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While I am not the Campus's telecommunications engineer (I refer that to
Bob Gress), I would say that the reports are more urban legend/rumor
than fact.

WiFi (a/b/g/n) are considered FCC Part 15 radio devices.  This means
that they MUST accept all interference, and it must only broadcast on a
very narrowly tuned set of frequencies.  Certified wifi antennas (those
that ship from the manuf) are tuned to receive and send at the
2.4GHz/5GHz range that WiFi is set to operate.  This could be changed by
using custom-made/home-made antennas that don't account for unshielded
wire-length, etc.  WiFi devices (at least the Cisco devices I know of)
do not have any speakers or components that could cause sound to really
be formed. 

FM Stations are at typically broadcasted at 87000.5 kHz to 108000.0 kHz,
with stations taking 100Mhz.  AM Stations are typically broadcast at 520
kHz to 1610 kHz with 10 kHz spacing.  802.11b/g are in the 2400000 kHz
range.  (These are listed in kHz to show the difference in frequencies).
Since these ranges are not close to the WiFi range, sound bleeding into
the WiFi range is not likely.

Now, given that computer speakers will accept certain types of
interference it is conceivable that they can accept certain frequencies,
especially if they are very powerful (lots of wattage).  This is common
with many cellular telephones and two-way radios.  However, radio
stations will usually not have that amount of power, unless you are in
very, very close vicinity of the broadcasting tower.  Speakers making
noise from these devices is a result of the air-space around it either
interfering with the electronics directly, or causing the magnets in the
speaker to vibrate, causing the sound.

In theory, with a wire/antenna long enough (or exactly at the right
length) connected to a speaker, or some sound-emitting device, could
play the radio.  This is the theory behind a crystal diode receiver.
There is a lot to go exactly right for this to work.  Chances are that
the "music in the work room" is more related to an actual radio in an
adjacent room.

Now as far as their questions about the computers -- this could simply
be a CD left playing in the CDROM, or some sort of device plugged
directly in to the speakers.  I have an XM radio receiver that I use for
entertainment during the day.  That device required no program running
for music to be sent to the sound card (a program is used to change
stations, however).

-Nick Kwiatkowski
 MSU Telecom Systems, P&E Group





-----Original Message-----
From: MSU Network Administrators Group [mailto:[log in to unmask]] On
Behalf Of Hoort, Brian
Sent: Friday, January 11, 2008 9:31 AM
To: [log in to unmask]
Subject: [MSUNAG] FW: Wireless laptops picking up local radio stations?

Given our recent discussion at this week's NAG meeting regarding wifi
anomalies, I thought this post from another list was pertinent and worth
sharing here.  May I request that someone set up an on-line voting
system so that we can choose between The Impact or WKAR?

Brian Hoort


-----Original Message-----
Sent: Friday, January 11, 2008 8:55 AM 
Subject: Wireless laptops picking up local radio stations?

Hello all,

About three years ago, we heard feint music & voices from the closest in
our
work room.  To our astonishment, the music was coming from our Cisco
wireless access point and seemed to be a radio station of some sort.  We
had
no explanation but thought it  interesting, especially since the AP does
not
have an internal speaker to reproduce any sound.

Two days ago, a teacher brought in a Dell D630 laptop with was playing
jazz
feintly through the speakers at the Windows desktop.  There was no music
software running at the time, as I checked the task & process list.  The
jazz was quite nice, though.

And then today, another teacher showed me his HP Tablet PC.  It was at
the
login screen playing some kind of easy listening music.  Since it was at
the
login screen, no software could have been loaded at this point, unless
it
was a service of some sort.

These instances aren't really problems per se, but they are extremely
interesting.  Do wireless antennae pick up radio signals and somehow
amplify
them?  Has anyone experienced anything like this?  Or perhaps we are
experiencing the first stages of paranormal activity at Wayne College.
:)

Thanks!
Tom