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Bi-Tran Six

Bi-tran Six, Used one in 1970-71 10th grade computer science class. I think it could do math with a result up to 31. I remember something about a bit being used to designate negative number. And some functions like greater-than and/or equal-to. My teacher used it to demontrate programing in machine language. I remember the pull out core memory boards and it was on a rolling platform. Pretty big for what it's capable of. Wow, that's a long time back.
 
In high schoo,l circa 1970, we had one of these we used to learn programming. It had registers you loaded with binary data and program instructions, also in binary.
The switches on the bottom were to increment or decrement to the next instruction. You would enter the binary data by turning on the lights on the front panel
then click the switch to enter the instruction/data. Other panel lights would show the contents of the registers and program memory. At 16 it was fun to play with and was
my first introduction to programming.
 
When I was in the Navy, going through electronics school (one of them, I can't remember which) in Millington, Tennessee, somewhere between September 1977 and September 1978, we were taught about computers using a computer trainer called the "ComTran-10", or something like that.

I don't remember much about it, except we programmed it in machine code. Has anyone heard of it?

Dr. Pepper,

I also used the ComTran-10 in Computer School, Keesler AFB, MS back in 1979-80. I remember the hex code for Manual Input, it was F0, that sticks in my mind because our instructor told us that "now if anyone asks you if you know what F-O means, you can tell them 'yes, it means Manual Input'"

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

Art
 
The first time I came across the Bi-tran six was in 79 at Community college. We had to purchase the maintenance manual for the course. Unfortunately I lost it in a move in 04. The Air Force tech school at lowery AFB used the Bi-tran six for some basic computer training.
I remember it being a base six number system and designed to teach CPU workings. All the registers were displayed on on the front with switchable lights. All the circuit boards could be extended from the top and measured test points during operation. It was very basic coding. one of the routines we coded was multiplying two numbers. The instruction set could only add two numbers. Even at that time microprocessors had a multiplication instruction.
The Bi-tran six was a real good tool for teaching how a CPU works that's about it.
 
i found a picture of it thats prety cool looking, im amazed it is working
 
I learned about computers in the Army in 1974 on a Com-Tran Ten. I was digging though some old stuff and found a couple of manuals for it. I had to check online to see if anyone else remembered it. Apparently I'm not the only old guy online :)
 
Bi Tran Six

Bi Tran Six

Looks like this thread will never end...................

I was introduced to the bi tran six back in 1967 while in the Navy at Polaris Electronics "A" school at Dam Neck Va. I recall being dazzled by the lights and the ability to program a machine to do calculations - really neat at the time.
 
I encountered a Bi-Tran Six as a student at the Temple University Technical Institute in Philadelphia in the fall semester, 1967. It was the first computer I ever programed, and the lessons lasted an entire career.

The B-Tran had a very limited amount of core memory, and the memory was organized into words of I think eight bits (implying a very small addressing range). You would program the computer in machine language, meaning that you would write out your program as a series of zeroes and ones then enter the program by pushing the associated buttons, into memory. The Bi-Trans had a few registers, most notable the accumulator upon which the instruction set operated. We students could step through the program, which would present the state of the machine after each instruction.

I was fortunate to get such a fundamental education understanding the Bi-Tran Six.
 
I trained on the Bi-Tran Six during Polaris Electronics "A" school at the US Navy Guided Missiles School in Dam Neck, VA, in late 1968. I don't have the reference readily available, but I think I read somewhere not that long ago that it only had 1.9 kilobits (not even bytes) of memory. I had played with some Tandy electronics kits (radios and the like) during my high-school years, and this computer didn't seem highly complicated, though from the front it did look somewhat like it came from the movie Forbidden Planet (introducing Robby the Robot) where the daughter was named Altaira (pretty close to Altair). Later operational computers and testing consoles looked like they were right out of the Sci-Fi movies of that era. It was an amazing time, and I wouldn't have missed it for the world.
 
