> Any time that you saw a piece of
> equipment with a DB-25 connector on it, it was almost certainly a RS-232
> connection.
Not entirely true - in fact, probably a dangerous assumption! The D style
connectors date WAY back, when computers used tubes!
Agreed. The maximum voltage for a D connector (at least a decent one) is
something like 500V. A lot higher than most people expect.
Main
problem is that the Amphenol connector is too wide to properly fit
on a standard IBM card bracket (yes, OK, they should have made the
bracket wider...)
Can you fit two DB connectors on a card bracket? That may be one reason
they moved the RS-232 to the DE style.
Exactly. The serial/parallel adapter came out with the AT - and that was
the first use of the DE-9 serial connector. And no, you couldn't fit 2
DBs on a bracket. You can _just_ fit a DA and a DB on the same bracket -
I've seen multifunction cards that do that. Problem is, the IBM case has
a lip (so you don't scratch your hand on the board fixing screws) that's
not in most clones. Getting the plugs into one of those cards on a real
XT is interesting...
The older 500v capable D connectors had solid pins though of a heavier guage. Has
anyone noticed that many of them are lightweight guage and in some cases hollow?
This drops the voltage and current capacity way down. I just repinned the
connector on a VT 130 terminal for a local business and noticed the difference in
the old pins and the new ones. You bend a new one and it breaks, and old one can
sometimes be straightened unless it's kinked (and then cracks).
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Russ Blakeman
RB Custom Services / Rt. 1 Box 62E / Harned, KY USA 40144
Phone: (502) 756-1749 Data/Fax:(502) 756-6991
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