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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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.
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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
  • 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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Bi-Tran Six

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    Originally posted by dlarue View Post
    valeen1959 thanks for the original post! The Bi-Tran Six was used by the USAF Air Training Command in the Instrumentation Mechanic (AFSC 317x0 [telemetry]) tech school at Lowry AFB Colorado, circa 1974. The training material and equipment were simple, but the instructors were top-notched. The computer lesson was brief, about 1 week of a 20-week course. At the time, most of the training was analog based. This short digital encounter with the Bi-Tran Six stood out and planted seeds for the future. A little while later a "personal training computer" was purchased, the $250 Kim-1. Off and running, a career was started based on the simple computer in your post. I sit here today, typing Python code with many powerful, graphical development tools, but there was nothing like learning the basics writing machine code, punching it in, and watching the lights flash! Please keep that baby running...
    To bad dlarue doesn't appear active I wonder if we might have met because I also trained as an Instrumentation Mechanic at Lowery in 1974 - in fact I still basically work the same job except as a contractor at Cape Canaveral for satellite telemetry systems. Some times I use to think the Bi-Tran 6 was something I made up since there appears to be very little data on it.
    Who let out the magic smoke!!!!!!!!!!!


      Here are some pictures of the COM-TRAN TEN


      The computer was stored in a barn for a long time and has needed a lot of cleaning. The third picture is of the core memory unit. The main display can be lifted on sliders for access to changing the light bulbs, raising the display for viewing and seeing the back side of the main circuit board. There are two views where you can see the main circuit board. Mostly TTL 7400 series I.C.s. I hope to get it working again. Give that about 50% chance at this point but that confidence is getting higher as I get into it more.


        Thank you for posting your pics! I have never seen one of these computers "in the flesh".
        How many bytes of memory is in the core module?

        EDIT: I think I found the answer to my question on page 45 of the CT-TEN Manual. 1024 words.
        (8 bit words - so 1KB)
        Last edited by livewire; September 24, 2017, 11:21 AM.
        where did the blinky-binkys go?


          Yes, the core memory is 1K bytes. The machine has a 10 bit address bus. The core memory is actually the part I have the most concern about getting working. So far the only part I have powered up is the front switch panel. Most of the lights and switches work. I did that test with all the ribbon cables disconnected from the main circuit board. No power on the main circuit board yet. I now have a replacement for the original power supply to continue testing. So far the display lamps appear to be ok but I haven't tested them all yet. That is 82 #47 6 volt lamps. Most of the power used by the machine is used to light the lamps of the display. Will be pulling each I.C. and cleaning the pins and replacing them one at a time. Will be testing some of the I.C.s when they are pulled.


            I would dearly love to run across one of those or even any further information on them.


              I studied Avionics when I was in the Navy. One of the schools I went to used a ComTran 10. I was shocked to see something so primitive being used to teach computer logic and progamming.


                Page 9 shows photos and a description of Fabri-Tek


                BI-TRAN SIX Computer Education System
                Fabri-Tek has recently introduced to the educational market
                the BI-TRAN SIX Computer Education System.
                The central unit of this system is a modern,
                inexpensive, general-purpose computer which is designed exclusively for teaching purposes.
                The BI-TRAN SIX system is used to teach the fundamentals of computer science at any grade level
                from secondary schools through college, and can be used in vocational and military schools as well.
                Complete course material for every grade level is available.
                Peripheral equipment, also designed specifically to teach, makes the BITRAN SIX system a complete instructional laboratory.


                  I used the bi tran six as part of a class in 1980. Then ran into it again in the air force. It was just for training on computer operation at a hardware level. You could trace signals for theory of operation. It was a base six machine. The lights on the front we're the actual registers if the cpu. All pre microprocessor.