[Info-vax] Assistance needed!! working RM05 drive and VAX needed for proje

[gah4]

On Friday, September 29, 2023 at 3:55:00 PM UTC-7, Rich Alderson wrote:

(snip)

> Glen forgets that most of the museum was devoted to small machines, since he is 
> a mainframer at heart. 
> 
> And the 4331 was a special case with respect to disk emulation (I forgot about 
> it, to be honest). 

(snip)

> > They had 3350's for the 4331, but never tried running them. 
> > There were stories about how hard they were to get running. 
 
> There shouldn't have been any stories about that--we never intended to try to 
> run them. See my earlier answer about learning our lesson WRT the Sigma. 
 
The stories were not from LCM, but from outside. 
It seems, for reasons I forget, that they are worse than others.

> > There are a lot of stories about the CDC 6500, not all of which I remember. 
> > When it was decomissioned, they cut the big cables that connect the 
> > different frames. So they had to rebuild those. They needed the pins 
> > for the connectors. (Since they had connectors, you do wonder why they 
> > had to cut the cables.) 
 
> > So they asked the company that made the silver plated pins about 
> > buying more. The company said that there was a minimum order. 
> > (I don't remember the number, but it might be 1000.) LCM said yes. 
 
> > Then the company said that they didn't have that many! 
> > They still got a lot more than needed, though. As far as I 
> > remember the story, the budget for that one was $1 million. 
 
> You've remembered almost everything exactly wrong. 
 
It was some years by now.

I think, though, that I am remembering the explanation given
to tour groups, which didn't have quite as much detail as:

> When the School of Engineering at Purdue was finished with the 6500, in 1989, 
> CDC decommissioned it in order to donate it to the Chippewa Falls Museum of 
> Industry and Technology, in Seymour Cray's home town. (The local industry as 
> the Leinenkugel brewery, the technology was Seymour.) It was CDC who cut all 
> the interior cables off at the bulkheads. 
 
But why cut the cables, when they could unplug them?

Reminds me, though, for the 360/20 someone did nicely remove the
cables, and then the museum didn't get them.  Might have gone to
metal recycling.  There are nice cable clamps that someone screwed back
together after removing them.

And even with cut cables, one could (hopefully) match up the colors.

> The company which built the original cables is (was) still in business, and 
> even had the original build specs from when CDC ordered them: 19 coaxes in a 
> bundle, specs on frequency response and all that. 
 
> Back in the early 1960s, when Seymour designed the 6600 and its follow-ons, he 
> did not like either gold or tin for pins. He specified silver. NB: Not 
> "silver plated", solid silver. 
 
> We needed about 10,000 pins for the new cables. The company which made the 
> pins could do it, but their minimum order was much larger; we had to provide 
> enough silver bullion to make 50,000 pins. 
 
Cray was always hard to figure out. He liked ones' complement for the CDC
machines, though finally two's complement for the Cray-1.

But there was some story, which I forget the details of, that there was a 
minimum order, and then they didn't want to make that many.

But I don't remember either of the numbers.

> The pins are easiy bent, so we probably used 12K-13K putting the system back 
> together. The late David Cameron nearly went blind (and crazy) getting all 
> those pins inserted; in the end, we found only two or three that he got wrong. 

I don't think tours got this explanation.

> [ snip ]
> > Reminds me of another DEC disk, which can be used on either PDP-10 or 
> > byte addressed machines. The controllers are different, and can only write 
> > blocks with the appropriate size, which I believe is 576 bytes for the PDP-10, 
> > and 512 otherwise. You can't read disk packs on the other one.

> That would be any RP06, RP07, RA81, RA60, or RM03.
 
So not just a switch or jumper, but needs a whole new controller.