19 Dec
2005
19 Dec
'05
6:08 p.m.
On 12/19/2005 at 12:46 PM William Donzelli wrote:
In the good old days, core planes were indeed repaired
by hand,
often during initial construction. Sometimes you can see the tiny splices.
At CDC, we used to joke about the "Tiajuana Core House"--at one time, bulk
core (ECS) was being assembled there, IIRC.
I remember an IBM CE poking around in a 7090 with a broomstick with a small
magnet attached to the end to retrieve fractured bits of core after he'd
given the unit a couple of good whacks to free them.
Core can be very fragile stuff, particularly when it's being heated by
repeated access. I recall that the CDC 7600 had some sort of duty-cycle
integrator installed on PP memory because repeated hits on the same
location would cause overheating and parity errors.
Cheers,
Chuck