By 1970-71 the US Air Force was testing its own facilities for emanations,
and as a low grade enlisted person with a Top Secret/Crypto clearance, I
was allowed to see the results of a test conducted against a facility
where I worked. The site used KY-8's and KY-28's, and we thought we were
very secure. The people in the Tempest van read us like a book, having
picked up signals on the way to KY's.
I got the impression Tempest was fairly well institutionalized by then, at
least in the USAF, and that some of the old hands had seen this before.
I can't recall whether the term 'Tempest' itself was an acronym, although
most sources now say it was not (e.g., online computer dictionary) but
these sources could be wrong.
On Mon, 24 Jan 2000, Arnold G. Reinhold wrote:
> Regarding the question of how far back TEMPEST goes, I took a look at
> David Kahn's "The Codebreakers" which was copyrighted in 1967.
> TEMPEST is not listed in the index. However I did find the following
> paragraph in a portion of the chapter on N.S.A. that discusses
> efforts to improve the US State Department's communications security
> (p. 714):
>
> "... the department budgeted $221,400 in 1964 for 650 KW-7's. ... The
> per-item cost of $4,500 may be due in part to refinements to prevent
> inductive or galvanic interaction between the key pulses and the
> plaintext pulses, which wire tappers could detect in the line pulse
> and use to break the unbreakable system through its back door. "
>
> This would be the electro-mechanical equivalent of TEMPEST and
> suggests that NSA was well aware of the compromising potential of
> incidental emanations long before the computer communications era.
>
> Another useful data point would be earliest reports about the BBC's
> system for detecting unlicensed television receivers. That system
> used vans equipped to detect a TV's local oscillator, but may well be
> an offshoot of emanations intelligence research.
>
> Arnold Reinhold
>
>
