Forum Rules and Etiquette

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This forum is part of our mission to promote the preservation of vintage computers through education and outreach. (In real life we also run events and have a museum.) We encourage you to join us, participate, share your knowledge, and enjoy.

This forum has been around in this format for over 15 years. These rules and guidelines help us maintain a healthy and active community, and we moderate the forum to keep things on track. Please familiarize yourself with these rules and guidelines.

Rule 1: Remain civil and respectful

There are several hundred people who actively participate here. People come from all different backgrounds and will have different ways of seeing things. You will not agree with everything you read here. Back-and-forth discussions are fine but do not cross the line into rude or disrespectful behavior.

Conduct yourself as you would at any other place where people come together in person to discuss their hobby. If you wouldn't say something to somebody in person, then you probably should not be writing it here.

This should be obvious but, just in case: profanity, threats, slurs against any group (sexual, racial, gender, etc.) will not be tolerated.

Rule 2: Stay close to the original topic being discussed
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  • If you are responding to a thread, stay on topic - the original poster was trying to achieve something. You can always start a new thread instead of potentially "hijacking" an existing thread.

Rule 3: Contribute something meaningful

To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
  • This is not a chat room. If you are taking less than 30 seconds to make a post then you are probably doing something wrong. A post should be on topic, clear, and contribute something meaningful to the discussion. If people read your posts and feel that their time as been wasted, they will stop reading your posts. Worse yet, they will stop visiting and we'll lose their experience and contributions.
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Rule 4: "PM Sent!" messages (or, how to use the Private Message system)

This forum has a private message feature that we want people to use for messages that are not of general interest to other members.

In short, if you are going to reply to a thread and that reply is targeted to a specific individual and not of interest to anybody else (either now or in the future) then send a private message instead.

Here are some obvious examples of when you should not reply to a thread and use the PM system instead:
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Why do we have this policy? Sending a "PM Sent!" type message basically wastes everybody else's time by making them having to scroll past a post in a thread that looks to be updated, when the update is not meaningful. And the person you are sending the PM to will be notified by the forum software that they have a message waiting for them. Look up at the top near the right edge where it says 'Notifications' ... if you have a PM waiting, it will tell you there.

Rule 5: Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

Our discussions here generally fall under "fair use." Telling people how to pirate a software title is an example of something that is not allowable here.

Reporting problematic posts

If you see spam, a wildly off-topic post, or something abusive or illegal please report the thread by clicking on the "Report Post" icon. (It looks like an exclamation point in a triangle and it is available under every post.) This send a notification to all of the moderators, so somebody will see it and deal with it.

If you are unsure you may consider sending a private message to a moderator instead.

New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.

Other suggestions
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Busted Micro Switch keyboard -- need help with PCB

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    Busted Micro Switch keyboard -- need help with PCB

    So I got this parallel ASCII keyboard with a couple S-100 boards at a garage sale (this is why it's in the S-100 section), but the problem, as you can see, is the busted PCB. Seriously, did someone take a machete to this thing?
    Model number on the board is "SDR SD-16396"
    Anyway, there's a chunk, completely missing from the side. I can't repair the traces; because there are no traces. Does anyone have images or schematics of the PCB of an intact version, which I can replicate with bodge-wires?

    EDIT: first uploaded pictures didn't work. Trying again.
    Worked that time : )
    Current favorites: IBM 5160 (EGA+Hercules+PGC, 8 floppy drives, XT-IDE), DCC D-116 (Nova 1200 clone), ASR 33 Teletype, PDP-8/I (lots of issues, restoration underway)
    Wishlist: IBM 5161 (expansion chassis), Diablo 31/RK02/RK05 or equivalent, Data General equipment, and the meaning of life.

    what a horrible thing to do. they took a hacksaw to the control and keypad sides of the pcb, taking a chunk of one of the matrix decoding ICs with it
    with a lot of tracing you should be able to reconstruct the x/y matrix layout of the full keyboard, but by then you would be better off just unsoldering
    all of the switches and resusing the switches and keycaps on a new pcb, since you are missing all of the keycaps on the left and right sides.

    I would only consider doing all of this work because microswitch kbds are very high quality and you have at least a dozen spare keyswitches on either


      Yeah, if I can find another PCB layout for a parallel keyboard that uses the same chips (or things I have on hand), making my own PCB with the original switches is definitely an option. Though I'd much rather have it in the original hardware, with that metal plate thing that holds all the switches in, if I can manage to repair the traces.
      Also, that chip is actually intact, by the skin of its teeth. There's like one pin that's just hanging over the side. I did meet the previous (and original) owner, and I got the feeling that it was broken out of negligence, rather than ignorance or malice. Still, the deed is done.
      Current favorites: IBM 5160 (EGA+Hercules+PGC, 8 floppy drives, XT-IDE), DCC D-116 (Nova 1200 clone), ASR 33 Teletype, PDP-8/I (lots of issues, restoration underway)
      Wishlist: IBM 5161 (expansion chassis), Diablo 31/RK02/RK05 or equivalent, Data General equipment, and the meaning of life.


        Look at the vandalism done on Model M keyboards (e.g. Is it really indestructible?).

        I'm with Al on this one--scavenge the switches and use a new PCB. Thanks to modern technology, a keyboard decoder is easy with a microcontroller.
        Reach me: vcfblackhole _at_ protonmail dot com.