Do you have any idea how much it would cost to ship a 400# machine? On Tuesday, February 25, 2003, at 02:26 PM, Peter C. Wallace wrote:

On Tue, 25 Feb 2003, Brian Chase wrote: Here's a better picture, and a page with more detailed information about the Monrobot XI and some other systems: <http://ed-thelen.org/comp-hist/BRL61-0672.jpg> <http://ed-thelen.org/comp-hist/BRL61-m.html#MONROBOT-XI> -brian.

All, Available as of right now, various DEC color monitors of the 19" and heavy kind. VR and VRT series. Obviously for pickup only, in the Hilversum-Amsterdam area in The Netherlands. What's left by next week will be scrapped - I need the space for machines. Cheers, Fred

on 2/25/03 4:57 PM, Brian Chase at vaxzilla(a)jarai.org wrote: Whoa. That is incredible. I would love to have one of those. It's beautiful. Bet it's a lot of fun to work with too. Probably fun to program something like that - 1K, paper tape, old printing typewriter console... -- Owen Robertson

I wonder how many other computers have had an article devoted to them in the New Yorker magazine: http://www.newyorker.com/archive/content/?010528fr_archive02 God! I'd love to go get one, but I literally have no space for one, wife or otherwise. I'll try to assist in a rescue if one is organized, I'm probably about an hour and a half drive away. Bill Sudbrink

On Wed, 26 Feb 2003, Vintage Computer Festival wrote: I would guess: Factor of ~1000 speed difference. I/O flexibility. The Monrobot would be too slow for lots of lab and process control applications that the PDP8 handles easily PCW

Sellam wrote: No, it suggests the question. "Begging the question" means making an argument depending on circular reasoning. The Skeptic's Dictionary is one of many web sites explaining this: http://skepdic.com/begging.html Because there were no other machines at the same time with similar atrributes at a similar price. However, many people consider the PDP-1 to be the first minicomputer, and it had even more improvement in price/performance ratio over its competitors than the PDP-8 had.

Sellam wrote: The PDP-8 does closer to a million calculations per second. I abhor getting English lessons on cctalk. :-)

On Wed, 26 Feb 2003, ben franchuk wrote: Ok, here is what I was referring to: "It can do an average of five thousand arithmetical computations per minute."

On Wed, 26 Feb 2003, John Allain wrote: That does make quite a difference, doesn't it? -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org * Old computing resources for business and academia at www.VintageTech.com *

Vintage Computer Festival wrote: Perhaps putting the cart before the horse, but I think the reason the -8 is considerd the first "minicomputer" is the sheer number sold. As has already been mentioned similar machines existed before with somehat similar performance or price points but the -8 realy caught on and that is what is remembered. Who can recall the story of the coining of the term "minicomputer"? Here in France we had a machine very similar to the Monrobot XI, it was called the CAB 500. Just the other day I was talking to someone who, for his PhD thesis project, interfaced that machine to a physics experiment. The CAB 500 was a drum based machine, and very interesting. It had a language called PAF which is extremely reminiscient of BASIC despite being some 5 years earlier. Unlike BASIC, PAF was designed so that its key words could be easily changed to different languages and on the fly during one progam, a feature I have not seen in any other language. For french reading members see : http://www.aconit.org/hbp/CAB500 we are continuing to develop that site as new information appears. -- hbp

The big part of the difference in speed between the PDP-8 and the Monrobot XI is that the PDP-8 used random-access magnetic core memory as the main memory and a parallel architecture, and the Monrobot machines used magnetic drum and a bit-serial architecture. In drum-based architectures, all operations, including instruction fetch, operand fetch, and (not sure with the Monrobot XI, but some machines did have all internal registers also located on the drum) register access had to wait for the drum to rotate to the proper location in order for the data to be read. In many cases, the master timing for the machine was generated by a dedicated pre-written clock track on the drum. Thus, the speed of the machine was limited by the rate of rotation of the drum and the density of the clock track. Along with all of the waiting time for the drum, the logic of the machines of this ilk was serial, which mated well with the fact that the data comes streaming off the drum in bit-serial form (in most cases). Serial logic is inexpensive...but slow (observe the performance differences between a PDP-8/L and a PDP-8/S). Another key difference between the early PDP computers and devices like the Monrobot machines is that the PDP was designed as a general-purpose computer, with expandability and a generalized I/O architecture to support a wide range of interfaces. Machines such as the Monrobot series were quite fixed in their architecture. There was no way to add more memory, or interface to more than a few external devices. The architecture was quite fixed. The Monrobot series of machines started out as early desk-sized sequence-controlled electronic calculators, with decimal arithmetic, and math-oriented functions. These machines were originally designed for automating accounting and bookkeeping operations. Some made their way into engineering and scientific persuits, though. The machines had little in the way of bit manipulation functions. As time and the marketplace went on, the Monroe machines (and others of the time, such as those made by Smith Corona Marchant (SCM), and Friden) began to take on more computer-like functionality...switching from decimal-based arithmetic to true binary, adding boolean logic functions, and providing more sophisticated branch and looping functionality...moving the machines from the realm of sequence-controlled calculators to true computer capabilities. Rick Bensene The Old Calculator Web Museum http://www.geocities.com/oldcalculators

On Fri, 28 Feb 2003, Rick Bensene wrote: <...> Great information! Thanks, Rick. -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org * Old computing resources for business and academia at www.VintageTech.com *