seeking advice on moving PDP 11 and related gear

tony duell ard at
Sat Jul 4 09:51:14 CDT 2015

> In a day when digital cameras are available, always take lots of pictures.

Although undoubtedly useful, photographs (digital or otherwise) are not IMHO
a replacement for making notes. It s still a good idea to document where
cables go and which way round (this may not be obvious in the photo), any 
non-obvious mouting hardware (special washers, locknuts, ettc) and so

Oh, and make sure you know how to take a decent close-up with your camera.
Based on the out-of-focus things which seem to consist mostly of flare from the
flash unit which people asking for help expect me to be able to understand, being
able to take good close-ups is by no means a universal skill

IMHO do not use flash unless you really have to. Keep the camera as steady
as you can (brace it or yourself against the rack). And if there is a closeup
setting (often a picture of a plant/flower) use it.

I find tie-on card lables to be very useful for labelling cables.

> Even short videos with voice description is a good idea.
> Bring snack baggies with a sharpie pen to put notes as to where
> to put the pieces back, for small parts.

I normally take a couple of those 'organiser boxes' with lots of small compartments
and put the screws, etc, in that. And drop in a slip of paper if it's not obvious what 
something is. I do the same on my workbench when dismantling a complex unit, so the 
boxes are not 'wasted' they get used almost all the time. As a practical point, get ones with
fixed partitions, not removeable. The latter look convenient, and are often recomended by
reviewers, but my bitter experience is that the partitions fall out when you least need them to
and everything gets mixed up.

Never leave screws loose. If you just have to loosen screws (e.g. the top cover of the 11/34 CPU
then either put the cover back and tighten the screws or just tighten the screws in their bushes. 
Loose screws invariably get looser, fall out, and get lost (or worse find their way into a PSU or 

DEC used this clip-on nuts to take the screws in the uprights of their racks. Without a#screw
in them they get knocked off or out of position very easily. If you do unscrew anything from
them, then either unclip the nuts (but note where they go) or put the screws back in _and
tighten them_. 

If it's a real DEC rack there will be header panels at the top. These are quite delicate and
on any case will obstruct the screws holding 2 racks together. Take them off (2 screws from
the top and pack them separately. As above, either remove the clip-on nuts or put the screws
back in.

> Of course, do the minimum necessary to removing pieces. Worry

YMMV, but I diagree there. It depends on what it is, the vehicle you have
and how many friends you have helping, but I suspect a loose rack
unit (CPU, drive, etc) is a lot easier to handle carefully than a complete

Another use for cable ties (take plenty!) is bundling up cables and fixing them to the
rack. Some cables can be removed easily, but things like the mains cable often
can't. And you don't want it trailing around where you _will_ end up tripping
over it.


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