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    Possible Philco Transac 2000 board

    Thanks for the great information! Too bad it doesn't say what computers it worked in. At least I have a great place to start.
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    Possible Philco Transac 2000 board

    This is an interesting early board that looks like it has the same output format as a couple of other Transac 2000 boards I have found on-line. The contacts are only on one side of the board. Is anyone familiar with any other computers that used this same format?
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    TV Typewriter Keyboard like Don Lancaster prototype from SWTPC

    Here are a couple of shots from the back. I did find this on Brad's Blog where he talked to Don Lancaster, "When I asked him about it, his response was that the keyboard was an ‘IBM EBCDIC’ surplus unit. They had taken apart dozens of them and reconfigured into just over 40 complete units that...
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    TV Typewriter Keyboard like Don Lancaster prototype from SWTPC

    I'm guessing the keys were chosen and placed based on their color. There are also 2 B and P keys. I believe these were made from surplused keyboards.
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    TV Typewriter Keyboard like Don Lancaster prototype from SWTPC

    I am posting this mostly because I think it is very interesting and worth a discussion. The only question I have is, have any other people heard of these being available? The mailing date is Sep 18, 73, which would coincide with the article by Don Lancaster in Radio Electronics magazine. I'm...
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    Unusual Transistor Computer card

    Looks like they plug into this. Copied from DDP-24 https://www.p3oriontopsecret.com/3c-computer-control-company-ddp-24-card-rack.html
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    Unusual Transistor Computer card

    One last follow-up on this. After interpreting the company codes in the JPL document, it looks like the breadboard is a magnetic logic board using RCA transfluxors for a 3C Computer Control Company DDP-24 computer. Thanks to everyone for the invaluable input! DDP-24...
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    Unusual Transistor Computer card

    Here is an excerpt from another JPL article from 1965. There are several more diagrams with logic functions using the 2N2297 transistors.
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    BYTE, Inc. Backplane Motherboard C61102

    Thanks for the info! I have read the articles on deramp and wiki before, but apparently didn't keep it in long term storage. I'll look and see if I have any more documentation or kit parts. Seems like a cool computer kit.
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    Unusual Transistor Computer card

    Thanks to all for the great information. I have been researching early ICs (DTL, RTL and TTL) in the JPL data archives. One of the documents I found is called "Circuits and circuit testing for spaceborne redundant digital systems Special technical report no. 3" It covers research in comparing...
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    Unusual Transistor Computer card

    So, to add to the intrigue, this is likely a card used by the JPL (Jet Propulsion Lab) in Pasadena, California (predecessor of NASA and now part of NASA). I have a number of oddities that I am trying to wrap my head around. I'll probably post more boards and cordwood units. I think many were...
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    Unusual Transistor Computer card

    Does anyone recognize this card? It has unusual gold plated connectors that look more like forked posts. I do think this is a DIY board. The transistors are Fairchild 2N2297 and Motorola 2N2219 from the mid 1960s
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    BYTE, Inc. Backplane Motherboard C61102

    Does anyone have any info on this motherboard? It appears to be an S100 with 10 bus ports. Obviously, it originally came in kit form. I've looked through the first 15 or so BYTE magazines and cannot find a reference to it. I'm not positive it is even related to the magazine. I'm trying to find...
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    Anyone recognize this Apple ][ clone motherboard?

    I'll try to take some better, more uniform pictures of the motherboard so all the components can be read and pieced together.
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    Anyone recognize this Apple ][ clone motherboard?

    Sorry, I do not have an EPROM reader for a working system. Here are some additional pictures of some of the chips that are hard to read in the other pictures. This board comes from a person with a ton of vintage computer hardware and he wasn't sure about where this one was from. It was with a...
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    Anyone recognize this Apple ][ clone motherboard?

    Sorry for the delay. I've had some surprise issues to deal with this week. I'll try to get some better pictures and some pics of the back. I can try to trace the IC back to the power connection as well.
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    Anyone recognize this Apple ][ clone motherboard?

    Does anyone recognize this motherboard? It appears to be an early Apple ][ clone. Maybe a homebrew version. I don't know. No system bus on the motherboard.
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    RAM Chips on OSI 420 memory board

    I did find the logo is for Intersil. I also found the invoice in some paperwork. It is invoiced as 32 Intel P2102AL ($1.75 each).
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    RAM Chips on OSI 420 memory board

    I am trying to figure out more about these. The documentation says 2102 RAM and I'm sure this is a version, but I can't find other examples labeled this way. It looks like an Intel but I don't recognize the lower case I in a black box. Any help would be appreciated. White chip with gold...
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    Xitan Alpha computer with ZPU board, SMB and 2 16k memory cards

    I am planning to get this into working order. I haven't tried powering it on yet because of the power supply capacitors. I have not been able to get a good idea of the value because of its relative scarcity. Anyone have a ballpark on what these are currently worth? I think I have most of the...
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