Re; Revive 11/34

Noel Chiappa jnc at
Sat Dec 9 08:23:48 CST 2017

    > From: Henk Gooijen

A few comments to you about Henk's points:

    > Standing in front of the 11/34 processor box (looking at the console),
    > slot number 1 is at the right side.

That's for the 10-1/2" box; the 5-1/4" is different. Which is this?

    > Each slot has 6 positions. Position A is at the rear side, followed by
    > B thru F. Position F is thus at the front side.

I prefer to say that connector A is at the right, when facing the component
side of a hex-wide card which has the handles at the top, and the contact
fingers at the bottom.

(Make doubly sure you never plug a card in backwards! It will almost
certainly kill the card. In theory they are keyed so you can't, but idiots
like me have been known to do it! :-)

    > The 4 copper "jumper" traces should be facing the next higher-numbered
    > slot.

I.e. on the so-called 'solder' side of the card, not the 'component' side.
(All the cards face the same way.)

    > When you power up the system, the display should show 6 octal numbers.
    > If only one digit shows a number (7 or 5 or whatever), there is an
    > issue with the console itself, or the M7859.

The M7859's are, for some reason, particularly prone to failures. About half
the ones I've seen weren't working at first. There's no one chip that seems
to be the usual suspect, I've seen several different failure modes.

    > From: Jerry Weiss

And the same for Jerry...

    > It won't seat evenly if reversed. At least that is what my scraped
    > knuckles remember. 

Nope, they go in quite fine the wrong way around; I just checked.

Make sure they are in the right connector (D) and the right way around; I
haven't checked to see if damage is likely to result on an error - does
anyone know offhand?

    > Check the cable orientation. 

Note that one DEC manual (the KY11-LB Maintenance Manual) shows the wrong
orientation! See here:

at "Cable Connection and Documentation Error" for more.

    > I believe the cabling for the M7859 is a little different between the two

The /34 has two narrow 'maintainence' cables, the /04 only one. But you can
ignore these if you're not using the maintenance mode on the front console,
and only plug in the wide cable.


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