It turns out the Bi-Tran Six was built by Fabri-Tek. It had 128 6-bit words worth of memory, which is only 768 bits, or 96 bytes, if my math is right. There were only about 30 commands available, too. I seem to recall being able to actually see the memory devices, which were made up of small, metallic rings with crossed wires going through them, one wire to write and the other to erase the bit by reversing the direction of the magnetic flux in the rings, with perhaps a third wire to read the flux direction. Alternatively, maybe current in one direction and then the other set or unset the bit, and only a second wire was required for reading the bit. Perhaps the years have clouded my own memory, but that's what comes to mind about those early days of study (often on the graveyard shift, in class all night and sleeping in the heat and light of day, without air conditioning, in the shack near the base we rented to get out of the barracks). The shack was located on a pig farm in the swamp and should never have been cleared for human habitation. Ah, the good ol' days!
 
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Hi Yes I was a Navy instructor that taught the 6 at Polarsis "A" school in Va. John the submariner mentioned the name of the manufacture Fabri-tec I believe. The U S Naval Acadamy had one also and if I know them they probablly still have a copy of the manual and teaching guides in their achives. You may want to try them. Also you could try the Guided Missile School at dam Neck Va and see if they have a copy in their achives. If you would like to get rid of it I would love to have it to show my sons and grandchildren the inner workings of a computer and especially core memory principals. Machine language was the big thing back then , Grace Hopper hadn't done to much on cobalt language programming except in the gov't. She was the first woman admiral in the USN. Oh, well I'm rebbling on. thank you for the memory (PUN)
 
Hi John: Did I teach you the 6 or did you have another instructor. Joe MullerMT1(SS). later chief
 
I haven't seen a Bi-Tran 6 since Dam Neck. I did look it up on the Web and talk about it to some of my classes. When I describe the total memory, they are incredulous. When I describe the core memory, their eyes glaze over. I wish I had a good memory for names but, alas, that is not the case. I sometimes have to check my own ID before I introduce myself. I have a knack for remembering faces. I saw a guy on a ship in Japan back in the early 90s and just knew I knew him. It turns out he was an MT2 on my submarine back in the late 60s. He was always the biggest complainer and detested "lifers." He couldn't wait to get out. Lo and behold, when I met him 22 years later, he was a tech rep and had been the COB on subs by the time he'd retired. It's truly a small world. I arrived in Dam Neck around September of 68. It seems like PE "A" school lasted until just after Christmas, and then MT "C" school lasted until early/mid summer. Some of the class went into the relatively new C-3 training, some went to A-3 training, and I went to A-2 training. I recall some of the machinery we trained on. The Bi-Tran 6 was dazzling to me. I also recall a MTRE trainer that ran off of paper tape that was my first exposure to stored-program computers. I do recall the CPO instructor on that machine who chewed me a new one when I hit the reset button after none of us could figure out what the displayed code output represented. He was a pipe smoker. I also remember some fellow students taking diet pills. They were already thin, so I couldn't figure out why they would be worried about their diets. I was too naive to understand that they were basically taking uppers to be alert in class. I loved to run on the beach, especially the gunnery range portion when they weren't firing, as it was usually pretty deserted. Boone's Farm strawberry wine was popular among students those days. Also, beer. If I recall, we could drink "near beer" either there or in Groton. The barracks were no Taj Mahal for someone who was a light sleeper. I recall spending hours using towels to "snap" wasps out of the air in our spare time. They were everywhere, as the windows were always open to catch a little breeze. The noise in those "cubicles" was usually deafening. The dividers were little more than a few of those partial panels they put in heads. It wasn't much of a step up from boot camp (Great Lakes). Two buddies and I moved off base at our earliest opportunity in the spring. Late spring/early summer in the swamps of Dam Neck, living in an old pig shed that a farmer had converted into a rental for guys just like us, low ceilings, three rooms, the size of a small travel trailer overall, no air conditioning, and the graveyard shift at USNGMS so they could pump through students as quickly as possible--you can't buy an experience like that. We'd lie on top of the sheets in just our skivvie shorts during the day, sweating profusely, with a table fan running, blankets over the windows, trying to get a few hours of shuteye before going back to school late. Ah, memories. After C school, I was put in charge of an X Division for almost a month, if I recall. It wasn't just guys like me awaiting orders. The guys who'd been kicked out were also put into the division--cleaning heads. As a brand-new E-4 technician trying out his untested leadership skills for the first time--with sailors over whom I had no real power, i.e., what was I going to do to someone who was already on the way down or out of the service?--it was another eye opener. My orders to the George Washington worried me. I had heard so many bad things about that first boomer. The underwater-escape/free-ascent tower trainer in Groton had a fire, so I didn't get to do that. We ended up pretending in the nearby lake (Rock Lake?). So, my free ascent in the Steinke hood had no more than "Ho, Ho" before breaking the surface. Friends and I climbed the cliffs on the base and took scenic pictures--that was until the gendarmes surrounded us, accused us of being spies taking pictures of the torpedo-assembly shop below the cliffs--but hey, we got free film processing at least on the government dime. They determined our pictures were just of a bunch of young petty officers clowning around on some rocky cliffs, and nothing more. The Navy figured I didn't need Sub School (a big mistake, IMHO) since I was already rated, but I did get to train with my crew on John Marshall before we all climbed aboard a couple of C-130s out of Quonset Point for Holy Loch. Some of these details are a little shaky, I'm sure, but they'll probably become more clear as I grow even older and my short-term memory grows even shorter. I haven't thought about some of this stuff for decades. Wow. Of course, the Silent Service part of me doesn't discuss what happened once in Scotland or Spain. It took me almost two decades before I could stop myself from dipping my finger into every puddle of water I saw on a linoleum floor and tasting it, though. Some habits are hard to break.
 
