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What are the top 10 rarest vintage computer bits you own?

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    #76
    Hi,

    1) Motorola MicroModule system
    2) Early Intel SDK85 with an 8085, as opposed to 8085A processor
    3) Early SDK86 with the black-top C8086 processor
    4) Central Data 2650
    5) Early IBM5150 with the expansion unit with twin full height 10Mb HDD
    6) SC/MP LCDS
    7) MicroProfessor MF-1P with printer, IO board and EPROM burner
    8 ) Intel MCS80 (SDK80?)
    9) IBM P70-D portable
    10) Intel IPDS

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      #77
      I thought of another one.
      NC4000 processor on a board. This was one of the early chips that Chuck Moore designed to run Forth more directly. Later variants of this chip design were on the early Mars rover. I recall that they had a 6MHz processor accelerator boards the were used to speed up 33MHz 386s, doing non-Forth application. Other than operations that had large literals or addresses, it could put 3 or 4 operations into a single instruction. It ran 3 16 bit busses at one time. It was fast.
      The board is on a home brew bus with a hacked XT floppy controller and a XT hard drive controller. The hard drive is one of the original 5Meg drives that I bought cheap at a yard sale. MS made them obsolete with its newer DOS that required 10Megs minimum. I recall, I payed $5 for it. I thought I'd made such a great deal. It seemed like just a few months that new hard disk dropped below $1 a meg.
      Dwight

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        #78
        Originally posted by Dwight Elvey View Post
        I thought of another one.
        NC4000 processor on a board. This was one of the early chips that Chuck Moore designed to run Forth more directly. Later variants of this chip design were on the early Mars rover. I recall that they had a 6MHz processor accelerator boards the were used to speed up 33MHz 386s, doing non-Forth application. Other than operations that had large literals or addresses, it could put 3 or 4 operations into a single instruction. It ran 3 16 bit busses at one time. It was fast.
        The board is on a home brew bus with a hacked XT floppy controller and a XT hard drive controller. The hard drive is one of the original 5Meg drives that I bought cheap at a yard sale. MS made them obsolete with its newer DOS that required 10Megs minimum. I recall, I payed $5 for it. I thought I'd made such a great deal. It seemed like just a few months that new hard disk dropped below $1 a meg.
        Dwight
        This is a highly desirable board. I’ve checked eBay for years and they never come up.

        You have a really interesting collection.

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          #79
          Once I understood how the NC4000 chip worked, I made a couple high level instructions with the low level code. Having 8 bit I/O, I needed a handy way to swap 8 bit values. I had a register at address -1, since that was an easy literal. It'd swap the 2 bytes. All done in two clock cycles. I thought that was an easy way to get bytes. The processor was so fast I had to put delays in to keep the floppy controller happy. It didn't have a chance to respond with the status otherwise. Using the hard drive, I could meta compile the entire Forth in less then 10 seconds. Not all that fast by todays standards but when one considers it was a 16 bit processor in 4K gates.
          Dwight

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            #80
            I mostly focus on NeXT black hardware. I have a few things I think qualify:

            Cube serial #57 with working magneto optical disk and NextStep 0.8 (Pretty much the pride of my collection). Lots of cool small details to this machine like a hand worked backplane.
            Engineering sample Next non-ADB keyboard
            A Turbo dimension NeXT cube

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              #81
              Originally posted by Dwight Elvey View Post
              Once I understood how the NC4000 chip worked, I made a couple high level instructions with the low level code. Having 8 bit I/O, I needed a handy way to swap 8 bit values. I had a register at address -1, since that was an easy literal. It'd swap the 2 bytes. All done in two clock cycles. I thought that was an easy way to get bytes. The processor was so fast I had to put delays in to keep the floppy controller happy. It didn't have a chance to respond with the status otherwise. Using the hard drive, I could meta compile the entire Forth in less then 10 seconds. Not all that fast by todays standards but when one considers it was a 16 bit processor in 4K gates.
              Dwight
              I've only read about it in Philip Coopman's book and remember that they used to advertise as 4 and 5 MIPs machines long before the 386 ever came out and the 286 was gasping to break 1 MIPS. It is a shame innovative architectures rarely take off.

              Occasionally Harris RTX (son of Novix) boards do show up in eBay, but they don't hold the same mystique.

              Comment


                #82
                Originally posted by Chuck(G) View Post
                How about rare items that you've had a part in developing?

