Re: Cannibalizing 36xx's

[readingj@CERF.NET (John D. Reading)]

My experiences may not have a direct impact on Bruce's problems, but I thought
I could share what I have just been through.

We had acquired a 3600 from another division of our company, as well as a
3670 without a disk drive. Since I really wanted a 3670 instead of a 3600,
I proposed to remove all the useful parts from the 3600 and employ them to
get the 3670 running or keep them as spares.

The disk was the first target, of course. I found that when the disk had been 
removed from the 3670 they had taken the rails, too. I next discovered that
the rails from the 3600 do not fit in the 3670 cabinet. However, it is
possible to remove the bracketsd from the front of the 3600 rails, drill some
new holes, and reattach the brackets so that the rails are short enough to
fit. The rear brackets don't attach to the 3670 frame without some major
work, so I just turned them down and used them as feet. In retrospect I
should have drilled holes in the bottom of the 3670 case and tied down the
"feet", because now I have to be careful to support the disk drive if I pull
it out of the 3670 cabinet.

The electrical connections are compatible except for the power connection;
on the 3600 the disk drive plugs into a 3 prong plug, on the 3670 it is
screwed into a connector. The power connection is on the left hand
side of the 3670 cabinet (pop off the side panel to get to it). It helps if
you have another 3670 to look at.

All in all, it was a simpler job than I expected.

A couple of days later, the power supply (the one with the +/- 12 volts, 2
volts and 5 volt supplies) went out on another of my 3670's. That was when I
realized the power supply in the 3600 was compatible. Again, it is a very
simple job to swap those supplies. When I think of how much money I paid
Symbolics to replace that supply the last time it failed ... Whoops, 
flames about Symbolics maintenance belong in another thread.

Besides bragging to everybody about my abilities as a Symbolics repairman :-)
what I really wanted to share is that these repairs are not all that 
difficult if you are a little careful and think about what you are doing.
The consensus around here is "If Reading can do it, it must really be
trivial".

For what it's worth,

John Reading
readingj@cerf.net