[4534] in WWW Security List Archive
Re: ERM Surveillance Inform
daemon@ATHENA.MIT.EDU (Todd Nugent)
Thu Feb 20 14:02:21 1997
To: www-security@ns2.rutgers.edu (www security)
Cc: billj@i2020.net (Bill Joynt)
From: nugent@mail.chapman.com (Todd Nugent)
Date: Thu, 20 Feb 1997 10:02:02 CDT
Errors-To: owner-www-security@ns2.rutgers.edu
Reply
To: RE>>ERM Surveillance Information 2/20/97
10:10
AM
> I've heard some about this. Apparently first developed by the military,
> then copied by a company. Apparently the monitor emissions carry up to a
> block (one report said picked up by cables/wires).
I built one of these from a schematic in a magazine about 15 years ago. An
antenna and a simple circuit hooked up to the horizontal and vertical
magnet wires on the same model terminal would display everything on the
"slave" terminal which was displayed on the target terminal. The range of
my $20 device was quite good--200 feet--provided no other terminals of the
same scan frequency were operating nearby. However, modern radio emission
standards have drastically cut the signal strength of modern monitors
compared to terminals of 15 years ago. Also, with the increased popularity
of computers, trying to ease drop on a particular screen in a modern office
environment would entail an antenna/radio engineering and digital signal
processing project of significant magnitude.
There are still recordings floating around of classic music created by hand
coding disk head seeks and other RF noise activities to generate music on
nearby radios. I'm not sure if people no longer do this because they have
better things to do or because the emission levels are so low in modern
systems?
Todd
----------
> From: jwp@checfs1.ucsd.edu
> To: www-security@ns2.rutgers.edu
> Subject: Re: ERM Surveillance Information
> Date: Tuesday, February 18, 1997 11:22 PM
>
> > From: Matthew Petteys <matt@arcticmail.com>
> >
> > Does anyone have any information on a device that can be used to
monitor
> > the electro-magnetic radiation that a computer monitor emits.
>
