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Printer Sounds Revealing the Words Printed  (View post)

Roger Browne [PersonRank 10]

Sunday, June 7, 2009
15 years ago3,893 views

When I started University in 1976, there were no monitors. The command-line sessions all took place on DecWriter terminals. These were pin-based dot matrix printers operating at 300 baud (approx. 30 characters per second).

We soon learned to recognise certain kinds of printout by sound. The Unix command prompt was pretty distinctive, and if someone was away from their terminal when their job finished, we would recognise the distinctive sound and call them back.

Certain frequent error messages were also easily-learned. We knew when a long compile had failed without looking, just by the sound of the printout.

Of course, printers are much faster nowadays and you need to analyse the sound by machine. But decades ago it was already possible to "hear" the output of a printer.

Waldir Pimenta [PersonRank 2]

15 years ago #

This reminded me of a post I read some time ago in Hack a Day: Sniffing keystrokes via laser, power lines

Now wouldn't all these techniques make a great plot for a heist film? :)

David Sanger [PersonRank 7]

15 years ago #

Back in college I remember one of the early hacks was to invert the process and make a document that when printed on an IBM 1403 chain printer sounded out "Jingle Bells"

Ludwik Trammer [PersonRank 10]

15 years ago #

Wow, you never know where the vector of possible attack will surface. I submitted the article to digg:

Steve [PersonRank 0]

15 years ago #

So for security reasons isn't it just as well that DMP (dot matrix printers) aren't in wide circulation. Next up, the sound of a laser or desk jet output able to be analysed. I'm being slightly tongue in cheek here, but it wouldn't surprise me if that will be possible soon.

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