I built this version from the RE article using wire wrap on perfboard! I also built all of the add-ons the same way. Eventually I changed the timing using a MM5321 NTSC sync generator circuit and was able to gen lock it to external video. I also built another device, I'm not sure where I got the schematic, that used the same 2513 character generator that displayed a clock in larger font at the top of the text from the TVT. I had the text scrolling and it was used for years as part of a closed circuit channel for a patient information channel in the hospital where I worked. We had B&W TV's in the patient rooms and many of them ended up with screen burn showing 88:88 on the screen where the clock was displayed. I ended up interfacing it with a tone decoder board that controlled some VCR's and it became the entire control and display mechanism for an automated patient educational channel on our MATV system. Nowadays, you could do the whole thing with a Raspberry Pi and some additional storage! Great fun and I learned a lot about chips and TV timing from it.
The clock on your TV was from the September 1974 issue of RE, again written by Don Lancaster. I kept the projects after we went to cable and recently pulled it out and it still works! I built it on Vector board in a card cage with multiple cards for each function. The power supply is actually a surplus power supply from a Control Data CRT terminal. I worked for them from about 1969 to 1974 when I went to work for the hospital.
I built one in about 1977 from scratch. The engineers at my job collaborated to make a run of PCBs from the images in the article, using the company's in-house fab shop. I made all the mods: computer cursor control, a literal bell ("BEL"), variable baud rate, lower case, video ram 7 (or even 8) bits wide. I bent up an aluminum case in the prototype shop, with external keyboard in another aluminum case.
I really appreciate the historical context/background information! Showing vintage hardware is entertaining, certainly, but it is more meaningful when we know _why_ this piece of hardware is important. Imagine a museum without any captions describing the various artifacts on display -- it is fun to look at "old stuff", but largely meaningless to the non-expert.
Thanks for the trip down memory lane. I vaguely remember playing Star Trek on the university computers back in '74-'75 using IBM selectric teletype terminals. There were recycle boxes with reams of continuous fold paper where students work-in-process programs and data dumps ended. We would turn the paper over and print the game play on the other side.
Just encountered this channel and I want to thank you for the deep dive into this bit of history. Many of the names and products you discuss were sold by the computer store I worked at during the late 70's and 80's. I know it's too late to redo the video, but Ed Colle's name was pronounced like Old King Cole, as one syllable. I knew him during that era. He was an independent engineer and worked with a large number of industries, including using a variant of the CT-1024 as the controller for programmable message signs, and a more limited version for gas station price displays. He had a long and varied career from defense communications to beer dispensers, and few of his kind remain.
Dang it! I ran the name by a few people and also found it in a list of names with a recording of its supposed pronunciation. I thought it might be pronounced Cole but I couldn't find anyone to confirm it one way or another. Thanks for correcting that. It must have been really interesting working in a computer store during that time! I hear Daniel Meyer was very strict with his credit terms. :)
Thank you for this video. I was a teenage electronics hobbyist at the time, and read Radio Electronics -- remembering seeing these articles when they came out! I've never seen the kits, so your videos are the next best thing. One suggestion, please -- my hearing isn't the best, and find the background music interferes with your expert commentary. Maybe mix down the music, or eliminate it. Thank you again, I'm bingwatching your SWTC videos!
Many thanks for watching and glad it brought back some happy memories! And yes, I've learned a fair bit on background music since this video.. I *think* I'm getting it together.
I'm glad I found your channel. I hope it grows and grows. Definitely subscribed now. This is the history of home computing we need, not "Well, Apple released the Apple II and then the Macintosh and here we are today."
Many thanks! I'm still mastering things like audio, but I'm hoping the basic message is getting through ok. I've enjoyed learning about these machines as I collect them and like to share what I learn. There's some really interesting stories to be told out there.
@@TechTimeTraveller One thing I would suggest is that when you are doing your b-roll to voiceover later, you don't have to gesticulate like you're doing "live" audio over it (unless you in fact, are). Other than that, these are really sharp vids!
I purchased a CT-1024 kit in 1976 when I was 14 years old with the intrigue of wanting to display characters on a TV screen prompted by the Radio Electronics article for the original TV-Typewriter I had seen when I was about 10 years old -- what fun to build that kit then later make mods for it to display 64 characters per line. I did not know anything about computers at that time, but was fascinated by the SWTPC 6800 computer featured in their catalog. The description of 6800 instructions was alien technology. The cost for the computer kit a bit prohibitive ($395 as I recall). A friend clued me in on building a modem kit (~ $130) which connected me to school timeshare computer and I learned BASIC, then on from there learned about wire wrapping and building home brew computers and learned machine language programming. A key element too was being clued in on availability of IC data books, most often for free, which augmented the descriptions provided in kit instructions. A few years later I traded my CT-1024 and my first home-brew Z-80 computer for 16K of DRAM for my (then new) Apple II. I regret that a bit, but that memory would serve me well.
12:33 - SWTPC is the only company I know of that used (large) Molex connectors for anything *other* than power! Even their audio *preamp* also featured such a motherboard bus structure! I've had more than one experience where there'd be open connections even while fully inserted! I'm guessing a lot of the problems stemmed from that choice of connector.
