13 Aug
2013
13 Aug
'13
1:45 p.m.
I know on the SDS Sigma, margins were adjustable in a step up or down from
normal via a 3 position switch on the control panel/ This signal was
chained thru all the core memory power supplies. circa 1969 and before.
On Tue, Aug 13, 2013 at 11:06 AM, John Wilson <wilson at dbit.com> wrote:
On Tue, Aug 13, 2013 at 06:15:41AM -0500, Chris
Elmquist wrote:
Interesting pictures. I am curious why machines
of this era often have
a "VOLTAGE" adjustment on the front panel? Was it really neccessary
for an operator to adjust some voltage setting as the machine ran thus
requiring that adjustment to be easily accessible on the front panel?
I dimly remember (probably from the Gordon Bell book?) that KO+crowd
were weirdly obsessed (or maybe normally obsessed given the known failure
modes of the time) with marginal testing. So they liked to crank things
up to the high and low limits every so often to find parts that were about
to stop working at the nominal voltages. So I think that's what that is...
John Wilson
D Bit