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Thread: The RICM Just Received a MITS Altair 8800 Donation

  1. #1
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    Default The RICM Just Received a MITS Altair 8800 Donation

    The Rhode Island Computer Museum just received a MITS Altair 8800 and ASR 33 Teletype as a donation.

    With some cleaning and fiddling it is now working. We plan to punch a 4k BASIC paper tape and see if we can load it using the Teletype. The long range plan is to program EEPROMs with BASIC and a loader to make it easier to demonstrate.
    Member of the Rhode Island Computer Museum
    http://www.ricomputermuseum.org

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    Oh dear, you have the 2x4KB DRAM boards. Horrible stuff; that's why MITS offered a special deal when you bought two of them with your system. Mine came with instructions to bridge the 7805 with a low-value resistor.

    Find some decent SRAM boards and save yourself a bunch of bother. Of course, if this is just a "for show" system, it doesn't matter.

  3. #3
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    Quote Originally Posted by Chuck(G) View Post
    Of course, if this is just a "for show" system, it doesn't matter.
    We plan to demonstrate the Altair with MITS 4k BASIC, so we will need working RAM.
    Member of the Rhode Island Computer Museum
    http://www.ricomputermuseum.org

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    There are many good 4K and 8K SRAM boards from the era! MITS' SRAM boards are usually OK, but many of the third party/other manufacturers' boards are better.

  5. #5

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    I use only CompuPro RAM boards in my vintage systems. I've found them to be ultra-reliable. Again, if it's an open-lid display, then maybe stick with the original, but otherwise go for what works better.

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    Quote Originally Posted by RichCini View Post
    I use only CompuPro RAM boards in my vintage systems. I've found them to be ultra-reliable. Again, if it's an open-lid display, then maybe stick with the original, but otherwise go for what works better.
    Yes, Godbout/CompuPro is some of the best you can get! Most boards that use 6116-type SRAMs are reliable, as well.

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    Yesterday we picked up the ASR-33 that goes with the Altair. it is missing the link that connects the keyboard assembly to the printer assembly, and the printer assembly is not attached to the base. Otherwise it looks complete and in good condition, so we should be able to fix it.
    Member of the Rhode Island Computer Museum
    http://www.ricomputermuseum.org

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    Quote Originally Posted by m_thompson View Post
    Yesterday we picked up the ASR-33 that goes with the Altair. it is missing the link that connects the keyboard assembly to the printer assembly, and the printer assembly is not attached to the base. Otherwise it looks complete and in good condition, so we should be able to fix it.
    I've got one that's also missing the little H-shaped plate that resets the keyboard after transmitting a key, keep meaning to draw up a pattern and make a replacement.

  9. #9
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    Quote Originally Posted by glitch View Post
    I've got one that's also missing the little H-shaped plate that resets the keyboard after transmitting a key, keep meaning to draw up a pattern and make a replacement.
    Try contacting some of the people on the Greenkeys forum. You might find someone who has the link.
    https://mailman.qth.net/mailman/listinfo/greenkeys
    Member of the Rhode Island Computer Museum
    http://www.ricomputermuseum.org

  10. #10

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    Quote Originally Posted by m_thompson View Post
    Yesterday we picked up the ASR-33 that goes with the Altair. it is missing the link that connects the keyboard assembly to the printer assembly, and the printer assembly is not attached to the base. Otherwise it looks complete and in good condition, so we should be able to fix it.
    I usually connect some switches to the distributor, in place of the keyboard, ( 8 pin dip works ), in local mode with some loop current, and manually run it through a cycle, locking the clutches as I go, being really slow by hand. Any really broken timing will show. It is not the same as running at speed but works to do a sanity check of the printer.
    You don't need to do all the characters, just change one bit at a time.
    Dwight

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