disrupt operation so that the unit must be powered down to
recover.  Some laptops with 3.3 volt processor cores can break into
"internal SCR" mode and burn out.  Many consumer devices can easily be
damaged by close proximity to such an RF level at the frequencies that
cellphones operate at.

>   No properly designed electronics should be damaged by a mobile phone OR
by
> being adjacent to the powerful mobile phone base station.  This kind of
damage
> is so easy to avoid.

    I agree with your opinion, but the catch phrase is "properly designed".
It becomes increasingly difficult to make cheap consumer electronics
"bulletproof" when we are each running around with a miniature microwave
transmitter shoved up against our head.

> The amount of energy induced into leads and PC traces is
> far below those implied in this thread.

    The average energy of the signal is low, sure.  The impulse levels are
not so tame.  And when a loop of wire printed on a circuit card or routed
through a case picks up a field with a density of 10 volts per centimeter, a
10 centimeter wire can "see" impulses of 100 volts.  Each junction is no
longer isolated also- in the ICs, each represents a tiny signal detector.
On top of that, there are parasitic junctions on the die- unintentional
"ghost" diodes and SCRs that can (when improperly stimulated) break into
conduction and continue to conduct once the signal is removed.
    If power is removed, they can switch off and operated normally most of
the time.  If not switched off in time, they can become tiny heating
elements or short circuits that will destroy the operation of the device.
    Now, imagine that a transient impulse of 30 volts is deposited at the
input of a CMOS logic gate that is operating on a 6 volt Vdd- many times,
the typical ESD protection will handle it nicely, but what if that transient
appears at the Vdd terminal?  You can't be certain that the device will
survive.  And at cellphone frequencies, you can get well isolated local "hot
spots" that can easily exceed 30 volts.
    Run your cellphone right next to your laptop or CD player next time and
see what happens.

Cheers!

Chip Shults

SPAM free Email - aichip@gdi.udu.net but remove the .baryon