I just happened to watch "Kong: Skull Island" and in the first ten minutes they were in a control room and I saw 2 of those DEC VT100 terminals, lol. What a coincidence!

I remember that there was a public domain program available for the Amiga (Fish Disks), that emulated the VT100 terminal. I still have and use a lot of tube type test equipment, and for reforming the caps, I don't bother removing them , and use an isolation transformer, coupled to an auto-transformer to apply the power.. After a physical check, I start applying the power at 30 volts for an hour, and gradually increase the voltage until I am at the operating voltage, I have been using this technique for over 40 years, and have not encountered any problems. For many years, we used the American Airlines computer system for our flight operations (retired pilot), as well as for the reservation system. I thought I might have a an old copy of the manual we used, but I have lost it or tossed it, (although I am notorious for hanging onto things). It was strictly a Unix system, and it didn't matter where we logged in, the flight dispatcher, located in Vancouver, would have all our flight planning documents and weather information printed to our (remote) location anywhere in the world. It was a powerful, flexible, reliable, system. For some administrative functions, I could even log into a part of the system from home.

Very cool!

Adrian I was so excited to see this title!! I first used a Vt100 back in the early 80’s that I also owned. In fact I just purchased a VT101 a few weeks ago that has some problems so that is why I was so excited about this one.

Sharp rectangular soft white rubber drafting erasers work pretty well for keeping the leakage test button down, and they’re squishy to conform well without stressing the button.

The 132 column mode was great for IBM spool output reducing the cost of lineflow paper.

Yes, it’s quite large, but small than the IBM terminals in that time.

Will there be even less adieu now that it will cost even more to import from Canada?

28:00 That ain't dust, something is smoking inside it.

Yep. First step for a beepy non working DEC terminal of any kind was to swap out the keyboard with a known good unit

I don't think the board fixed itself. Either there was some oxidation on one/more of the SIMM sockets, or one/more of the SIMMs wasn't seated the first time around. It wouldn't be the first time I thought all the SIMMs were installed correctly, and re-seating them allowed the board to POST. If you review the footage, it appears as if the gap on the pin 1 side of some of the SIMMs is smaller after you re-seat the SIMMs. Perhaps it is an optical illusion, but perhaps the SIMMs didn't seat right the first time...

VT100! The real deal. Had to use emulators on PC to connect to mainframes but never the real hardware.

if it was non-volatile storage, might it have been Bubble Memory? TI terminals like the Silent 700 used that, and made a big thing out of it as I recall. We had exactly one of these at work, it was dedicated as a console for a Rolm CBX telephone switch

Knowing the 8080A as I do (having built my own tiny "home-brew" computer out of one), that chip to the left and below the 8080 at 8:40 is almost certainly the 8224 clock generator and divider. I'd expect the crystal to be an 18.432MhZ crystal, which the 8224 divides by nine in order to produce the slightly-over 2MhZ clock signals for the 8080. (The 8080 requires two staggered clock signals). The chip to the right of the 8080 is probably the 8228 bus controller which also generates and responds to several signals, including INT, HOLD, and the memory and I/O read and write signals. EDIT: Have a look for two 2114 chips. If they exist on the board, then they provide 1K x 8 bits of RAM, as two 1k x 4 bits chips. They probably provide the stack space and "scratchpad" RAM for the 8080 rather than providing the screen display RAM, since an 80x25 character display would need 2K of RAM. Edit2: You mentioned later that the documentation says it has 3K of RAM, which makes sense. 2K would be for the actual display while the remaining 1K would be the working memory, used by the 8080 for its stack and as a "scratchpad" for data transfer.

You need to let Usagi Electric see that valve based power supply. He'll be over in a shot to help you fix it 😀

All I can say is: I used one back then ... a significant "advancement."

I used them in College on a DEC 20/60 or PDP 11/70

25:50 The handyman's helper: DUCT TAPE

For your vertical deflection issue, check the electrolytic capacitors in the vertical circuit. Those should be easy to check and replace. If my hunch is correct, things will work if those electrolytics are good.

My favorite 'old' terminal from my past. We only had these in the QA and QC departments with Televideo 912c's in the remaining areas of the plant. Luckily I was a backup programmer for QC and got to use that VT100 and it was such a great device to interact with. I miss DEC so much. We later had a number of DEC products which always performed yoeman's duty.

Supported DEC VT100 to VT220 in the mid 80s at my university. Oh the memories! Programming the graphic modes on the VT series was an 'art' form all its own as well.

