On Thursday 03 January 2008 11:04, Mr Ian Primus wrote:
Something
might be loading it down, too. I'd check
for that before assuming it's bad.
Yeah, like maybe a shorted 1488 :)
I don't recall too many of those with that failure mode...
See what else uses -12v, and work from there. For what
it's worth, I've
replaced quite a few 1488/1489's - they typically get zapped in terminals
when people do stupid things with the serial lines while the terminal
is plugged in.
Like what sort of stuff? The most I ever saw those fail was one company that
had a wire running from one building to another and that used to pick up a
lot of transients from lightning. They'd bring those terminals in fairly
regularly.
I don't know if a failed one can short out the
-12v rail though. Never seen
it happen specifically, but that doesn't mean it can't.
I tend to not rule stuff out completely, and avoid surprises. :-)
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin