Surprise! I was going to go release this Friday but opted for today as the video seemed to be all dialed in. Never thought I'd see one of these in person, let alone own one, but, here we are.
I was cleaning up my workshop yesterday and came across a framed picture of me taken in the early 1980's. I'm hunched over an ADM-3A working on some code in my bedroom, where my Imsai was installed at the time.
I enjoy when you provide history and context for these machines and the people around them. Maybe I'm weird but I find that far more engaging than watching people clean stuff.
Thanks! Yeah I kind of prefer to leave things as original as they can be. I feel like that gives future generations a proper sense of what the thing should look like. I always hate when I do something like go on a historical tour and they're like 'oh 99% of this is reconstructed'. I'd rather see original ruins.
@@TechTimeTraveller Yup I'd understand needing to do a little bit matinace work to make sure they are still in one piece but at 99 percent I feel like they should have to call it a replica at that point
Little known fact, the hjkl keys on the ADM 3A were also arrow keys. This is why Bill Joy chose those letters for cursor control in his VI Unix screen editor. It also was the reason those keys were used in the classic “rogue” game.
Not sure how "little known" it is, given that the arrows are printed right on those keys! :-) What was interesting to me here is that they started doing this right from the ADM-1.
@@MultiPetercool You should feel free to edit your post to clarify it if it's not saying what you wanted to say. I was responding to, "Little known fact, the hjkl keys on the ADM 3A were also arrow keys."
_Dance Dance Revolution_ uses that same order for its arrow receptors… I wonder if the developers were influenced by vi and the ADM-3A before it, or if it's a coïncidence.
The keys operate on the split-reed principle, primarily used by the defence industry, and Hewlett-Packard. the key has a tang separating two reeds when at rest, a hole in the tang allows the reeds to contact when pressed. Ultra-reliable, and positive feedback. And the key-caps were two-part injection moulded, so that the face could never abrade. Genius.
The kids call those "doubleshot keycaps" nowadays. It's nice that keyboard hacking and customization became a somewhat popular thing. It's so much easier these days to get quality parts that work the way you want.
Man, I am just loving this channel more and more! You REALLY are saving some Forgotten Machines such as this! This is the exact type of thing that is on my radar (and even this particular terminal model!), and I'm so glad you've saved and documented this one!
Do be careful with that moldy CRT - as the PVA glue breaks down, it will go liquid again and leak onto the PCB ruining it. If that system hasn't been turned on in a week there's no risk of shock. What is annoying is on that one, the mounting band is molded around the safety lens. The whole thing is epoxied together. I've not taken the lens off of a crt like that, but it would be a huge pain. You might want to put some foil or other containment under the crt to catch drips.
Yes I did find molasses like goo down on the pan and a few bits on the CRT. I wasn't sure if it was just industrial grime or the adhesive but you can see it pooling at the bottom. Pretty gross stuff. To my eye the band goes all around the crt and prevents access to a spot where you could insert a tool and with heat work on separating thr CRT. I've looked it over a few times and just can't see how you get in there.
@@TechTimeTraveller shango066 did good videos on repairing this, the band doesn’t seem to be tight like an implosion band so I think it would pry off easily
@@audiodood I realize this thread is 2 months old, but Shango specifically doesn't usually touch rectangular CRT cataracts, the dispersion of stress on the tube isn't the same as a "roundie" and once that implosion band comes off, you've basically got a glass bomb. I'd HIGHLY suggest sourcing a replacement, however that has to happen.
I don't know about the "risk of shock not being there if the system hasn't been turned on in a week" - I mean better safe than sorry and discharge it every time you do something like touching the tube (even if it has laid dormant for a while) - pretty easy to become a comic book villain if you trust a tube to be discharged.
@@lauram5905 he did it with a console a couple months ago, I think it was an admiral, the sealant had failed in exactly the same way also I think this crt probably has an implosion band so idk
Thank you so much for making these videos. This is way before my time, but it is the kinda computer I am fascinated with. I'm shocked to see it work at all. I'm pleased with how much care you took in fixing this old dinosaur up.
The scariest part of decataracting is by far the removal of the safety glass itself which has high risk of implosion. Solid state driver electronics especially of this era literally do not have enough power output to injure you while they're on - The high voltage is so low current that it would drag down to a level you probably wouldn't even be able to feel as soon as you touched it. The *real* scary part of this is that power supply, which has the nice risk of bursting into flames due to aging components or just the fact that it's poorly regulated mains supply from the 70s meaning there's a nonzero chance everything inside the unit is reference to mains at all times.
I had the ADM 2. Fished it out of a dumpster in 1998 or around that time. Gramps owned apartments, one of the tenants threw it out, and I was so intrigued by it that I kept it. Sadly it went to storage during a move, which my parents didn't pay off and I lost a whole bunch of old computers in there :( Hopefully I can re-buy and recover my collection of old systems. Interesting note, the ADM2 did not have an attached keyboard, it was an entirely separate unit that just butted against the screen.
In the mid 90's I worked for a steel mill industry and they were still using mainframes and serial terminals from the 70's and 80's very similar to those show in the video. I remember the IT guys struggling to keep them working. Their were painted in a very cool green-grey scheme. Then came the "micros" to replace the mainframe and it was a mess. All the workflow were tailored to the "green screen" terminals. The company bought a lot of IBM Aptivas but few peope had the experience to use Dos 6.22 and Win 3.11 (I had some experience because I was a PC user since the late 80's).
Regarding swapping the tube - yes there are many 12" tubes that will work. I think that one has the larger neck? If you see a tube with the same size neck and connector it should work 100%. It should have a 12v heater.
I'll bet that terminal will be a lot happier if you connect RTS and CTS together. Also DTR, DSR, and CD. Those are the common handshake lines needed to keep things happy. Also, don't expect to see anything on the screen unless you're running half-duplex or have connected Send Data and Receive Data together.
