Typewriters symbolize key loggers?
"And in 1985 Soviet spies installed secret "keystroke loggers" and antennas in at least 13 typewriters in the US Embassy in Moscow to detect and transmit the typing patterns of embassy secretaries. The same technology is used more broadly today by criminals to steal passwords and credit card details."
https://www.telegraph.co.uk/news/worldnews/europe/germany/10968625/Can-typewriters-stop-spies-Five-things-you-didnt-know.html