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Re: And we thought the text part of the Starr Report would be bad


From: "Roger Fajman" <RAF () CU NIH GOV>
Date: Thu, 24 Sep 1998 00:45:39 -0400 (EDT)

    For modem to modem communications, start and stop bits were used
    up through 2400 baud when one bit = one tone.  The method of one
    bit = one tone was dropped for other forms of encoding when modems
    started supporting connection speeds in excess of 2400 baud.

I assume you mean 2400 bps modems, i.e., v.22bis?  Admittedly, it's been a
while since I used one, but my recollection is that 2400 bps modems operate
at 600 baud, with 4 bits/baud using QAM.

This matches my recollection.  I think it was 1200 bps that was the
last 1 bit per baud modem.

Cheers,
-- jra

Yes and no.  The Bell 202 was 1200 bps, one bit per baud, half duplex
on a switched line.  The Bell 212 was 1200 bps, 600 baud, 2 bits per
baud, full duplex.  So was the Vadic 3400, which preceded the 212.


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