Yeah I was trying to figure out what mode it was set for in terms of duplex or send page.. but the switch is absolutely smashed. When I get my current project done I'm going to do some continuity tests and see how it was set.. and then either replace the switch or manually jumper it to the setting I want.
Time to fix the CRT cataracts. I fixed a similar problem with my ADM-3A. Just plenty of heat and acetone and you can make the screen like new after you remove the adhesive between the tube and front glass.
@@TechTimeTraveller On mine the implosion band doubles as the frame that mounts the tube up against the face of the cabinet. On yours it looks like there's a frame holding the front lens in place, and it might have a separate implosion band around the tube behind it? It looks like if you just unscrew the nickel-colored frame then it will expose the tube, then you can start working on fixing the cataracts. Check out John Sutley's video called "CRT Cataracts: VTV" where he shows his process of fixing the cataracts on an ADM-3A.
Never really gave terminals a second glance in terms of collecting, it’s cool to see the wide variety though, I think I prefer the blue colour scheme:) I take it you could hook up to a modern machine with a terminal emulator?
Yup. Although in my case once it's restored I probably would use it with my other vintage equipment. I have a lot of serial based machines in my collection and this terminal actually makes me want to fire them up more.
I love this little guy (little lol). The form factor from the the front is just gorgeous and then you see it from the side and bam its a long boi. Also I think that red is original or at least very well done by secondary user, because there is labeling over the top and it appears very cleanly done in video (age issues aside). I also don't think that it isn't unlikely that whatever company bought it wanted it match the design of it's location. The idea of a sleek beautiful office didn't start with modern silicon valley tech startups. The 70s in particular were big into design elements that we would now call retro futurism. So I could totally see that red being intended to match a carpet or as accent color.
I'd love ANY "dumb" terminal I could get my hands on... but this one is truly a beauty. Back in my youth, I always wanted a hex keypad and was always disappointed by "these business machines" with only a decimal numeric pad.
Boo RUclips, for throwing away my comment entirely so I have to type it again. An advantage of the ADM-3A discrete design was that with a simple modification it could reliably handle 38.4 kbps while most 8080-based terminals of the day would drop bytes at 9.6 kbps.
What about using a heat gun to melt the glue and remove the lens? If you don't linger in one place too long and evenly heat the lens, it ought to just pop right off. At that point I'd give it a good cleaning, and maybe try to reinstall it without adhesive. As for discharging the CRT, as others have indicated, there's a pretty good chance it'll discharge itself after a short while (anywhere from 30 minutes to a couple days). Even if it doesn't, the single-handed method used by the vacuum tube guys can make it relatively safe. Basically, ground a metal probe of some sort (like a thin screwdriver) to the chassis. Then, using one hand only, insert the screw driver under the rubber boot for the high voltage line until you touch the pin. If it's discharged, nothing happens. Otherwise, you'll hear a crack, and it'll be done with. This method is considered safer because, for most electric shocks, the part that makes it "lethal" is when electricity arcs across your heart, and the current stops your heart. Presuming you're not doing this barefoot while standing in a pool of water (don't do that), the only way this can really happen is if both hands complete the circuit, with anode and cathode in opposite hands. You may _potentially_ (pun intended) still get a zap off it, and it might not feel good, but it's not likely to kill you. This info sourced from numerous RUclipsrs smarter than I, notably Big Clive (BigCliveDotCom), Mr. Carlson's Lab, Adrian's Digital Basement, and a few others. Big Clive even went so far as to demonstrate electricity is not necessarily lethal, by deliberately shorting himself across 240v AC mains through a potentiometer. (Not something _I_ would do, but it definitely gets the point across. 😳) 👍️
I have a 1969 first gen 18" Trinitron with this same type of cataracting but not as severe, it looks as though there's some kind of laminate as the black spots aren't all on the same plane. I figured as it looks awful there's really not a lot to lose by trying to remove it. I was wondering if soaking the tube face down in some water for a while could help soften the adhesives.
What I'm having trouble with is there is a metal band all the way around that covers the seam between the crt glass and the implosion shield. I've been looking at it but cannot figure out how it would come off.
@@TechTimeTraveller My bet is they'll have used a polyurethane goop to seal the band on, I think even heat all the way around and see if anything starts to move would be the way I'd go.
Back when I worked for Bell Telephone Laboratories. I used a terminal that resembled a blue dot matrix printer with a keyboard. I don't recall the type of terminal it was. but it was back in the days before the very first Macintosh computer came out.
Been after a terminal for a while now, as you said they want way too much for them, scary for me as I once worked in a repair shop at a telco, where all the terminals got fixed. back then all my efforts were towards building up my TRS-80 system and never thought of acquiring a terminal (or a telex machine, that I also worked on), darn
I managed to find a BT Telex machine on ebay a few years back, unfortunately it didn't have the keyboard. It has a 5 pin DIN connector but I don't know if it just uses an AT type keyboard or a proprietary one. So as of yet I've not been able to do anything with it.
switches on that look like reed switches, which are basically indestructible. Much better than having to refoam a f&f keyboard EDIT: lol you just said that in the video after I got this typed up
At tike code 26:40 you mention that the terminal has the capability of doing reverse image. Did you attempt to activate/deactivate that function? I didn't see that in the video. Outstanding video as well, than you for letting us glimpse neat hardware we will never get to touch.
I suggest you send control-G from the PC to the terminal. You've demonstrated that the computer beeps when you type control-G locally. When you send control-G from your PC to the Adm-1 you'll know you have the RS-232 handshake, baud rate, and stop-bits sorted out when it goes through and you hear the beep. Getting the character generator right will be another matter. As for the danger of high-voltage, you just have to discharge all the high voltage capacitors as a TV repair guy (e.g. Mr. Carlson) can describe.
I worked for LSi during the early '80s, but preferred the VT-100. My Z-89 computer resembled the ADM terminals. Its architecture was interesting. It had an H-19 terminal with a 2nd PCB for a single-board Z-80 alongside the terminal board.
