On this channel, we dive into old school technology, focusing heavily on vacuum tubes. My primary goal is to build computing circuits based off the legendary machines of yesteryear, only with a slight modern twist. All the tubes will be operating with very low voltages on the plate, making the projects safe and easy to follow along with. So, lets grab our multimeters, some random tubes and a low voltage power supply and have fun!
Usagi Electric covers one of my main passions, while my other main passion can be found over on Usagi Motors.
In the fall of 1968, freshmen at Rose Polytechnic Institute (later Rose-Hulman Institute of Technology) were tasked with writing and running computer programs on a Bendix G15, using a numeric version of assembly language. After meeting that challenge, we were allowed to move on to using Fortran IV running on the school's IBM mainframe.
do u know much about bbc micro hard disks?? from 1982 or 1983?? i wanted to see one of the older bbc micro hard disks (8 inch type) thanks................
My first printer was a Commodore MPS-801. I frequently printed large assembly dumps. Set it to 16.7cpi condensed superscript. Can't remember how I reduced the line spacing but I think I managed to fit like 132 lines per page. The sound it made with those settings were those of an eldritch horror from the depths of the abyss. Had to point a fan at the print head to keep it from overheating.
I remember as a teenager these MFM drives ware a dime a dozen, as in they ware free. I had a lot of fun with them. About the RD52-A the black plastic arm that moves when the drive starts and stops, that the drive head lock. As the drives spin-up the air pushes on that arm moving it away to to unlock the drive heads and obviously the reverse as the drives spin down. This made the old "Park head" commands unnecessary.
There was a Capt. Fantastic pinball machine in the bowling alley down the street from where I grew up. I spent many hours and quarters at that bowling alley!
"Reforming" 60 year old electrolytics and saying they "look good" not just on this but on other stuff. One day somethings gonna short and blow something impossible to replace and you'll learn better.
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I’m probably not your intended audience. Actually most of what you said was gibberish to me. I trust you though I’m used to being the dumb one. That being said I’m an amateur radio operator and I love trying to see how these things work. It’s amazing to me, because I struggle to even classify this as a computer. So I’m utterly fascinated. I may have to come back and check in on the updates (ps you earned a sub) 😉
Just found this. in 1963, one of those at Cal Poly San Luis Obispo was my first introduction into computing. Then, I moved on to writing FORTRAN programs for the schools IBM 1620. Nice blast from the past in this series of videos.
I donated 3 of those printers back in the late 1990's to a friend when I was moving. No idea now what became of them, or the friend... I plan on getting a run of the mill dot matrix printer for a radio teletype setup around the first or second quarter of next year. Budget is tight, and other items have priority. I'm looking at some much quieter Epsons. Won't touch the new Epson crap, but the old dot matrix machines were good. Good luck in your adventures.
wheres the hard disc for the bbc micro ?? any1 know ?? i typed it into google but i cannot seem to find a photo of it anywhere (the older 8 inch hard discs) thanks..........
What an awesome contribution to computing history! We get in such a hurry for.the latest, greatest thing that it can be easy to fail to preserve things like this... but it was so important to human history, so getting it to work is fantastic.
Poor mans diode curve tracer is o-scope set to XY mode, power diode under test with x-former(s) and appropriate current limiting resistor. I would remove diode from board to test it to keep magic smoke from escaping other semiconductors. ( XY mode can be used for transistor curve tracing also, Ya just gotta have an Ah-Ha moment first...)
Make sure the brightness is down all the way if you're powering up a crt without the yoke hooked up. It will burn a hole in the center of the phosphorus in a second.
Be careful getting water on the back of the CRT. Moisture/water can cause the hermetic seal between the pins and the glass to fail. Hopefully you removed the plug and let it dry.
I really admire electromechanical devices from days gone by. All the operations worked out by hand. They are just an absolute marvel. Does the Capt. Fantastic pinball machine have anything to do with Elton John? Name used under licence perhaps?
Was the missing 011 of "0111" of "7" a checksum or torn off... or... did the bulb take some time to 'warm up' before registering data since those are the first 3 bits? I think I'm missing something here, but it's super cool you guys got this mess running again. Such good times. :)
You could have used some ribbon cable (like the gray stuff IDE cables are made of) to replace that flexible film. Would be easier to make fit than fiddling with solid core wire.
what a classic collection, you still find ones like this i bits of southern europe in small bars or resturants. they are great to play! I shold make space int he house ! lol.
AWESOME printers ! I have one been working since 1982 and still does. They came with several i/o options. Litton made the printhead positioning motors. I want to find a parallel i/o card for mine. I believe they even have a printhead alignment mode where they print a pattern on paper, one line.
You should bring these things up on a variac with a load equal to its current draw in series with it to keep from having a cap short and blow something when you first plug it in