Recently I took myself back 40 years to my youth by finding a good VT100 font to use with iTerm2 on my Mac.

Oh, excellent! I'm trying to get Uniservo to find me one of these... Perhaps even Commanderscott in Seattle has one still... I LOVE seeing these terminals on your channel! Please, keep this up, Adrian!

Missed you Wednesday!

I worked at an ex-British Rail company in the 1990s and 2000s - they were still using Ventak and ICL terminals in 2006 as a backup method of getting to the mainframe in the event that the LAN/WAN went down. This was connected to the mainframe centres using the "HSDR" or high speed data ring which used the rail network itself as a backbone. These terminals were VT100 compatible of course. I believe the basic systems are still in use - the old HSDR from the 1970s that ran on BR's own telecoms network was adapted into an ATM-based successor called the VHSDR (later MPLS), but the mainframe-based TOPS system is still going, running much of the same old COBOL code. I imagine there will still be the odd ancient terminal still running at a few depots because that old network was virtually unbreakable, and the diesel grease and brake dust in those old huts used to destroy PCs in short order - the terminals just kept going

Memory's fuzzy, but these terminals were capable of being used as monitors for DECs line of desk computers (not desktop, I mean DESK). These were roughly cube-like, about 3-foot cube (1m cube), and had a 8.5" floppy drive. My junior high school had one of these relics, and I played with it some.

In middle school, I went on a field trip to a data center and saw people playing "VT-Trek" on these terminals. Talk about smitten! Those IT people may have been goofing off, but they (and this machine) definitely got at least one young person hooked for a lifetime.

I once had a VT100 that had died. I was a teenager in the very early days of the internet and really did not have the know-how or parts to repair it. My folks wanted me to clear out some of my "junk". I begrudgingly decided to let go of my broken VT100. Imagine my extreme shock when I got to the e-waste section of my small town NH landfill to find a matching unit set neatly to the edge of the pile. I decided it was a sign from some diety above and grabbed it up. It was broken too, but in different ways than mine. Between the two of them I was able to cobble together a perfectly working unit. It worked for years.

I love those old terminals. Later standards introduced simple graphics commands, which were very cool. I once wrote a little ReGIS to SVG converter to replace our old terminals with a web page. (The serial data was sent over a "terminal server" to a linux machine that converted the serial VT340/ReGIS Input to a simple html page with SVG graphics) Fun times :)

40:40 oh don't go jinxing yourself!

They had these in my high school still in use in 1995

Vacuum tube power supply? What is this an Usagi Electric video?!

These could do more than just be terminals. My middle school had a few of these with dual disk drive units on top, running CP/M. The very first computer program I wrote was on mbasic on CP/M on one of these (or perhaps a 101 or 102). In college, we had a ton of these connected to the VAX/VMS system, in multiple buildings (plus VT 220, and more). Being in Massachusetts, the schools had quite a bit of DEC stuff represented. :)

Ah, the history of ROM. With chips you started with mask roms, which were programmed at manufacture and were unable to be changed. Then we got PROM, which allowed you to program once (you could change some bits, but usually only from a 1 to a zero, as programming basically involved blowing "fuses" on the chip). But PROMs were good for prototyping. Then we got EPROMS, which were erasable by exposure to really intense UV light. So they could be programmed, then erased, then programmed again. Then, at long last, we got EEPROMs, which were electrically erasable programmable read only memory. Which allowed you to skip the UV erasure. And on to today, where we have FLASH, which is an EEPROM, but with a better technology. If i missed any steps in this chain, please let me know! I am always down to learn some obscure tech that i haven't heard about. There was some way out stuff in the very early days of computers.

Funny how terminals, which were supposed to just be things you attached to big computers, ended up being computers in their own right. And then, because terminals were a thing, real honestly powerful stand alone computers were used as terminals. Funny old world.

Thinking about it, a second solution is to run the VT-100 video out into a VFS and feed that into a switcher. With the background video source already in time with the house, you would luminance key the VT-100 text over your background video and colorize the text, or shrink or enlarge the text using a DVE. Look up the Quantel 5000+ multichannel DVE. That's what was used back in the '80s.

Adrian, at 28.31 I see smoke comming off the back of the tube ... some thing looks like it is HOT

I’ve worked with DEC’ies throughout my whole career. When I started at Intel in 1998 the factory still ran VAX VMS. Later I worked at HP and many of my of my peers had worked at DEC from the 1970s through the 1990s until Compaq then HP bought them out. Three of my predecessors at my current job worked at Digital in the 1980s in Albuquerque building VT100 terminals.