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Anyone ever hear of a Bi-Tran Six trainer computer. I have a working unit that has actual working core memory. I power it up and se to run and all sorts of lights blink. There are 8 panels in it that can be raised to access test points. Everything seems to be working and it looks like something you may have seen in old 60's scifi movies. I was hoping to get more information on it as to figure out what I can do with it.

Yes. When I went to C&E Schools in the military we had a digital electronics class that had one of these. The instructors had us write simple programs for it. (each student) It is a binary 6 bit computer with core memory. You know, those itty bitty toriods? They have read, write and sense wires running through them. Any old computer book would show you something about how they work. I 'm not sure how many memory addresses there are but it's small compared to todays' modern standards. It has a finite set of instructions such as mod 2, move a,b , shift bit, and others like that at machine level. There are modes like program and run. You could use a port on it to program it or run it. Apparently you are able to run it from a program that is still in it or are you just playing around with the switches? I 'm guessing that you are looking for the instruction set? A schematic wouldn't hurt either. Hang on to it as long as you can or until you find a good museum to donate it to. It may be good to just power it up once in a while to keep the capacitors from drying out like they old tube amps. Take lots of pictures because these are rare. I don't know how many they ever built. Try to find the manufacturer name. It could help. That's about I can say right now. Sorry that I' m so late but I just had a thought today about it and so went searching and here you are. Great!
 
I learned about computers in the Army in 1974 on a Com-Tran Ten. I was digging though some old stuff and found a couple of manuals for it. I had to check online to see if anyone else remembered it. Apparently I'm not the only old guy online :)

OldLarry,

Do you still have any of those old manuals? I would love to be able to get hold of them (decent copies or scans would work too.) If you could send them to me via PM, or E-Mail (I'll PM my address to you,) that would be great.

Thanks,
 
OldLarry,

Do you still have any of those old manuals? I would love to be able to get hold of them (decent copies or scans would work too.) If you could send them to me via PM, or E-Mail (I'll PM my address to you,) that would be great.

Thanks,

I have two at least, "Technical Operations Manual for the Com-Tran Ten" which has installation procedures, the instruction set and a few low quality pictures. The second one just says "Com-Tran Ten table of contents" which has the schematics. I vaguely remember having another one but it must have crawled under a pile somewhere. I'll do some digging.
I'll try to scan them in. It probably will take a while but I'll put it relatively high on my list.
 
I haven't heard of this machine since 1975 when I was an electronics instructor in the Navy. I taught basic analog and digital electronics and primarily instructed new sailors digital electronics using the Bi Trans Six computer. I do not remember much about the machine other than we taught the students how to program, operate and troubleshoot ,his old workhorse. Basically, this is how we did it: first, we taught machine language and to write simple programs. Next, we had the student manually load his program into the computer one op word at a time. Finally,the student would run his program and see the results. What was neat about this was that each program line was computed one step at a time with the results showing in the eight different panels of leds. memory, adders, registers, etc.. You could actually see the numbers being added and subtracted one step at a time. It seems like the instructor was able to insert faulty transistors for troubleshooting Hope this helps
 
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...
 
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