Noises of dot matrix printers reveal printed contents

A team of scientists that has already informed about other unusual possibilities of espionage has now discovered a new method to obtain personal information: they analyzed the noises of a dot matrix printer and were thus able to reconstruct a large part of the printed information. Our suggestions against espionage using reflections and noises of printers are: no one should be able to look into it from "outside" (at a high level and/or cover by treetops; if reasonable, no window). In addition, do not use dot matrix printers. By the way, similar methods of acoustic recognition may be applied with regard to keystrokes. That's why you should avoid typing passwords and other secret information while talking to someone on the phone.