At 37:40 you mention Time Base Corrector (TBC) (Please note: we are talking B&W video, not color with subcarrier, from the VT100). From your description of splitting the video output to re-time the external input video, a TBC would NOT be used. A Video Frame Synchronizer (VFS) would be used as it would delay the incoming signal up to a frame (a 30th of a second) to bring it into into time with the VT-100. The best solution is to GENLOCK the background source (if it has that input) to the VT-100 video out. Then there is no delay and the source is in time. A TBC is used with a tape deck to synchronize its playout with the facilities' master sync generator. TBCs have a very limited buffer to delay it's video, on the order of 5 to 10 video lines (about 600us). Historically, VFSs replaced TBCs as their price dropped because VFS are more versatile. Now-a-day, a VFS is built into a facility video in processing card to re-time that outside (external) source to the facility (the House). Then all the House video processing cards would be connected to the BDN (Broadcast Data Network) LAN so they are all controlled by one PC on a KVM switch.

You can form electrolytics at low voltages. It won't fully form the cap, but it's usually good enough to get the cap to where you can safely apply voltage to the capacitor in circuit, where it will finish forming. I have formed 600V caps with 24Vdc, and just left it sit for a couple of hours. Worked fine, lasted a long time. ^-^

I've always wanted to get a VT100 and put a RaspberryPI in it to give it some new life!

I was born in May of 81, that thing was probably in transit to a store lol

I haven't used a VT100 since 1991, but here's some stuff I remember: The ANSI/VT100 control codes were not the same as the VT52. While you could put the VT100 into a VT52-compatible mode, in its normal mode the escape sequences were different. For example, on the VT52, the command to position the cursor is ESC Y <row> <column> (row and column values being the actual 7-bit ASCII characters, so to position at row 2, column 1, you'd send ESC Y ^B ^A. Since the VT52 didn't have a 132 column mode, this was never a problem), while in ANSI, it's ESC [ <row> ; <column> H, with row and column sent as numbers. I believe all ANSI ESC sequences start with ESC [ so there is no overlap. The VT100's keyboard was similar to that used in the Kaypro computer (the VT100 had more keys, but it was the same basic layout). Both were made by Cherry. They are mechanical keyboards with physical switches; under each key is two metal leaves that come together when the key is pressed. The stuck keys might be repairable (as I said, it's been a while). Brightness is adjusted using the up/down arrows while in setup mode.

Pretty sure those stickers are for DECword, the main DEC full-screen (sorta) word processor system. I didn't like it, and used RNO (a.k.a. Runoff) instead, which was a text formatter which ran against text files with .dotcommands in the text.

Ahh, tubes. I lvoe tube gear. DO NOT PLUG THAT TUBE METER IN UNTIL IT IS SERVICED! The paper-and-wax capacitors they used 80 years ago like to leak electrically and if you turn it on without replacing every single one of them you will cook tubes out of that thing repeatedly. Burn up transformers. It's not good. A lot of vintage tube desktop radios get murdered this way; unknowing people buy them at antique shops or off eBay, plug them in, 'hey it plays', jam out a bit, and then the magic smoke comes out of them.

I worked at DEC when the VT100 was first introduced, probably around 1978 or 1979. It was the successor to the earlier VT52 terminal, and the VT50 and VT05 which came before. The VT100 was the first terminal to have a detached keyboard, the other 3 designs were one piece. The VT05 was built using standard DEC flip chip modules wired together on a back plane. The VT50 and VT52 were built on a large PCB.

This terminal or a super close model can be seen on a computer chronicles episode during a clip about one of digitals new products. kzbin.info/www/bejne/hnPWfJShorxjnNU 24:27 It seems to be the terminal on the right

Puede pasar. Yo para un proyecto de la facultad arme un cartel electronico de led que funciona por barrido (shiftregisters), esto fue en el 2007. Hoy en dia (2025) muestra los caracteres muchas veces rotos por culpa de los zocalos de las dos memorias (de caracteres y de texto) que no hacen buen contacto. Asi que al quitar y poner las dos memorias el problema se arregla instataneamente, hasta que se deja un par de meses guardados y muestra el mismo problema.

That's the terminal I used in College in the late 1980's. It was connected to a PDP 11/44. I learned BASIC, COBOL and RPG II on it.

The one I was given had the previous owner’s username burned into the phosphors as giant letters comprised of each respective letter.