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Dr. Olds tells us about the time the Witch was destroyed by a burst water pipe

Wed Jan. 29, 1986 -- a very cold night.
About 1:20 a.m. the alarm box in the computer room called us at home. We were asleep & Betty answered the phone and did not understand the message and hung up. I knew what had happened and waited for the next call. When it called back, it said that the computer room was too hot, 91F. That was hard to believe on such a cold night. I thought it was nonsense, but before I could get dressed and leave, campus security called to say that a student working in the terminal room had reported water in the hallway, coming from the computer room next door.

When I arrived, I found the hallway flooded and the computer room badly flooded, hot, and saturated with steam. It was difficult to see more than a few feet. I picked up cables, electrical wires, paper and equipment from the water, shut down & unplugged the computers, etc. The DEC system had already failed. Brian Westcott and David Chinkes were working at the time & had heard the alarm box call my office after the computer went down.

Mike Caldwell and Paul Burrell (from Wofford maintenance) arrived & found that the hot water valve into the radiator had burst, probably from freezing. It may have frozen the night before, with a low of about 5F. In order to repair the valve, they had to drain the heating system of the entire building -- mostly, it seemed, draining into the computer room. [The radiator had burst about a week earlier & I had had to mop that up. It was then shut off on the input side but not the output side.. Computer rooms don't need heat, even in winter. The pipe was at an air intake below an outside window and the pipe had frozen and burst because no hot water was flowing in it.] Steam had condensed on and in the computer equipment and much of it was dripping wet.

Brian and David helped me put the water out the back door (where it then froze) and mop up. It was still coming in almost as fast as we could push it out. We tried to catch it in trash cans which were then almost too hot to carry out.

By 5:30, I had the floor pretty well dried and fans running in the computers and they seemed to be ready to test. The Microdata system could be rebooted and would run, although its printer would not run properly. We had dangerous ice on the back patio of Main Building. The DEC system would not start -- no lights on the front panel.

Shortly after 8:00 I called DEC & Microdata. Richard Drennan (Microdata service) came by about 8:30, then went after a printer kit. He replaced two boards & everthing seemed OK by about 9:30 or so. Pat Styles from DEC called ca. 9:30 but no one came until late in the day. Pat had never seen our system before & had not done much with an 11/40. However, he found voltage missing and began replacing voltage regulators. He said we probably would have to pay time and materials for this type of problem. I said we should be able to provide parts.

30 Jan. Thurs. I brought over regulators from an 11/40 we had in storage.

31 Jan. Fri. Pat got a late start & worked thru supper and later. During the day, I suggested he shorten the bus to isolate the problem. The DH11 appears to be bad among other things

1 Feb. Sat. Pat Styles & Leon Wood worked -- free -- in the afternoon. Leon seemed to know more about the 11/40 and which parts did what.

3 Feb. Mon. No one came until after 3 p.m. -- It was Chuck Richards & after some work, he suggested we give up on the 11/40 and install one of my 11/34s from storage. We began doing that by bringing an 11/34 from storage in Milliken Science Building. Chuck left shortly after 5 p.m. before much building of new system.

4 Feb.Tue. Chuck Richards finished up today -- rebuilding an 11/34 from parts I had -- more boards from storage and even an .RK711 controller. He installed an 11/34 box with front panel and:
M7265 and M7266, CPU boards
M8264 No Sack?? timeout
M7859 console interface
M9312, M7891, MR11-EA, MS11Ld Memory boards (4 by DEC, 1 by MDB)
[This was, I think, our new configuration, not necessarily all new parts]

The box is full. It has 5 DZ11s in it now, all current loop. My DZ11 from MDB is EIA, but appears to have water damage and need a repair. We did not use the DH which is probably bad.

5 Feb. 1986 Wed. It is up to me now to build the software. I can boot the RSTS disk, but need a new SYSGEN to properly recognize the terminals. I can't do a SYSGEN from my RSTS V8.0 distribution on tape. Never could. Also, could not run $CREATE.SAV on it. Borrowed V 8.0 tapes from Converse & could not read them. Did an on-line SYGEN at Converse and brought tape copies back -- but could not read them! Meanwhile, I created a SAVRES tape from the one on-line at ______[???} & restored to another disk. No information was lost! Anyway, I took this new pack over to Converse and copied the SIL I had created there (RSTSW.SIL). I also got copies of the files I might need for my own on-line SYSGEN.

For some reason, RSTSW did not have the options I requested -- only 25 jobmax and 7 Pseudo-keyboards. When I tried an on-line sysgen, it did not work because I did not have all the files I needed. During several trials, I gradually decreased what was needed. I was able to copy them with PIP from my distribution tape. Also, had several re-tries because I ran out of disk space. Finally, about 11:30 p.m. left a "final" system running. I had to kill out the old RSTS.SIL and SYSGEN.SIL but finally had room.

Chuck had set the addresses and vectors on the DZ11 boards wrong but CSR setting options allow software adjustments for them

6 Feb. Thurs. After class, I got the system running with some terminals up. The EIA and DH11 ports are not ready yet but I let the system run so students could finish Interim projects. Called MDB about EIA board. They will replace it.

7 Feb. Fri. Continue to run partial system. MDB said they do have a loaner board -- it should arrive Monday.

8 Feb. Sat. I worked all day on system. I moved all DZ panels to new rack & numbered the wires. I also removed all the DZ11 boards & reset the addresses and vectors as they should be -- dressed up the cabling and closed up the 11/34 box. Rerouted terminal wiring to new cabinet, cleaned, installed and tested the MDB board; at least some of it works. Installation of DZ cables is unclear. Chuck said there should be a half-twist in the cable. Not all boards were installed alike. I positioned the connectors at each DZ11 board so that cable is near board. At the other end (distribution panel) I tried to match the pins A & B to the marked side of cable. When I left, lines 2-18, formerly on the DZ11, were not working. Possibly a cabling problem & therefore fixable without shutdown. Need to do some more soldering on RS232 connectors that broke during moving.


Our computer room and terminal room were then in the lower center aisle of Main Building. I was pretty busy for a while, wonder how I had time to make all these notes. I felt a lot of responsibility to users who needed the system for academic work. You may be the only one who can understand the notes now. Are you planning to recreate this part too! Maybe make a movie? I would not recommend wading through water and picking up electrical cables! The Microdata system survived because it had a solid cover on top, with fans at the bottom rear. DEC had open fans on top which allowed water to drip in and be blown in, drowning the electronics. Somewhat before this time, Mr. Milliken had been replacing DEC computers in a lot of his plants. His castoffs were newer than what we were using and I was given lots of parts and systems.

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