🚀 go-pugleaf

        At the risk of showing my age !!  These signs were created before
Transistors were invented circa 1948 ! At that time, it was quite common for
Mobile transmitters to run 100 to 1000 watts output in the Short Wave Bands
. . At these power levels it was quite possible to ignite blasting Caps
wired at a blasting Site ! Hence the Warning Signs to shut off the Mobile
Transmitters  at these constuction sites, and coincidentally at fuel Depots
! In the intervening 60+  years, we now seldom use Hi-Powered  mobile
transmitters, with the exception of a few misguided CB operators, even most
taxi's transmitters are under  50 watts. Our latest Cell Phones are all
under 1 watt, and operate in the UHF bands. In the Good Old Days, it was not
uncommon to get an RF burn off  of the transmitter's   microphone,  never
mind from the antenna !  Nowdays we transmit with the cell-phone antenna
pressed up against our ear!  What we are seeing  are Warning Signs from the
Vacuum Tube era posted in the  PC age, and it doesn't really make much
(any) sense at all, until you realize that these signs and rules and
regulations were created three generations ago to cover situations that no
longer apply.  You will occasionally see these signs posted in a room, right
next to the Staff Microwave Oven !!

        Yukio YANO

coincidentally  VE5 YS


"Adam" <hideo@tne.net.au> wrote in message
news:3b04d952.4676022@news.tne.net.au...
> Most of us have seen the warning signs at petrol stations telling us
> to switch off our mobile phones. Obviously, some people believe that
> the transmission from a mobile phone is powerful enough to induce a
> spark in a nearby object.
>
> What about sensitive electronic componentry thats particularly
> susceptible to electrostatic discharge? If a mobile phone is operated
> near such equipment/components, is there a risk of damage? Can the
> signal couple with a loop on a PCB and induce a voltage capable of
> destroying a sensitive device? eg. If you're modifiying your computer
> & receive a call on your mobile, is it actually possible to screw up
> your motherboard if you get too close to it?
>
> I've spoken to an Electrical Engineer about this, and we were unable
> to discount the possibility. If anyone knows more, please contribute.
>
> Thanks,
> Adam Gerlach.