13 Aug
2013
13 Aug
'13
10:33 p.m.
Most (all?) IBM 360's have extensive margining controls on the front
panel. Customer Engineer intervention was regularly required on these
machines (more often than on your average server today), and varying
voltages was an effective way to turn an intermittent error into a
persistent one, which made tracing the fault to its cause a lot
simpler.
On Wed, Aug 14, 2013 at 2:53 AM, Chris Elmquist <chrise at pobox.com> wrote:
OK. Thanks for all the input on the topic guys.
It just struck me as interesting that they needed this adjustment on the
front panel of the machine-- which implied that they needed to adjust
it often.
I guess it was a long forgotten art of making the machine easily
servicable for their SEs :-)
Chris
On Tuesday (08/13/2013 at 02:33PM -0700), Don North wrote:
This is still routinely done even today on most high end equipment.
We have software control of all power supply set points, and
routinely margin the supplies +/-5% during diagnostic testing (as
well as stressing them from 0'C to 55'C ambient in thermal chambers
at the same time).
There are no twisty knobs on the front panel but the function is
there none the less.
Don
--
Chris Elmquist