[cctalk] Re: RS232 then and now

[Paul Koning via cctalk]

> On Jan 31, 2025, at 6:19 PM, Cameron Kaiser via cctalk 
> <cctalk@classiccmp.org> wrote:
> 
> 
>> Low speed modems are just analog devices that can pass any signal up to 
>> whatever the design speed limit is.  For example, a 103 modem is good up
>> to 300 bps, but will happily carry anything less.  A 202 modem (see 
>> below) is designed for 1200 but also will work at lower speeds, and has 
>> been used at 1260 bps.
> 
> I'd argue those are differing situations, though. Bell 103 and Bell 101 modems
> use the same AFSK frequencies, just at different speeds. Bell 202 modems have
> specific hardware to support Bell 103, effectively two modems in the same 
> case.

That's not the case for the 202 modem I have; it is definitely 202 only and 
does not offer 103 compatibility.

        paul