Qbus Backplanes

From: Peter Turnbull <pete_at_dunnington.u-net.com>
Date: Thu Jun 5 16:43:07 2003

On Jun 5, 16:19, Tothwolf wrote:

> Since we are on the subject of VAXen...
>
> What would be the most likely problem with a BA123 MicroVAX II that
powers
> up, but sometimes totally locks up during the diagnostics? (I'm not
even
> sure it can boot, as some of the RD53s sound a little sick.) I've
pretty
> much eliminated the boards as the cause, and the only things left are
the
> backplane and power supply. It does have those older power supply to
> backplane wiring harness cables, which I guess I need to replace
before I
> put many boards in the card cage.

Could be voltage drop between PSU and backplane, resulting in low
voltage on the cards. Part of the problem with the harness (which was
discussed here some months ago, in a different context) is that parts
go high-resistance. Check the voltage (especially the +5V) on one of
the cards.

-- 
Pete						Peter Turnbull
						Network Manager
						University of York
Received on Thu Jun 05 2003 - 16:43:07 BST

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:36:07 BST