DEC H7260 PSU fault

Glen Slick glen.slick at
Sat Jan 27 16:13:06 CST 2018

On Sat, Jan 27, 2018 at 2:02 PM, Ethan Dicks via cctalk
<cctalk at> wrote:
> On Sat, Jan 27, 2018 at 4:34 PM, Jules Richardson via cctalk
> <cctalk at> wrote:
>> Success!
> Congratulations!
>> I'd left the rear panel console settings how they were when I got the
>> machine, I mean 'T' for terminal, right? Wrong... arrow for terminal, 'T'
>> for "sit there alternating between F and 9, and driving Jules insane" ;)
> 'T' is 'Loop Test'...

Page 37 of the PDF, page 2-6, Figure 2-2, CPU Patch Panel Insert.
Might be helpful to print out a copy of that figure and tape it to the
back of the BA123. I can never remember what the rotary and toggle
switch positions mean.

> Just be sure to follow the grant chain - the BA23 and BA123 have a
> hybrid backplane where the first few slots are CD slots and the rest
> are serpentine (3 CD slots for BA23, 5 CD slots for BA123).

First 4 slots of a BA123 are Q22/CD, not the first 5. Page 22 of the
PDF, page 1-11, Figure 1-9 Backplane Grant Continuity of the same
manual referenced above.

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