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Thread: A SWTPC original TVT?

  1. #1
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    Default A SWTPC original TVT?

    This one's got me scratching my head. A user on reddit saw my post about my working TVT there and mentioned they had just picked up one from their late friend. Here's the photos:

    https://i.imgur.com/yD5diss.jpg

    The part that is confusing me is the PCBs. All of the SWTPC-manufactured TVT boards that I've seen to date have been the standard 70s green colour. These are blue! The mainboard is brown??

    I note too the corners used for alignment are not cut off. On every production board I've seen they are.

    I'm tempted to call these homebrew, but the presence of the silkscreening is throwing me off. Would a hobbyist etching their own boards have been able to do silkscreening like that?
    Last edited by falter; August 30th, 2018 at 04:01 PM.

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    Brown to me says a phenolic paper PCB body, not FR4, cheaper and less robust physically. On the other hand, a blue background for kit PCB silkscreen wasn't uncommon back then. I seem to recall that PAIA produced a lot of those.

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    Quote Originally Posted by Chuck(G) View Post
    Brown to me says a phenolic paper PCB body, not FR4, cheaper and less robust physically. On the other hand, a blue background for kit PCB silkscreen wasn't uncommon back then. I seem to recall that PAIA produced a lot of those.
    I know for sure SWTPC did produce some items on blue PCBs, like this KBD5:

    KBD5_Top_Photo320.jpg

    But this was years later. I've never seen brown from them.

    You know.. thinking about it know.. I seem to recall seeing on ebay either a TVTII or 6800 MPB board that was blue. But yeah, I thought this was a later practice.

  4. #4
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    I h\ave also seen blue on later boards. I think I have some in my late 6809 systems...
    Dave
    G4UGM

    Looking for Analog Computers, Drum Plotters, and Graphics Terminals

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    Yeah. I just didn't think they were doing the TVT kit much past 74. Maybe it was available later than we thought.

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    I think the TVT went well into 1976. One of the drivers was the availability of the MITS and IMSAI kits.

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    Quote Originally Posted by Chuck(G) View Post
    I think the TVT went well into 1976. One of the drivers was the availability of the MITS and IMSAI kits.
    Really? Seems strange they would keep the original design going that long. Especially since SWTPC had designed and was producing the TVT-II by 1975, which was a much better machine.

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    I misunderstood. Yes, of course the later revision would be the longer-lived one. The original always seemed like a terrible kludge to me.

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