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Gary Kaufman's IMSAI MPU-A Reproduction Board

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    Gary Kaufman's IMSAI MPU-A Reproduction Board

    Some of you have probably heard mumblings online about how someone's doing an IMSAI MPU-A reproduction. Behold:



    Gary Kaufman had a blank IMSAI MPU-A scanned and did a prototype run of boards. This is the same scanning technique that we've used on the OSI reproduction boards and my SSM IO-2 reproduction. I tweaked the Gerber files for him and added info regarding the design's status as a reproduction. Gary will be selling production-run blank boards soonish at around $30-40 per board depending on final costs. The boards will be run with hard gold edge plating (the prototype above is HASL, of course). I'll be building up a few parts kits for these boards.

    Intel 8216 bus buffers replaced with their Soviet clone counterpart:



    Running in my IMSAI:



    You can see garbage from the Polymorphic VTI on the little monitor; it hasn't been initialized yet. I dropped in a ROM board with the Vector Graphic ROM monitor with VTI drivers:



    It lives! Full album here: https://imgur.com/a/tAepr
    Check out The Glitch Works | My Retro Projects | Vintage Computer Services | Glitch Works Tindie Store -- Vintage Computer Kits and More

    #2
    Neat!!!
    Spread the joy of Vintage Addiction

    -->www.chronworks.com/<--->www.i8008.net/<--

    Comment


      #3
      Originally posted by 8008guy View Post
      Neat!!!
      Board are in production, and I'll offer them up in a few weeks.

      I also have Altair 8080 CPU boards being fabricated.

      Several folks including Glitch have been a huge help in making this possible.

      - Gary

      Comment


        #4
        There will be parts kits available for both, as well. Just got in an order of correct Thermalloy heat sinks!
        Check out The Glitch Works | My Retro Projects | Vintage Computer Services | Glitch Works Tindie Store -- Vintage Computer Kits and More

        Comment


          #5
          Originally posted by gekaufman View Post
          Board are in production, and I'll offer them up in a few weeks.

          I also have Altair 8080 CPU boards being fabricated.

          Several folks including Glitch have been a huge help in making this possible.

          - Gary
          Did you do a prototype run of the Altair CPU too? If so has Glitch and/or others tested a prototype of the Altair CPU?

          When orders are taken I'll commit to three (3) each of the Imsai and Altair CPU boards and parts kits for all.

          - Jeff
          ---
          KF7CRU @jhalbrecht @TheRetroWagon Looking for Solid State Music SB1 please DM me.
          http://www.theretrowagon.com/vcf-west-2017/

          Comment


            #6
            I did a prototype run of the Altair CPU as well. Here's a picture of a board built up by Martin Eberhard.

            - Gary
            Altair CPU Prototype ME_c.jpg

            Comment


              #7
              What are the prices for bare boards?
              Spread the joy of Vintage Addiction

              -->www.chronworks.com/<--->www.i8008.net/<--

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                #8
                Just waiting to figure my final costs, but will be in the $30 - $40 each range for bare boards. About 1/2 the cost will be going to cover the purchase/borrowing of the bare boards, scanning and prototype production/shipping.

                I should be ready to offer boards in about 2 weeks.

                - Gary

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                  #9
                  The Altair CPU board has been corrected from "CPU BB" to "CPU BD" in the final production Gerbers

                  Super excited to have reproduction boards actually *available* to us hobbyists at a fair price. I believe Gary is running them full-spec with hard gold plating and all, so they should also be very *durable* reproductions. Drives me nuts to see more expensive boards with HASL or ENIG on an edge connector!
                  Check out The Glitch Works | My Retro Projects | Vintage Computer Services | Glitch Works Tindie Store -- Vintage Computer Kits and More

                  Comment


                    #10
                    Originally posted by glitch View Post
                    The Altair CPU board has been corrected from "CPU BB" to "CPU BD" in the final production Gerbers
                    I thought that was on purpose because they are so close It is an excellent reproduction.
                    Maintainer of http://vintagecomputer.ca

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                      #11
                      I would be interested in one of each.

                      Len
                      Spread the joy of Vintage Addiction

                      -->www.chronworks.com/<--->www.i8008.net/<--

                      Comment


                        #12
                        Originally posted by snuci View Post
                        I thought that was on purpose because they are so close It is an excellent reproduction.
                        It says it's a reproduction on the back, with Gary's site's URL. They do look nearly identical to the originals from the front, especially the IMSAI board!
                        Check out The Glitch Works | My Retro Projects | Vintage Computer Services | Glitch Works Tindie Store -- Vintage Computer Kits and More

                        Comment


                          #13
                          Well done Gary. This is excellent.

                          I'd like to register my interest for 2 x kits (including 2 x PCBs), when available.

                          Are you able to post a few notes documenting the steps taken (tools used etc) to get from a scan of the old board, to a clean set of Gerbers and drill file? I recently finished an unrelated reproduction project. It took several hundred hours to accurately measure the placement of tracks and vias, while redrawing the lot in KiCAD. I'd say I did it in about the least efficient way possible!

                          Malcolm.

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                            #14
                            You send the boards to Mile High Test/Gardien Services, pay the fee, and get Gerbers back. They'll digitize all of the layers you'd like (silkscreen, solder mask, etc.). A two-layer S-100 sized board costs around $250. The board has to be stripped of all components. They can do multilayer (4+ layer) boards, but the board is destroyed in the process. Well worth the cost IMO -- as you discovered, there's a *lot* of time in it, and I wouldn't be able to get nearly as much done if I were doing the conversion to Gerbers myself.
                            Check out The Glitch Works | My Retro Projects | Vintage Computer Services | Glitch Works Tindie Store -- Vintage Computer Kits and More

                            Comment


                              #15
                              IMSAI and Altair CPU Boards are now available, please see the posting in the marketplace for-sale section.



                              http://www.vcfed.org/forum/forumdisp...-Sale-or-Trade

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