Nice! In 1976 my high school had 2 Altairs, a teletype, and an ADM-3. So space age! BTW, many of your videos have good aviation references. Are you into aviation?
Man your high school must've been pretty awesome! I've heard of schools having DEC or Commodore or Apple equipment.. but not MITS. Neat! Yes I'm an aviation enthusiast. Never actually tried to learn to fly but I find it fascinating. My favorite channel is Mentour Pilot.
The ADM 3 looks like the terminal display used on some old CNC PCB drill machines going by the name of Excellon. Maybe look for old PCB equipment for these machines.
for old stuff I use a home made box, its a metal outlet box with a cord and a GFCI wired up correctly so if nasty electrons are imbalanced from in to out it will trip ... plus you have a kill switch (the test button) On mine I use a 4 gang box and a light switch before the GFCI marked (in sharpie of course) OH SHI* both are the rectangle holes on the metal face plate cause GFCI and I prefer a paddle style OH SHI* switch over a toggle, its easier to slap in the event of .... rapid oxidation
@@TechTimeTraveller I looked for all ADM LSI and Lear Siegler ADMs on WorthPoint, nothing sad to say. Anyway, that's my only suggestion for your historical documentation, but it does not detract from your fantastic restoration journey...please keep up the great work on that! When might we see an update to that one?
Ah the "ambience'" ... Liberace...and ...a Prawn Cocktail with lettuce and Thousand Island dressing...by candle light...all while discharging the Cap...
You can eliminate CRT cataracts if you use a heatgun. Theres plenty of vids on youtube. The point is to get the rtv type adhesive warm enough and going from the center outwards evenly warming it up forcing airbubbles out. Never heard of discharging the CRT. Just do it carefully.
I've watched the videos. Unfortunately to even get to that step I have to overcome my fear od getting zapped. I'm working on learning how to discharge safely and be sure it's discharged. I've gotten bitten a few times.
Nice colour. With regards to the CRT, you are better off looking for a new tube. Just taking the metal band off runs the risk of it exploding in a shower of glass.
Can you speculate as to WHY you believe that this particular one was painted red by it's end-user at any point? Reference 4:29 And 5:07 I am of the belief that the blue undercoat is the original LSI color, and the red is spray paint by an end user/decorator at some point. Any more thoughts on that? Tell us more about the previous owner, and how they got it!
My guess is it was a custom job lot that the Systems Corp did for a client or maybe did for every terminal they supplied. One thing throwing me about the paint is all the other terminals I've seen are white on outside and blue around keyboard and CRT.. but this one appears to have the blue underneath the red around the outside.
@@TechTimeTraveller Excellent deduction, you're probably quite right! About where the blue is found, I think I found one where the whole thing is light blue, except the area around the keyboard and CRT, which is a darker shade of blue. But I can't share the URL unfortunately, as RUclips blocks those comments if I do. Perhaps I'll find another way to share it.
why not try transparent led switch keyboard, transparent membrane that flexes and when its down, it blocks the led = switch on, then rise finger, not blocked, yes need room/solar lighting to work, or keyboard light next to the keys, two led keyboard, one rgb for backlight, the other as the light detector
I love your thoroughly researched history videos and the calming tone of your channel. Great work you've been doing, and very enjoyable. I just regret that, on the restoration side of things, you have all the way to go! Which is a pity, given that you do handle -- i.e. open, disassemble, poke around, etc., which alone can destroy a piece if not done properly -- rare and historically significant pieces. And if these pieces aren't treated properly by the person who just acquired them, probably they won't be treated properly by anyone until you sell them again, presumably decades from now, when it may be too late. The restorers among your audience will cringe a little here and there.
Well first, thank you. Second.. I'm not sure what you're taking issue with specifically. I've restored over 40 machines from non working to working status. That includes an Apple Lisa with catastrophic battery leakage, a defunct digital group z80, some non working OSI gear. I take appropriate precautions for static (off camera), and check power supplies etc with my scope. What am I doing wrong? This is just a cursory assessment and cleanup video. More serious restoration work will come later.
@@TechTimeTraveller Apologies if it got across too strong, it was not the intention. You're not destructive at all (some others are). It's good to hear that you do take ESD precautions, even though they aren't visible on camera. Those are critical when touching any semiconductor, even in-circuit. It's not for me to say what is right or wrong, but I can share with you how I would go about things. I'd not take the machine apart just for a cursory clean, then put it back together for a relatively lengthy testing session. Once the machine is open, beyond a thorough visual inspection for corrosion, bulging or electrolyte-leaking caps, missing components, charred resistors, etc., checking all caps with an in-circuit ESR meter is important before turning the machine on for more than a few seconds, or you could cause serious problems. Caps with large ESR tend to have dried electrolyte and won't reform properly with the machine on. The oxide may crack fully, potentially causing devastating DC shorts. Checking forward voltages (with the machine off) on diodes and transistors against specs is also a good idea before lengthy power-on periods, as marginal parts can short after a few minutes of usage. When you do turn the machine on, I'd measure the power rail voltages immediately, as the machine may work with voltages beyond tolerance, but will also damage itself. You won't see this if you turn the machine on with the case in place, without measuring the voltages and ripple on the power rails. By the way, excessive ripple is common and can damage a machine after only minutes of use. You want to measure it with an oscilloscope in AC coupling, and ensure ripple on, say, a 5V rail is under 50mV. Blowing dust off the circuit boards with an ESD-safe, high-pressure air blower also helps prevent arcing induced by humidity-rich dust particles, lint, etc. It may also be a good idea to preventatively swap out components that operate under high heat (such as pass transistors, linear voltage regulators, rectifying diodes, high voltage drivers, etc.), as electromigration is accelerated by heat and renders those components deceptively marginal. If those components are in the power supply, when they go they may take the entire digital board with them, so it's often a good idea to reconstruct the entire power supply circuit before turning the machine on for more than a few seconds, if you can find new but original parts (most power supply components from the 70s are, unbelievably enough, still manufactured today). The original CRT looks to be in order (at least on your video I couldn't see any burn-in, and the phosphor seems to be still quite bright), you don't need to throw it away just because of the cataracts. You can remove the safety glass to sort it out. The chances that you will blow the tube are relatively small (1 in 5?) if you heat it slowly and uniformly and, in any case, better than throwing away the original tube. Red also clearly isn't the original color of the case, as one can see the original light blue showing where the red has pealed off, so I'd surely try very light, low-pressure sand-blasting to remove the after-market layer and then respray with the original color. The keys may also deserve some retrobrighting and UV-protection. Anti-corrosion treatment of ICs and port connectors (with electronics detergent and something like DeoxIT D5) will also help preserve them. And so on. Keep in mind that those machines were never designed to be turned on 50 years later, even in the best case scenarios! But I don't mean that you absolutely have to do all this stuff (although, if you can and feel like it, it's definitely a good idea), the intent is just to give you examples. Keep up the excellent work and thanks for the great content!
