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Comspace CT-650

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    Comspace CT-650

    In my collection. 1 of only 3 known systems. With original dust cover and working. Sadly, not one of the ones made for the blind.
    Anyone who can give me an idea of value for insurance I would be appreciative.

    I was asked to evaluate one of these at the local high school, sometime around 1967. I don't recall the odd-shaped knobs, however--and the "program" sheets were various pastel colors and it seems to me, mylar or mylar-coated to keep wear down. The HS also had a Heathkit analog computer.

    I suspect that more than 3 are in existence--probably like contrabass sarrusophones--tucked away in some school district's storage.


      Had it on good authority.

      I was in touch with a professor of computer history when I first got this. He informed me that he has one and the family of the creator had one, but there was only rumour of one on the west coast. He nearly choked when I told him i had found one. Apparently only 12 were ever made. of which 2 or 3 were for the blind, having brighter lights so you could feel the temperature. I wouldn't be surprised if there were a few more lost as you say in basements somewhere.
      The program sheet on this one is paper. The knobs seem to be consistent with original images though. Perhaps in 67 you were evaluating a really early prototype.
      Still, would love to know what my insurance co will say. I doubt it is the most expensive system I have, but it is the rarest and fits so well with the period house we own.


        Certainly a very neat piece of history and system. Effectively aren't you able to set the price for your insurance? Are you associated with any of the collector hits that google pulls up? Very interesting read How to Build a Working Digital Computer (i.e building a small computing system from paperclips, light bulbs, and some wire)

        It's hard to evaluate prices on vintage, rare, or obscure equipment since it's sort of based on the last sales of the equipment which of course can be all over the place based on the timing and audience. I guess you've never heard of one being sold at auction? Alternatively try contacting one of the other folks who has one and maybe they've done some research or insurance bids as well?

        - John
        Looking to acquire: IBM 5100, Altair 8800


          I don't come up as a collector. I only have the images up on facebook. I have a digital copy of the book you mention, and want to get an actual copy to go with the system. I have never heard of one at auction save the one I bought. The professor I was in touch with said the same thing about it is worth as much as you can insure it for. The only research I found on line had it listed in a catalogue of vintage computer prices as "incalculable". which as cool as it is, isn't very helpful. I'm half tempted to put it on e-bay with a ridiculously high reserve just to see what the market will bear. Of if Sothebys does another tech auction it might go on the block.


            P.S. It runs Crysis...


              I can pinpoint the year pretty accurately, because I was introduced to the beast in the old high school and the new one didn't open until 1969. I'm sure it didn't have those funny-looking knobs and I don't recall the "Comspace" plated escutcheon. It might well have been 1968 or very early 1969.

              So it may indeed have been a prototype. As I recall, it was pretty boring. The Heathkit EC-1 analog was a lot more interesting. Did the bouncing-ball problem on it and still remember the click of the relay that started a new cycle. The EC-1 was purchased (assembled) at the same time as the CT-650, along with a Heath 'scope.

              A couple of years later, the school picked up a DG Nova--a "real" computer...


                lmao (Crysis). So you're gonna market it as a gaming rig? If you're wanting a physical copy of the book hunt around but I do see one or two on Amazon from various sellers (assuming they actually have the book and aren't just stealing hits).

                As far as value goes, you can obviously assume what you paid and convert that to todays dollar is your investment regardless (if you want).. I mean, really insurance is just the loss part so what are you wanting if it got trashed by a flood. say they have one in PA. Hm thought I found another person with one yesterday but maybe that was just the overpriced book and site referencing the document.

                I'd be curious about some of the pending patents actually Sellam used to do some appraising ( but I'm not sure if that's a source of income for him vs a friendly interest. There are a lot of early brain type systems on ebay and other early circuit trainer type of systems usually. They aren't always hugely profitable but are usually getting bids. The problem is the number of people looking at the auction who understand what it is and understand how they can use it/read the outputs.

                I thought about that even reading that book last night, if I ended up building a paperclip and light bulb machine with the thread spindles, etc would it be worth anything today or if someone found it would they mistakenly thing it's worth a lot? At that point it's probably a $35 novelty computer, of course yours is commercially built so it's better than just a random homebrew hack. Also if you want a lot of interest and price, show that it works (better yet that it works right heh).

                If you live close to any of the vintage computer fairs you could also bring it there as a great exhibit. To be honest I think it may be worthy of a museum (also another idea, then they can appraise or insure it sometimes if you loan it to them for display) although I think the end value from a sale might be disappointing to any of us. I'm no professional assessor though and the date of a system can certainly drive the value up.. on the bright side it does look like a computer which is appealing vs some of those electronic kits which look more like toys.
                Looking to acquire: IBM 5100, Altair 8800


                  The professor at Early computers was the one who I first spoke with about the system. I decided to call him up when I found so little information on line about this computer. He was teh one who told me that there were only 3 in existance that were confirmed... Well, two until I told him of mine. I believe the rumoured west coast one is the one I ended up with. I got it at an auction where the 'collector' and I use that term loosly, had about 50 sheds of 'junk' that went up for auction by his family when he died. They even aucioned a box of about 500 auction posters that he collected from the auctions he went to. So it would not surprise me if he did get this one at an auction on the west coast.
                  At some point Ill get a copy of the book, but I'm happy wit the digital version I have right now.

                  One book I would love to see again is one I had when I was really young. It was a Vic 20 book dealing with machine code and how to program your vic 20 using nothing but ".:34 56 29 83 73" etc. Used to have a great time going into Kmart and locking up their demo systems with that or with a simple print goto loop. then stand back solving rubics cubes and watch teh salesperson try to stip they screen from scrolling "Kmart sucks". Good Times... )

                  I was thinking about how much fun it would be to run Crysis on this... I could do up a program sheet with really cool drawings and depending on your input have different scenarios... could be a really freaky cross between the old DnD and Star Trek holodeck... or not.