| Re: History of Hayes Modem |
|---|
I'd suggest investigating the history of:
"voice frequency telegraph" (a-k-a "voice frequency carrier telegraph")
technology which is officially defined in various standard glosaries as
'A method of multiplexing one or more dc telegraph channels onto a
nominal 4-kHz voice frequency channel.' Sounds like a modem to me :-)
In fact, I would contend that the earliest practical 'modems' were to be
found in the context of the "harmonic telegraph" ... see this brief
interesting article [for example]
http://www.telegraph-office.com/pages/harmonic.html
dating back to early 1880s. The previous work of Elisha Gray and his
'electro-harmonic' (or 'electro acoustic multiplex telegraph') is
referenced there. Also, it appears that Gray's competitor Alexander
Graham Bell did some seminal work in this area too based upon
http://repo-nt.tcc.virginia.edu/book/chap3/chapter3sec4.html