27 Jan
2001
27 Jan
'01
5:43 a.m.
Tony Duell wrote:
[snip]
I believe the original IBM PC/AT had a resistor unit
that was screwed to
the chassis and connected to a drive power cable if there wasn't a hard
disk installed. I think it was a load on the 12V power line, which was
otherwise too lightly loaded (no hard disk spindle motor) to behave
properly. I've never seen this device, and it's not shown in the techref
(only in the HMS manual), so I can't be sure.
It decidedly existed. The first AT I owned arrived sans hard disk; when I
went to install same I just about fell over laughing when I found the
load resistor -- mounted on a purpose-built bracket that both
increased dissipation as well as fit nicely into the mount for the full-height
MFM drive ;-)
-ck
--
Chris Kennedy
chris(a)mainecoon.com
http://www.mainecoon.com
PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97