                I've got all sorts of rare tidbits; a 1401 core frame, a few "cordwood" modules from a CDC 6600, etc. But the Durango F85 is special to me, as the the Poppy (which I have been fruitlessly looking for for at least 20 years). Narrowly missed one being junked in Australia a few years ago...
                What Chuck was a Poppy and if one was here in Australia could there be another ?

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                  #83
                  I don't keep anything around if it's both rare and worth a lot of money. I'd keep Voodoo5's around if they were as valuable as a RIVA TNT2. The money I make off a Voodoo card can go towards something useful, like expensive modern PC parts. Old computers are toys to me, but a Voodoo5 is cool looking nevertheless. I'm not a serious gamer. I don't mind low end cards like an Intel i740 or a TNT2 m64, they work well for the era of old games I tend to play.

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                    #84
                    I have some systems which might not be rare for others but they are for me because it took me a long time to get them.
                    My PDP8/E is an example and all the NOS modules which came with it.
                    Other items on the list are dedicated to Robotron, i.e. a "Kassettenlaufwerkseinheit K5261". A really nice cassette tape reader/writer.
                    I also like to add my variations of HP Apollo 9000/300,400 and 700 systems where the 300er is a complete set including screen, tablet and plotter.

                    And I have rare systems where I do not know how rare those are.
                    This NCR system is an example. So far I could just find a system close to but still didn't find a match. Maybe an early DMV prototype?
                    Ncr3 (Large).jpg

                    Some rare stuff is of pure industrial usage like a Balzer QDP-101

                    Most rare and the only one in the world is my PDP11 for VMEbus as it is self developed

                    Cheers,
                    Peter

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                      #85
                      I don't know if it's as rare as I've heard, but I have an Apple IIc Flat Panel Display in the original box. The box is pretty faded, but the display is nearly perfect. It was $15.00 at a second hand store in the 90's. I guess a deal like that is kind of rare.

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                        #86
                        I'd like to change my list a little.

                        Originally posted by snuci View Post
                        1. MCM/70
                        2. CPU Systems CPU-8 (Fairchild F
                        3. IBM 7690 Nursing station (PS/2 based)
                        4. IMSAI 8048 Control Computer
                        5. Bill-1 (8008 based)
                        6. Processor Technology Sol-PC
                        7. Zeus 80 (Z80 based)
                        8. Elenco Agvision (Tandy Videotex)
                        9. Tiger Learning Computer (Apple II based)
                        10. Viatron System 21
                        Maintainer of http://vintagecomputer.ca

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                          #87
                          The rarest pieces or machines would be those which there were only ever one of. So my first home computer was one I designed and built from scratch using TTL I.C.s and wire wrapping. That was the winter of 1975-76. It still works. Was programmed in machine language Hexadecimal format. Also designed and built a printer fro it. Still works too. Used it for running lab experiments for several years. 8 bit data with 16 bit addressing. 15 8 bit parallel ports for I/O which I sometimes connected a serial port module to.
                          Probably the rarest machine I have that was produced in numbers is my COM-TRAN TEN. That was a computer and electronic trainer back in the 70s, 80s and 90s. Its 8 bit data with 10 bit address bus. Thats where the 10 in the name comes from. Can therefore address a whopping 1024 bytes of memory. Was enough for training purposes. Mine is an early machine from 1972. Was used at Cincinnati Tech. The machine is TTL I.C. based. It is branded Fabri-Tek, later ones where Digiac. Early ones like mine have magnetic core memory. Later ones had solid state RAM. Still working on getting more of it working. Would really help if I had the schematics manual.

                          stephen

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                            #88
                            I think the rarest piece I own is a Motorola Atlas board with an IBM PowerPC which seems to predate their actual PPC line (PowerStack). Aside from my own sites, the only references online for this seem to be an old mail list thread and a copy of the manual if you dig deep enough. Most of the stuff I currently own isn't exactly rare but probably a little harder to find as they are higher demand such as the Mac Color Classic, Mac Quadra 840AV.
                            "Paul's Old Crap" retro computing videos

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                              #89
                              My rarest machine I own is a Tandy Model 16. Its in excellent cosmetic shape and I'm planning on doing a full restoration starting in January of next year.

                              Comment


                                #90
                                I don't have a huge collection yet(not enough to have a top ten rarest) but some interesting and rare electronics I own are:
                                A Newtek Calibar
                                A Commodore sx-64
                                An IBM PC 5150 (in excellent like new condition)
                                A Macintosh 512k
                                A functional PowerBook 100
                                Some weird card that I think was from the Altair 8800 (though it has proven to be untraceable).

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