Forum Rules and Etiquette

Our mission ...

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
  • If you are starting a new thread choose a reasonable sub-forum to start your thread. (If you choose incorrectly don't worry, we can fix that.)
  • 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.
  • Do not bump threads.
  • Do not "necro-post" unless you are following up to a specific person on a specific thread. And even then, that person may have moved on. Just start a new thread for your related topic.
  • Use the Private Message system for posts that are targeted at a specific person.

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:
  • "PM Sent!": Do not tell the rest of us that you sent a PM ... the forum software will tell the other person that they have a PM waiting.
  • "How much is shipping to ....": This is a very specific and directed question that is not of interest to anybody else.

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
  • Use Google, books, or other definitive sources. There is a lot of information out there.
  • Don't make people guess at what you are trying to say; we are not mind readers. Be clear and concise.
  • Spelling and grammar are not rated, but they do make a post easier to read.
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Epson PX-8 repair: help needed!

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    Epson PX-8 repair: help needed!

    A week ago I picked up an Epson PX-8 through a local auction site. I had discovered the HX-20 before and I'm eager to learn more about these early Epson portables.

    The issue with this one is: it does not work.

    The basic voltages are there and I also found the clock signals which all seem to be present. Also, after a reset, switching on the machine using the main on/off switch actually brings up the 5V on the board. Switching off does not change the the state after that. The system ROM verifies ok.

    The LCD screen stays blank and the CAPS/NUM/INS leds don't blink or switch on (should they?). The LCD does respond to the view angle slide; it gets darker and lighter.

    The CAS and RAS signals on the PD4265 DRAM are there.

    The only useful documentation I found was a fair scan (PDF) of the Technical Manual.

    I'm looking for advice on next steps and also more resources for this machine. I found the F.J. Kraan site with a number of links, some working, some dead. Mainly looking for a good PDF of the operating system reference manual and any other resources.
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    Last edited by dutchacorn; October 10, 2021, 01:43 AM.

    I don't have a PX-8, but I do have an HX-20, which is just about working.

    Two things you might need to try to check.

    Firstly, the LCD unit might have failed. Totally. This has happened with the HX unit (not mine, luckily). This can arise if the unit has spend a lot of nime not being used, and not being changed.

    Associated with this fairly terminal problem, there may also be problems with certain elec caps connected with the LCD, if this is the problem then the repl of the caps can get things right.

    You say the contrast (view angle) control does something. Please detail. This should change from totally black to totally white, if that's the case then the LCD may be OK.

    Vintage Devices: Epson HX-20/TF-20, Amstrad PCW 8256 (with extras), 386 and 486 PCs with 5.25 and 3.5 floppy drives, Pentium 75 with Roland LAPC-I midi card


      Thanks for the suggestions, Geoff. If the issue would be the LCD I would expect the machine to do a startup beep? Or at least respond to the on/off switch. It seems not to get trough the start-up process and hang somewhere before a beep or screen output is generated.

      Here's what I mean with the view angle control:

      view angle high.jpgView angle low.jpg


        There usually is a startup beep and it looks like the contrast switch is working from your pictures. There seems like I remember a reset of some type on the underside when you open the plastic door. A few times I had my PX-8 in a state where it did not respond to the power switch, but pressing that reset helped.


          Yes, that’s the initial reset switch. If I switch on (5V kicks in), then slide the switch to off (no effect), then press the initial reset, then computer actually switches off. So the 7508 sub cpu seems operational.