In article , Frank Slootweg
wrote:

Putting the coupler in a suitcase was not a big burden

...you would have needed a laptop back then anyway.

Is this/he for real!?

When you were using/carrying the acoustic coupler around, did you
have/use a *laptop*!? It was most likely a 'portable computer', FSVSVO
'portable'. ('Mine' had to be carried by two people and that was only
the computer, never mind the peripherals.)

that would not have fit in his suitcase

BTW, I couldn't find an introduction date for RJ11, but I'm quite sure
that our acoustic coupler didn't have it.

no reason why it would have one.