11 Jul
1997
11 Jul
'97
9:41 a.m.
Marvin <marvin(a)rain.org> writes:
Just curious (again!) if anyone is collecting the
early modems used on
computers and what might have been the earliest commercial phone modem.
I have a few, but not what I would call "early". An old Omnitec 701A
(s/n 3) acoustic coupler that I used to use with a Teletype ca. 1978
(still worked when I tried it about a year ago, too). Also some S-100
modems, including a couple each of PMMI MM-103 and Hayes Micromodem
100, and what I am guessing is an earlier (1978) effort by D. C. Hayes
called the 80-103A.
I have several devices that are called modem
eliminators and I believe
these are basically serial cable boosters to increase the permissible
cable length.
It depends. They may also provide clock signals for synchronous DTEs
(as would ordinarily be done by the modems).
-Frank McConnell