12 Jun
2009
12 Jun
'09
6:37 a.m.
Ian King wrote:
we just got a restored PDP-8/TC08/TU56 booting OS/8!
Cool!
After calibrating the TC08, I turned off the system
to put all the 'skins' back in place, fired it up... and it wouldn't boot
After checking the obvious things, I decided to let the system warm up for fifteen minutes
or so. Yep, it booted fine.
Something tells me I need to look at the RC components in those one-shots and clock
circuits, and probably replace some realllllllllly old capacitors. -- Ian
I can't imagine that they would have used electrolytic capacitors in
those, and I don't think ceramics are likely to have gone bad unless
they've been subject to extreme mechanical shock. I'm not sure about
other kinds of capacitors, but I'd expect they'd most likely have used
ceramic.
I certainly wouldn't go replacing ceramic capacitors without using some
freeze spray to confirm that it is a temperature problem and identify
the failing component.
Eric