[jonas21]

> Even then, you couldn't actually electronically connect a device, you could only acoustically couple it. Direct connection of modems wouldn't be legal until the 1980s.

In the late 90s, I remember watching the scenes in WarGames (which came out in 1983) where Matthew Broderick's character is using a modem where you had to place the phone cradle on top of it and thinking why would you ever design a modem that way?

And of course the reason was to work around this stupidity.

https://youtu.be/zb1r_uKOew4?t=49

[wyldfire]

I didn't know this was the case. Interesting!

From [1]

> It was not until a landmark U.S. court ruling regarding the Hush-A-Phone in 1956 that the use of a phone attachment (by a third party vendor) was allowed for the first time; though AT&T's right to regulate any device connected to the telephone system was upheld by the courts, they were instructed to cease interference towards Hush-A-Phone users. A second court decision in 1968 regarding the Carterfone further allowed any device not harmful to the system to be connected directly to the AT&T network. This decision enabled the proliferation of later innovations like answering machines, fax machines, and modems.

From [2]:

> After the ruling, it was still illegal to connect some equipment to the AT&T network. For example, modems could not electronically connect to the phone system. Instead, Americans had to connect their modems mechanically by attaching a phone receiver to an acoustic coupler via suction cups.

[1] https://en.wikipedia.org/wiki/Acoustic_coupler

[2] https://en.wikipedia.org/wiki/Hush-A-Phone_Corp._v._United_S...

[foobiekr]

Acoustic couplers also existed because most homes were pre modular phone jacks and the phones were connected with screw taps.

[salamandersauce]

It's not entirely stupidity. Acoustic modems also made sense for portability. Reporters in the 80s used to use things like TRS-80 Model 100 + an Acoustic modem to send stories back to the office over public telephones rather than have to hunt down a phone jack somewhere.

[josephg]

Australian here. I remember that scene, and I’ve always wondered what that was about too. I was using modems in the mid 90s and I never saw anything like that cradle device! Thankyou. That makes horrible, awful sense to me now.

[djmips]

Yeah, looks like acoustic couplers were mostly a seventies thing