Thanks yes no worries. I watched some of your videos and generally was impressed with your thoroughness. The issue with me is I often do things and don't video or don't remember to video/explain. Part of the youtube learning process. In this case, doing my visual, DMM and scope inspections just didn't work with the camera, I kept getting in the way. I probably should be more forceful in saying 'hey, I did this off camera, don't try this at home without doing a b and c', but I forget sometimes, or I feel like there's debate on what proper procedure is and don't feel confident to say 'you must do this'. I've been collecting about 20 years and I've developed an appropriate level of caution. In the old days I would have just plugged something in and most times got away with it but sometimes didn't. These days I trust nothing, I check the wiring out under good light, I look for cold solder joints, breaks, signs of fire, leaks. I always test power supplies as thoroughly as I can both to preserve the equipment and also for safety reasons. For this ADM-1 I did all that, and I had spoken with the seller who insisted it had been powered on without incident before. After verifying there were no issues with power going to the board and that the CRT seemed alright, I decided some short attempts to start it were okay. That said, it will undergo a deeper restoration including hopefully figuring out how to get the implosion shield safely off to clean and remove the cataracts. But for now I just wanted to show folks something that you don't see every day on RUclips. Anyway I appreciate your comment, it did make me think.
Never thought of that! Sometimes if I can get a couple off I can carefully use my chip puller when they're really stuck on there. But usually with enough pressure I can do it without any tools.
Good grief if I see another seller say something "powers on" I'm going to jump through the internet and eat their limbs. You DON'T plug in electronics with unknown provenance. It can and will destroy them in short order, even if it seems to "power on". Especially valve era stuff, but it'll very likely happen to digital stuff too once all the caps go completely bad.
This thing is really interesting, but it has some very serious problems. I think you are going to have to go thru the main logic board one chip at a time, not to mention the video circuits.
Fun video. Quick suggestion, you may want to balance your audio a bit more. Your voice over is significantly lower than the rest of the audio. So when you switch from your soothing baritone voice to a movie insert or live recording it's a bit shocking.
Thank you. Yes, as a novice my 'skills' with audio have been evolving and sometimes things that sound right to me don't sound quite right to others. Never thought audio would be as hard as it is. Bugger of it is I adjusted the volume downwards are the segments that jump out several times and thought it was under control. Although I did pick a movie sequence where the character kind of raises his voice abruptly.
Surprise! I was going to go release this Friday but opted for today as the video seemed to be all dialed in. Never thought I'd see one of these in person, let alone own one, but, here we are.
What an awesome machine! Can't wait to see more on the rig.
It's been a few years, did you ever get any further ron this project?
I was cleaning up my workshop yesterday and came across a framed picture of me taken in the early 1980's. I'm hunched over an ADM-3A working on some code in my bedroom, where my Imsai was installed at the time.
I enjoy when you provide history and context for these machines and the people around them. Maybe I'm weird but I find that far more engaging than watching people clean stuff.
Not weird at all my dude I'm the same way I'm much more interested in the history of these things as well
isnt that why people love these old things? aside from possibly being nostalgic of one you had back in the day
You find some fascinating machines to show!
That thing looks SO good in red and black.
I really like that you preserve the machine without trying to make it look brand new.
Thanks! Yeah I kind of prefer to leave things as original as they can be. I feel like that gives future generations a proper sense of what the thing should look like. I always hate when I do something like go on a historical tour and they're like 'oh 99% of this is reconstructed'. I'd rather see original ruins.
@@TechTimeTraveller Yup I'd understand needing to do a little bit matinace work to make sure they are still in one piece but at 99 percent I feel like they should have to call it a replica at that point
Little known fact, the hjkl keys on the ADM 3A were also arrow keys. This is why Bill Joy chose those letters for cursor control in his VI Unix screen editor. It also was the reason those keys were used in the classic “rogue” game.
And the order left-down-up-right was retained in the Sinclair ZX Spectrum cursor keys: caps shift + 5, 6, 7 and 8 .....
Not sure how "little known" it is, given that the arrows are printed right on those keys! :-)
What was interesting to me here is that they started doing this right from the ADM-1.
@@Curt_Sampson I think I was referring to the VI editor rather than the ADM 3-A per se.
@@MultiPetercool You should feel free to edit your post to clarify it if it's not saying what you wanted to say. I was responding to, "Little known fact, the hjkl keys on the ADM 3A were also arrow keys."
_Dance Dance Revolution_ uses that same order for its arrow receptors… I wonder if the developers were influenced by vi and the ADM-3A before it, or if it's a coïncidence.
I remember the ADM's. They were very popular with airline reservation desks at airports.
The keys operate on the split-reed principle, primarily used by the defence industry, and Hewlett-Packard.
the key has a tang separating two reeds when at rest, a hole in the tang allows the reeds to contact when pressed.
