Acoustic couplers, hackers and the rest…

Even though it might be a surprise for some younger readers – before you connected to the internet via wifi or ethernet there were these crude little devices called “modems”. And – unthinkable to many – before the modem (and long before the internet – yes even without the internet some of us went “on-line”) there even more obscure devices to connect a computer through a phone line – the acoustic coupler.

Acoustic coupler in phone booth
Iconic German hacker “Wau Holland” connecting to a remote host via an acoustic coupler in a public phone booth.

These weird devices looked a bit like a stylish stand for a phone handset. Like the actual handset they contained a microphone and speaker – just in the opposite order of the handset – giving them the ability to “talk” and “listen” to the actual handset.

That might sound confusing to the younger audience – i already hear someone mumbling like “Hell why not just plug a modem into the phone jack?”. The answer is simple – back in the early 1980s there usually was no phone jack – phones at home were just directly “soldered” (not really, but imagine they were) to a cable that came out of the wall. And even if you had a jack back in the days – the phone companys in most countries had  a monopoly and strict rules that were usually “it’s not allowed to connect any device not issued by us” in a nutshell. So the early adopters of computer communication had to fall back to such primitive devices – the acoustic coupler was born.

Obviously they came out of fashion when phone jacks became common and phone companies either lost their monopole or at least “issued” their own “seal of quality” modems.

However – some hackers still kept them since these were (and still are) the only possibility to connect when there is a handset but no phone jack. Like for example in a public phone booth. This was also used by some real black hat hackers for illegal actions since when you call a BBS or other remote host they can usually trace your phone number. If the caller is a public phone booth though that information was not so valuable. Today you may be behind a dozen proxies or an open wifi – but back in the days you were in a phone booth. These were the days.

Author: fronzelneekburm

Computer nerd

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