• whew

    From Eli the Bearded@21:1/5 to All on Sun May 30 22:08:19 2021
    First a link:

    Vectrex commercial reproduced on a computer nostaglia account https://twitter.com/ComputerLove_/status/1371668449181757443

    Second:

    I bought a bought a capacitor replacement kit from Console5 and took
    mine apart then replaced all the caps. A little bit stressful working
    with that tube there. I know how to discharge a CRT, but I was still
    worried about bumping it. And then more stress with traces starting to
    pull off as I'm desoldering.

    I replaced them all, tested it, then finished reassembly with a lot
    of difficulty getting the back on (because the powerboard didn't have
    the exact angle to meet the notches in the back lid) and ...

    The display was messed up. Today I took it apart again and found a few
    suspect soldering spots, including one possibly broken trace. I
    resoldered two caps and added a jumper on that dubious trace.

    Tested, it worked again. Reassembled and it still works.

    Whew.

    Third:

    One of the reasons I choose to replace the caps is that I notice some
    games don't work. Most games I've tried play fine, but Star Trek, in particular, doesn't. The game starts up just fine, buttons work for
    selecting one/two player, and for selection game. But once the game
    starts, pressing any button jumps me back to game welcome screen. This
    happens with both an original cart and a multi-cart version.

    I've run the test cart, and other than the display being a little wider
    than it should be, everything seems fine. I figured it was some part of
    this game just pushing something a little far and cap refresh would do
    it. No, sadly. Ideas?

    Fourth:

    Oh, and while I was in there changing the caps, I took a length of heavy
    cable TV coaxial and liberated the braiding from it. I slipped that over
    the speaker wires and soldered it to a wire that connects to the same
    grounding connection that goes between the power board and the tube (the aquadag). Buzz is not gone, but definitely reduced.

    https://qaz.wtf/tmp/speaker-wire.jpg

    Elijah
    ------
    probably should have made the screen width adjustments while the lid was open

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  • From Computer Nerd Kev@21:1/5 to Eli the Bearded on Sun May 30 23:22:45 2021
    Eli the Bearded <*@eli.users.panix.com> wrote:

    I bought a bought a capacitor replacement kit from Console5 and took
    mine apart then replaced all the caps. A little bit stressful working
    with that tube there. I know how to discharge a CRT, but I was still
    worried about bumping it. And then more stress with traces starting to
    pull off as I'm desoldering.

    I know what you mean, I was in mine trying to poke probes at the
    VIA chip while the thing was running at one point - that was a bit
    nervous.

    One of the reasons I choose to replace the caps is that I notice some
    games don't work. Most games I've tried play fine, but Star Trek, in particular, doesn't. The game starts up just fine, buttons work for
    selecting one/two player, and for selection game. But once the game
    starts, pressing any button jumps me back to game welcome screen. This happens with both an original cart and a multi-cart version.

    I've run the test cart, and other than the display being a little wider
    than it should be, everything seems fine. I figured it was some part of
    this game just pushing something a little far and cap refresh would do
    it. No, sadly. Ideas?

    The cap replacement is mainly done to fix issues in the analogue
    stage (distorted display), whereas your problem would be with the
    digital circuitry. It sounds like an addressing issue, possibly as
    simple as a dirty or broken connection on the cartridge slot, but
    also possibly one of the 7400 series logic chips that do some extra
    address decoding on the logic board. I guess maybe the CPU itself
    could also be at fault, or one of its address outputs is shorting
    to another signal.

    I don't know anything specific about Star Trek to narrow down on
    which address lines would be most suspect, but it's obviously not
    jumping to the address that it thinks it's jumping to (in either
    cartridge ROM, or maybe the Vectrex ROM).

    Fourth:

    Oh, and while I was in there changing the caps, I took a length of heavy cable TV coaxial and liberated the braiding from it. I slipped that over
    the speaker wires and soldered it to a wire that connects to the same grounding connection that goes between the power board and the tube (the aquadag). Buzz is not gone, but definitely reduced.

    https://qaz.wtf/tmp/speaker-wire.jpg

    Nicely done.

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