Ultra-reliable, and positive feedback.
And the key-caps were two-part injection moulded, so that the face could never abrade.
Genius.
The kids call those "doubleshot keycaps" nowadays. It's nice that keyboard hacking and customization became a somewhat popular thing. It's so much easier these days to get quality parts that work the way you want.
Man, I am just loving this channel more and more! You REALLY are saving some Forgotten Machines such as this! This is the exact type of thing that is on my radar (and even this particular terminal model!), and I'm so glad you've saved and documented this one!
Do be careful with that moldy CRT - as the PVA glue breaks down, it will go liquid again and leak onto the PCB ruining it.
If that system hasn't been turned on in a week there's no risk of shock. What is annoying is on that one, the mounting band is molded around the safety lens. The whole thing is epoxied together. I've not taken the lens off of a crt like that, but it would be a huge pain.
You might want to put some foil or other containment under the crt to catch drips.
Yes I did find molasses like goo down on the pan and a few bits on the CRT. I wasn't sure if it was just industrial grime or the adhesive but you can see it pooling at the bottom. Pretty gross stuff.
To my eye the band goes all around the crt and prevents access to a spot where you could insert a tool and with heat work on separating thr CRT. I've looked it over a few times and just can't see how you get in there.
@@TechTimeTraveller shango066 did good videos on repairing this, the band doesn’t seem to be tight like an implosion band so I think it would pry off easily
@@audiodood I realize this thread is 2 months old, but Shango specifically doesn't usually touch rectangular CRT cataracts, the dispersion of stress on the tube isn't the same as a "roundie" and once that implosion band comes off, you've basically got a glass bomb. I'd HIGHLY suggest sourcing a replacement, however that has to happen.
I don't know about the "risk of shock not being there if the system hasn't been turned on in a week" - I mean better safe than sorry and discharge it every time you do something like touching the tube (even if it has laid dormant for a while) - pretty easy to become a comic book villain if you trust a tube to be discharged.
@@lauram5905 he did it with a console a couple months ago, I think it was an admiral, the sealant had failed in exactly the same way also I think this crt probably has an implosion band so idk
Thank you so much for making these videos. This is way before my time, but it is the kinda computer I am fascinated with. I'm shocked to see it work at all. I'm pleased with how much care you took in fixing this old dinosaur up.
One year later...and I'm still SOOO glad that you are the one who bought this!
Great video! What an awesome little terminal. Looking forward to Pt2.
The scariest part of decataracting is by far the removal of the safety glass itself which has high risk of implosion. Solid state driver electronics especially of this era literally do not have enough power output to injure you while they're on - The high voltage is so low current that it would drag down to a level you probably wouldn't even be able to feel as soon as you touched it.
The *real* scary part of this is that power supply, which has the nice risk of bursting into flames due to aging components or just the fact that it's poorly regulated mains supply from the 70s meaning there's a nonzero chance everything inside the unit is reference to mains at all times.
400V electrolytic capacitors can hold a lot of spark for a surprising time.
I had the ADM 2. Fished it out of a dumpster in 1998 or around that time. Gramps owned apartments, one of the tenants threw it out, and I was so intrigued by it that I kept it. Sadly it went to storage during a move, which my parents didn't pay off and I lost a whole bunch of old computers in there :( Hopefully I can re-buy and recover my collection of old systems. Interesting note, the ADM2 did not have an attached keyboard, it was an entirely separate unit that just butted against the screen.
I love the external numeric keypad! That has to be the oldest example I have ever seen.
I somehow find it comforting that I'm not the only weirdo who doesn't like the feel of micro fiber towels :D
In the mid 90's I worked for a steel mill industry and they were still using mainframes and serial terminals from the 70's and 80's very similar to those show in the video.
I remember the IT guys struggling to keep them working. Their were painted in a very cool green-grey scheme.
Then came the "micros" to replace the mainframe and it was a mess. All the workflow were tailored to the "green screen" terminals. The company bought a lot of IBM Aptivas but few peope had the experience to use Dos 6.22 and Win 3.11 (I had some experience because I was a PC user since the late 80's).
I got an ADM-3A through local pick-up while visiting my parents a while back. :)
Regarding swapping the tube - yes there are many 12" tubes that will work. I think that one has the larger neck? If you see a tube with the same size neck and connector it should work 100%. It should have a 12v heater.
I'll bet that terminal will be a lot happier if you connect RTS and CTS together. Also DTR, DSR, and CD. Those are the common handshake lines needed to keep things happy. Also, don't expect to see anything on the screen unless you're running half-duplex or have connected Send Data and Receive Data together.
Yeah I was trying to figure out what mode it was set for in terms of duplex or send page.. but the switch is absolutely smashed. When I get my current project done I'm going to do some continuity tests and see how it was set.. and then either replace the switch or manually jumper it to the setting I want.
Time to fix the CRT cataracts. I fixed a similar problem with my ADM-3A. Just plenty of heat and acetone and you can make the screen like new after you remove the adhesive between the tube and front glass.
How do you get around the metal rim around the tube?
@@TechTimeTraveller On mine the implosion band doubles as the frame that mounts the tube up against the face of the cabinet. On yours it looks like there's a frame holding the front lens in place, and it might have a separate implosion band around the tube behind it? It looks like if you just unscrew the nickel-colored frame then it will expose the tube, then you can start working on fixing the cataracts. Check out John Sutley's video called "CRT Cataracts: VTV" where he shows his process of fixing the cataracts on an ADM-3A.
Great video! I was just recommended your channel. Love the content!
Holy poop, this is literally the terminal from Fallout.
WOW! These early terminals were built like tanks! This thing looks invincible!
Great addition to your collection! When will you do part 2? Thanks for sharing!!
