Billy Brown wrote:
>
> Harvey Newstrom wrote:
> > This is the basis of the old DoD Tempest requirements that government
> > secured vaults be lead-lined and have no external cables of any kind for
> > power or data. A simple truck body does not meet the requirements for
> > Tempest shielding.
> >
> > The ability to read computer screens and keystrokes via
> > radiowaves has been
> > around for decades.
> >
> > (Or so I've heard.....)
>
> That matches my information on the subject. Of course, it isn't very
> practical as a means of monitoring large groups of people. The monitoring
> systems I know about can only watch one screen/keyboard pair at a time, and
> have to be fairly close (within a hundred yards or so) to do it. This is
> stale data, so I'm sure they've improved a bit in the meantime, but
> monitoring large groups of people this way probably isn't practical yet.
>
> Hopefully, by the time it can be done we will have interface technologies
> that aren't so easy to monitor.
This data deals with air broadcast radiofrequencies. One area that is
not public knowledge, or what I haven't seen much of to date, are
signals transmitted in the sinewave harmonic patterns through the power
lines. These are quite present, and they can be amplified by a
surveillance system through use of a few simple components to boost the
harmonic output of the surveilled facility.
Mike Lorrey
This archive was generated by hypermail 2b29 : Thu Jul 27 2000 - 14:10:37 MDT