Wirt Atmar wrote:
>[Bruce Toback wrote:]
>>  Prior to RS-232 -- and for quite some time
>>  afterward -- most terminal serial connections used a 20ma or 60ma current
>>  loop.
>
>John Korb wrote privately and pointed out the same thing. He also pointed out
>that current loop to voltage converters were available during the conversion
>period to RS-232.

They still are. The Black Box Catalog has not one, but three different
RS-232-to-current loop converters, starting at US$65. There's even a
16-port version, if you have to hook up *lots* of Teletypes. :-)

-- Bruce


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