Never really gave terminals a second glance in terms of collecting, it’s cool to see the wide variety though, I think I prefer the blue colour scheme:) I take it you could hook up to a modern machine with a terminal emulator?
Yup. Although in my case once it's restored I probably would use it with my other vintage equipment. I have a lot of serial based machines in my collection and this terminal actually makes me want to fire them up more.
How cool! I hope to see later videos with it working fully. :-)
Don't feel too bad about the space bar, as it was repairable. I dropped a TI-99/4a keyboard and it was trash in an instant.
This would look fantastic on commissioner Gordans desk
I love this little guy (little lol). The form factor from the the front is just gorgeous and then you see it from the side and bam its a long boi. Also I think that red is original or at least very well done by secondary user, because there is labeling over the top and it appears very cleanly done in video (age issues aside). I also don't think that it isn't unlikely that whatever company bought it wanted it match the design of it's location. The idea of a sleek beautiful office didn't start with modern silicon valley tech startups. The 70s in particular were big into design elements that we would now call retro futurism. So I could totally see that red being intended to match a carpet or as accent color.
I'd love ANY "dumb" terminal I could get my hands on... but this one is truly a beauty.
Back in my youth, I always wanted a hex keypad and was always disappointed by "these business machines" with only a decimal numeric pad.
Boo RUclips, for throwing away my comment entirely so I have to type it again.
An advantage of the ADM-3A discrete design was that with a simple modification it could reliably handle 38.4 kbps while most 8080-based terminals of the day would drop bytes at 9.6 kbps.
Looks like a computer Tonka would make.
Really glad your ad brought me to your channel
Is that the terminal that the (in)famous vi editor was written on? Using the HJKL keys for cursor navigation seems familiar.
I feel like that may have been one of the DEC VT terminals. I've been trying to get the answer to that myself.
@@TechTimeTraveller I've been told that the ADM-3A is the terminal in question that resulted in vi's cursor key choices.
What about using a heat gun to melt the glue and remove the lens? If you don't linger in one place too long and evenly heat the lens, it ought to just pop right off. At that point I'd give it a good cleaning, and maybe try to reinstall it without adhesive.
As for discharging the CRT, as others have indicated, there's a pretty good chance it'll discharge itself after a short while (anywhere from 30 minutes to a couple days). Even if it doesn't, the single-handed method used by the vacuum tube guys can make it relatively safe. Basically, ground a metal probe of some sort (like a thin screwdriver) to the chassis. Then, using one hand only, insert the screw driver under the rubber boot for the high voltage line until you touch the pin. If it's discharged, nothing happens. Otherwise, you'll hear a crack, and it'll be done with.
This method is considered safer because, for most electric shocks, the part that makes it "lethal" is when electricity arcs across your heart, and the current stops your heart. Presuming you're not doing this barefoot while standing in a pool of water (don't do that), the only way this can really happen is if both hands complete the circuit, with anode and cathode in opposite hands. You may _potentially_ (pun intended) still get a zap off it, and it might not feel good, but it's not likely to kill you.
This info sourced from numerous RUclipsrs smarter than I, notably Big Clive (BigCliveDotCom), Mr. Carlson's Lab, Adrian's Digital Basement, and a few others. Big Clive even went so far as to demonstrate electricity is not necessarily lethal, by deliberately shorting himself across 240v AC mains through a potentiometer. (Not something _I_ would do, but it definitely gets the point across. 😳) 👍️
That's a hansome unit. Looks like bit 7 (0100 0000) is stuck high.
I love this channel, you deserve more subscribers dude
The 2513 was also used in the Apple I and early Apple II.
Hah! that 'LSI' always fooled me. It also stood for "Large Scale Integration" - ironic initials for a terminal full of 7400 TTL!
I have a 1969 first gen 18" Trinitron with this same type of cataracting but not as severe, it looks as though there's some kind of laminate as the black spots aren't all on the same plane. I figured as it looks awful there's really not a lot to lose by trying to remove it. I was wondering if soaking the tube face down in some water for a while could help soften the adhesives.
What I'm having trouble with is there is a metal band all the way around that covers the seam between the crt glass and the implosion shield. I've been looking at it but cannot figure out how it would come off.
@@TechTimeTraveller My bet is they'll have used a polyurethane goop to seal the band on, I think even heat all the way around and see if anything starts to move would be the way I'd go.
Wow, that startup "beep" is horrifying 🙀
Back when I worked for Bell Telephone Laboratories. I used a terminal that resembled a blue dot matrix printer with a keyboard. I don't recall the type of terminal it was. but it was back in the days before the very first Macintosh computer came out.
Discharging a crt ...is something yiu should've learned years ago , its kind if essential given the toys you've chosen to play with
If you are planning to switch the CRT you could try and experiment on it to see if you can get it open somehow.
Been after a terminal for a while now, as you said they want way too much for them, scary for me as I once worked in a repair shop at a telco, where all the terminals got fixed. back then all my efforts were towards building up my TRS-80 system and never thought of acquiring a terminal (or a telex machine, that I also worked on), darn
I managed to find a BT Telex machine on ebay a few years back, unfortunately it didn't have the keyboard. It has a 5 pin DIN connector but I don't know if it just uses an AT type keyboard or a proprietary one. So as of yet I've not been able to do anything with it.
Curious about the color. I wonder if it was used for a "hotline" - either for real or on-screen.
Greetings from Karachi, Pakistan.
I still have an ADM5, working. Would that be worth something?
For sure. Probably at least $300-500.
Wow, can't believe This Dream Machine ripped off the Wii Mini color scheme 🙃
switches on that look like reed switches, which are basically indestructible. Much better than having to refoam a f&f keyboard
EDIT: lol you just said that in the video after I got this typed up
At tike code 26:40 you mention that the terminal has the capability of doing reverse image. Did you attempt to activate/deactivate that function? I didn't see that in the video. Outstanding video as well, than you for letting us glimpse neat hardware we will never get to touch.
