On Saturday 08 March 2008 18:35, Richard wrote: Yes, from a CDC 6x00 Pat -- Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/ The Computer Refuge --- http://computer-refuge.org

Richard wrote: An apocryphal story I heard was that the graphics on the display are disk/?drum refreshed. If true, I assume you would need the better part of a CDC 6x00 to get anything out of it. Jim.

The displays on the console were driven by a PPU (Peripheral Processing Unit), which were small scalar processors (actually, one processor multiplexed to appear as a number of independent CPUs), akin to small minicomputers (like a PDP-8), which operated out of shared sections of main memory. There was a PPU program that ran the display, generating it from data in a section of memory. The displays were vector only, not raster. There was dedicated hardware in the display console that did CDC character set (a 6-bit code) conversion to vector characters. Vector graphics were possible, within the limitations of the speed of the PPU. On later 6x00-series systems, such as the CYBER-73, the PPUs ran fast enough to generate a nice looking all-vector chessboard on the left screen, and a text-based transcript of the moves on the right screen. There were also a number of other cute programs, one being a pair of eyes (one on each screen) which would look around and blink. The operating system was called KRONOS, and I clearly remember that the console command to run the "eye" program was "X.EYES". Some privileged users could remotely fire off this EYES program from a terminal, and it'd make for a bit of a surprise, especially when we gave tours of the computer center to schoolchildren. I had the distinct privilege of being a systems operator on a Tektronix Cyber 73 (which was a derivative of the 6600) in the 1977-1979 timeframe (by which time the system was somewhat dated, but still incredibly powerful). It was an truly amazing machine. The machine had an array of toggle switches called the "Coldstart Panel" in one of the CPU bays into which a small (I think it was something like twelve twelve-bit words) PPU bootstrap program could be toggled in. The system could be booted from one of the "washing machine" drives, which was the usual mode of startup, or from magtape. There was a small pushbutton located just underneath the twin displays on the console, centered between the two screens that was the "coldstart" button that would trigger this boot program to be read by one of the PPU's, and boot up the system. At one time the drive with the bootpack on it failed catastrophically (headcrash, bigtime), and I had to once boot the system from magtape into a mini-OS that allowed the system to be mainbooted from an alternate drive with a backup bootpack mounted. Another interesting story relating to this type of console. There were huge power tubes in the console that made up the deflection amplifiers. I believe that these displays were electrostatically deflected. Anyway, I was sitting at the console at one time, doing the normal job of monitoring the various queues and CPU/PPU activity, and all of a sudden, the displays "compressed" into one thin, bright horizontal line. I reached for the brightness control, because I was afraid the line was so bright that it might burn the phosphor (which was a somewhat long-persistance phosphor to help minimize refresh "blink"), and all of the sudden, there was a loud POP and from an area just below the CRT's, (where the coldstart button was located), a shower of molten metal and sparks shot vigorously out of the console, right toward my face. Fortunately, the pop gave me a bit of a shock, and I reflexively pushed away from the console in my chair(which was on wheels), just quickly enough that I only got a couple of small balls of molten metal on my pant legs. The small balls of metal burned through the denim of the jeans, and made small burns on my legs. Through it all, the Cyber kept on running just fine. The fire suppression system detected the smoke from the failure, and went into alarm mode, which we cancelled (so the Halon wouldn't dump and the room powered down), and a breaker somewhere powered off the console. We monitored the system through a Tektronix 4023 terminal connected to a serial port on the one of the MODCOMP communications front-end machines, running a special program that allowed portions of what would be read on the displays to be seen on the raster scan terminal at a whopping 9600 baud. CDC came in and repaired the console (including replacement of some of those huge tubes), and we had the console back up and running within the same day. The Tektronix Cyber 73 machine had dual CPU's, something like 24 washing-machine sized multi-platter (I think that there were 8 to 10 platters in a pack), dual MODCOMP communications processors that did all of the serial I/O to interactive users on terminals all over the campus, a high-speed (standar IBM-compatible 80-column) punched card reader/punch, one 7-track magtape drive, and a couple of 9-track drives. It was maxed out on PPUs (I think it had 20), and maxed out on main memory (I believe, something like 256KW of 60-bit words), a high-speed chain-based line printer (1200LPM, IIRC). Lots of wonderful memories working at the Tektronix "Scientific Computer Center". Thanks for reading. Rick Bensene The Old Calculator Museum http://oldcalculatormuseum.com

Richard <legalize at xmission.com> writes: There certainly used to be companies that would rebuild dead CRTs for collectors of old TVs -- earlytelevision.org mentions Clinton Electronics, the sci.electronics.repair FAQ suggests Hawk-Eye Picture Tube Mfg, and curtpalme.com do it for projector CRTs. It's expensive, but it used to be a common process back in the 1960s, so the techniques are well-understood. If you've got non-working examples of the sort of tube you need, perhaps it might be possible to have them rebuilt rather than trying to replace them outright. -- Adam Sampson <ats at offog.org> <http://offog.org/>

On Sun, 09 Mar 2008 07:39:07 -0600 Tom Uban <uban at ubanproductions.com> wrote: This is a newer version of the Cyber console: http://static.cray-cyber.org/General/LARGE/Cyber_Big_Console.JPG It uses only one (still vector) tube to display the contents of the two tubes from the older console type. This console is connected to a machine that is run every saturday. Have a look at: http://www.cray-cyber.org/ You may contact Mr. Zabolitzky. IIRC he has full schematics for all of his systems. AFAIK he has one of the older two tube consoles in storage. -- tsch??, Jochen Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/

Hi Richard, Yes - CDC 6400 for this console. You can click "All Sizes" above the photo to see a larger image that shows the name-plate on top of the console. Hard to see on the original page. Cheers, Lee C. --- Richard <legalize at xmission.com> wrote: <http://www.flickr.com/photos/lee_courtney/2317092077/in/set-72157604065526114/> <http://www.xmission.com/~legalize/book/download/index.html>