I suggest you send control-G from the PC to the terminal. You've demonstrated that the computer beeps when you type control-G locally. When you send control-G from your PC to the Adm-1 you'll know you have the RS-232 handshake, baud rate, and stop-bits sorted out when it goes through and you hear the beep. Getting the character generator right will be another matter. As for the danger of high-voltage, you just have to discharge all the high voltage capacitors as a TV repair guy (e.g. Mr. Carlson) can describe.
I worked for LSi during the early '80s, but preferred the VT-100. My Z-89 computer resembled the ADM terminals. Its architecture was interesting. It had an H-19 terminal with a 2nd PCB for a single-board Z-80 alongside the terminal board.
Nice! In 1976 my high school had 2 Altairs, a teletype, and an ADM-3. So space age!
BTW, many of your videos have good aviation references. Are you into aviation?
Man your high school must've been pretty awesome! I've heard of schools having DEC or Commodore or Apple equipment.. but not MITS. Neat!
Yes I'm an aviation enthusiast. Never actually tried to learn to fly but I find it fascinating. My favorite channel is Mentour Pilot.
@@TechTimeTraveller The teacher, Mr Dyk, wrote an article about it in MITS Computer Notes for 7/77.
@@TechTimeTraveller Also 6/79 Kilobaud.
@@TechTimeTraveller and 6/77 Kilobaud.
The ADM 3 looks like the terminal display used on some old CNC PCB drill machines going by the name of Excellon. Maybe look for old PCB equipment for these machines.
The RED TERMINAL is the one which the Evil Supercomputer uses to communicate with the Worried Scientists in the cheaply made Sci-Fi Film.
for old stuff I use a home made box, its a metal outlet box with a cord and a GFCI wired up correctly so if nasty electrons are imbalanced from in to out it will trip ... plus you have a kill switch (the test button) On mine I use a 4 gang box and a light switch before the GFCI marked (in sharpie of course) OH SHI* both are the rectangle holes on the metal face plate cause GFCI and I prefer a paddle style OH SHI* switch over a toggle, its easier to slap in the event of .... rapid oxidation
I am comfortable with discharging crts and I'd still sooner try for a replacement tube than mess around trying to fix cateracting
I think it needs a new tube...
Is this the same LSI that produces raid controllers today?
No.
yeah i was wondering the same thing..
Just imagine how many people have interacted with it over time and how many of those are now dead. probably even the people that built it.
18:43 Did you happen to archive the eBay auction that you got this from? That would be a cool part of it's history to see documented!
If it is archived it'd be on Worthpoint.. I don't think I actually saved it unfortunately.
@@TechTimeTraveller I looked for all ADM LSI and Lear Siegler ADMs on WorthPoint, nothing sad to say. Anyway, that's my only suggestion for your historical documentation, but it does not detract from your fantastic restoration journey...please keep up the great work on that! When might we see an update to that one?
I too want a "rub out" key
Ah the "ambience'" ... Liberace...and ...a Prawn Cocktail with lettuce and Thousand Island dressing...by candle light...all while discharging the Cap...
btw you can have someone clean out that cataract on the screen (or you can do it yourself)
wait the fallout terminal is real?
That screen looks like it has a severe case of Cateract, as shango066 would say.
You can eliminate CRT cataracts if you use a heatgun. Theres plenty of vids on youtube. The point is to get the rtv type adhesive warm enough and going from the center outwards evenly warming it up forcing airbubbles out. Never heard of discharging the CRT. Just do it carefully.
I've watched the videos. Unfortunately to even get to that step I have to overcome my fear od getting zapped. I'm working on learning how to discharge safely and be sure it's discharged. I've gotten bitten a few times.
Next time can you fix the cataracts?
Nice colour. With regards to the CRT, you are better off looking for a new tube. Just taking the metal band off runs the risk of it exploding in a shower of glass.
Can you speculate as to WHY you believe that this particular one was painted red by it's end-user at any point? Reference 4:29 And 5:07 I am of the belief that the blue undercoat is the original LSI color, and the red is spray paint by an end user/decorator at some point. Any more thoughts on that? Tell us more about the previous owner, and how they got it!
My guess is it was a custom job lot that the Systems Corp did for a client or maybe did for every terminal they supplied. One thing throwing me about the paint is all the other terminals I've seen are white on outside and blue around keyboard and CRT.. but this one appears to have the blue underneath the red around the outside.
@@TechTimeTraveller Excellent deduction, you're probably quite right! About where the blue is found, I think I found one where the whole thing is light blue, except the area around the keyboard and CRT, which is a darker shade of blue. But I can't share the URL unfortunately, as RUclips blocks those comments if I do. Perhaps I'll find another way to share it.
Thanks
why not try transparent led switch keyboard, transparent membrane that flexes and when its down, it blocks the led = switch on, then rise finger, not blocked, yes need room/solar lighting to work, or keyboard light next to the keys, two led keyboard, one rgb for backlight, the other as the light detector
Visionary indeed, knew that computers in the future would primarily be used for porn. Had a “rub out” key even back then
I love your thoroughly researched history videos and the calming tone of your channel. Great work you've been doing, and very enjoyable. I just regret that, on the restoration side of things, you have all the way to go! Which is a pity, given that you do handle -- i.e. open, disassemble, poke around, etc., which alone can destroy a piece if not done properly -- rare and historically significant pieces. And if these pieces aren't treated properly by the person who just acquired them, probably they won't be treated properly by anyone until you sell them again, presumably decades from now, when it may be too late. The restorers among your audience will cringe a little here and there.
Well first, thank you. Second.. I'm not sure what you're taking issue with specifically. I've restored over 40 machines from non working to working status. That includes an Apple Lisa with catastrophic battery leakage, a defunct digital group z80, some non working OSI gear. I take appropriate precautions for static (off camera), and check power supplies etc with my scope. What am I doing wrong? This is just a cursory assessment and cleanup video. More serious restoration work will come later.
@@TechTimeTraveller Apologies if it got across too strong, it was not the intention. You're not destructive at all (some others are). It's good to hear that you do take ESD precautions, even though they aren't visible on camera. Those are critical when touching any semiconductor, even in-circuit. It's not for me to say what is right or wrong, but I can share with you how I would go about things. I'd not take the machine apart just for a cursory clean, then put it back together for a relatively lengthy testing session. Once the machine is open, beyond a thorough visual inspection for corrosion, bulging or electrolyte-leaking caps, missing components, charred resistors, etc., checking all caps with an in-circuit ESR meter is important before turning the machine on for more than a few seconds, or you could cause serious problems. Caps with large ESR tend to have dried electrolyte and won't reform properly with the machine on. The oxide may crack fully, potentially causing devastating DC shorts. Checking forward voltages (with the machine off) on diodes and transistors against specs is also a good idea before lengthy power-on periods, as marginal parts can short after a few minutes of usage. When you do turn the machine on, I'd measure the power rail voltages immediately, as the machine may work with voltages beyond tolerance, but will also damage itself. You won't see this if you turn the machine on with the case in place, without measuring the voltages and ripple on the power rails. By the way, excessive ripple is common and can damage a machine after only minutes of use. You want to measure it with an oscilloscope in AC coupling, and ensure ripple on, say, a 5V rail is under 50mV. Blowing dust off the circuit boards with an ESD-safe, high-pressure air blower also helps prevent arcing induced by humidity-rich dust particles, lint, etc. It may also be a good idea to preventatively swap out components that operate under high heat (such as pass transistors, linear voltage regulators, rectifying diodes, high voltage drivers, etc.), as electromigration is accelerated by heat and renders those components deceptively marginal. If those components are in the power supply, when they go they may take the entire digital board with them, so it's often a good idea to reconstruct the entire power supply circuit before turning the machine on for more than a few seconds, if you can find new but original parts (most power supply components from the 70s are, unbelievably enough, still manufactured today). The original CRT looks to be in order (at least on your video I couldn't see any burn-in, and the phosphor seems to be still quite bright), you don't need to throw it away just because of the cataracts. You can remove the safety glass to sort it out. The chances that you will blow the tube are relatively small (1 in 5?) if you heat it slowly and uniformly and, in any case, better than throwing away the original tube. Red also clearly isn't the original color of the case, as one can see the original light blue showing where the red has pealed off, so I'd surely try very light, low-pressure sand-blasting to remove the after-market layer and then respray with the original color. The keys may also deserve some retrobrighting and UV-protection. Anti-corrosion treatment of ICs and port connectors (with electronics detergent and something like DeoxIT D5) will also help preserve them. And so on. Keep in mind that those machines were never designed to be turned on 50 years later, even in the best case scenarios! But I don't mean that you absolutely have to do all this stuff (although, if you can and feel like it, it's definitely a good idea), the intent is just to give you examples. Keep up the excellent work and thanks for the great content!
Thanks yes no worries. I watched some of your videos and generally was impressed with your thoroughness. The issue with me is I often do things and don't video or don't remember to video/explain. Part of the youtube learning process. In this case, doing my visual, DMM and scope inspections just didn't work with the camera, I kept getting in the way. I probably should be more forceful in saying 'hey, I did this off camera, don't try this at home without doing a b and c', but I forget sometimes, or I feel like there's debate on what proper procedure is and don't feel confident to say 'you must do this'. I've been collecting about 20 years and I've developed an appropriate level of caution. In the old days I would have just plugged something in and most times got away with it but sometimes didn't. These days I trust nothing, I check the wiring out under good light, I look for cold solder joints, breaks, signs of fire, leaks. I always test power supplies as thoroughly as I can both to preserve the equipment and also for safety reasons. For this ADM-1 I did all that, and I had spoken with the seller who insisted it had been powered on without incident before. After verifying there were no issues with power going to the board and that the CRT seemed alright, I decided some short attempts to start it were okay. That said, it will undergo a deeper restoration including hopefully figuring out how to get the implosion shield safely off to clean and remove the cataracts. But for now I just wanted to show folks something that you don't see every day on RUclips. Anyway I appreciate your comment, it did make me think.
I can't believe you haven't bent two paper clips to remove keys yet lol. I don't buy the tool either but some key caps get really stuck on there.
Never thought of that! Sometimes if I can get a couple off I can carefully use my chip puller when they're really stuck on there. But usually with enough pressure I can do it without any tools.
That's a terminal from Fallout
its so pretty o.o
That looks haunted
Good grief if I see another seller say something "powers on" I'm going to jump through the internet and eat their limbs.
You DON'T plug in electronics with unknown provenance. It can and will destroy them in short order, even if it seems to "power on".
Especially valve era stuff, but it'll very likely happen to digital stuff too once all the caps go completely bad.
Well the Eve Computer can sing and dance. Plus I has a hit TV show. Megazone 23
This thing is really interesting, but it has some very serious problems. I think you are going to have to go thru the main logic board one chip at a time, not to mention the video circuits.
i thought the tube was full of algae lol
I would get rid of the red and restore to the original color
11:57 This shot borders on the pornographic
Fun video. Quick suggestion, you may want to balance your audio a bit more. Your voice over is significantly lower than the rest of the audio. So when you switch from your soothing baritone voice to a movie insert or live recording it's a bit shocking.
Thank you. Yes, as a novice my 'skills' with audio have been evolving and sometimes things that sound right to me don't sound quite right to others. Never thought audio would be as hard as it is. Bugger of it is I adjusted the volume downwards are the segments that jump out several times and thought it was under control. Although I did pick a movie sequence where the character kind of raises his voice abruptly.
12:03 That's what she said
Ms saldana north side high school yearling
In moderlur asap yearling high school early grad port
Boy that's one crusty looking machine
send that Tube to shango066 he will get it fixed