Generally I've found my SS50 gear to be pretty reliable, but the pins are an absolute nightmare when you're trying to just gently remove a card. They bind horribly.
Ironically, SWTCP went to the Molex connectors for the very reason that the S-100 bus used by Altair, with it's smaller, close-spaced pins, was considered by many to be unreliable. The belief was, that the Molex pins made a more solid connection and the pins couldn't short together. I built the SWTCP 6800 and all of the associated kits in 1976, and one reason I decided on SWTCP is because articles about the 50 pin bus convinced me that it was less prone to failure. It is very hard to remove boards from the original 6800 computer, but I don't recall that I have ever had a bus related problem. I still have the computer, terminal and cassette interface, and the last time I turned it on (5 years ago) everything still worked perfectly.
Love old vintage tech like this. I have an old keyboard that looks like the one that is part of the terminal in the metal box. I was going to use it with a Micro Mint terminal board as part of an S-100 system but I never got around to putting the units together. You could turn on local echo in Hyper Terminal after you type L so you could watch the data being sent to the SWPTC.
Great video! I love looking back at the history of this stuff, and especially how you take the time to explain everything in great detail. Thank you. Also, I realize this is only tangentially related to the context of homebrew and home micros, but speaking of documentation; Northern Telecom (Nortel) / Bell Northern Research is known for theirs, and is considered by many to be "best practices" when it comes to developing technical documentation. AT&T and The Bell System used NT's style guides to layout all their internal documentation, also called BSPs or "Bell System Practices", and later would go on to use them for consumer guides as well. Mitel, Aastra, Lucent Technologies, and AT&T Consumer Products continue to use them to this day.
I'd guess that the "squiggly" cursor is a dried-out timing capacitor. It's flashing as fast as the character generator is clocking. Would also explain why it starts to destabilize the video too. Neat widget though. I can see why this was a huge deal, even though I didn't come onto the scene until a decade later.
The fact that if you just couldn't get something working and couldn't figure out the problem that you could send it in is SUCH a huge boon in my eyes. It dramatically raises the confidence of novices who would love to build one of these but it would be their biggest project yet and they're not sure they're up to the task yet. If your time and effort just wasn't enough, you could save up and eventually get it working for a little more. That had to have increased sales and interest.
I would wonder if one of the keys that seems to stop output is actually a line mode vs interactive mode switch. Especially on slow dialup connections, being able to edit the line you are working on and then sending a complete line when you hit enter could be helpful as it does take time for every character crossing through the serial interface, and sending 30-40 characters w/o included backspaces, and courser movements was handy at times. The fact that some of the TVT boxes include the ability to capture input, and then send it back with a single button press, suggests that a line mode might have been made available.
Great video! I really like all the extensive research you did, and I definitely learned a lot from watching this. Someday, maybe in my dreams, I'll find one of these and a PET for my collection! Ha!
I absolutely loove these videos. I's a bit "before my time" as being from 1974 and "enrolled" a bit later into Philips G7400 Videopack and then the whole C65/amiga/PC scene. It's all about understand what shoulders you "stand on".
Really neat piece of kit. Still, 110 baud sure is... something. Wow. Makes 300 baud look like DSL in comparison (which is admittedly entirely reasonable, seeing as that is nearly 3x faster), let alone 1200.
Don't forget that cabinetry options were thin with only a limited selection of boxes and panels widely available. As a result you'll find a lot of strange uses of wood in addition to just leaving the guts hanging bare. If corrugated sheet plastic had been widely available it probably would have seen use too.
CTRL-G (aka Bell) is still supported on all *NIX type machines eg Linux, BSD, Mac etc. Its often used as an error noise. Having said all that, with an appropriate interface you can control all of those machines from a serial terminal!
I don't know if I can speak for the 1970's kit builders, but project enclosures are a pain in ass! Off-the-shelf ones are expensive, difficult to source, even today, and never quite right. Having one custom-built is prohibitively expensive. Also, I believe sheet-metal and/or woodworking tools/skills are in short supply among electronics nerds.
I was a kid back then and poor AND in England but I would have loved to have been "in on this" it really would have been, like Kraftwerk said... "beam myself into the future".
I recall a Radio Shack parallel keyboard from the same era. Built it hoping to add on the terminal part. Just had the TV typewriter cookbook and didn't quite understand the "divide by" blocks in it. I was in middle school at the time..
Thanks for the detailed overview. Regarding your overheating 6800, might be worth swapping out the 5V regulators on the computer boards to more efficient modern replacements that use less power.
@@TechTimeTraveller Frankly I surprised myself that I remembered this -- I first learned the keyboard codes ca. 1983 when I was learning BASIC programming. 😀
Great video! I just recently found your channel and immediately subscribed! A question, what are all the wires connected to the boards, like the cursor board for example, why are these connections not made through the molex connectors?
Thank you! If I had to guess I would say it was because Southwest wanted to keep the spacing of components such that it would be harder for hobbyists to male accidental solder bridges, and there may have been only so many things they could pass to down to the mainboard without ending up with tightly packed traces and a need to locate some components closer together. Just a guess.
Great video I'd love to hear the story of how you came by the Crawford computer. Also for me the dialogue is too fast. I slowed it down to ~0.85 but loved seeing this.
You improve with every video. Keep up the good work. Maybe less repetitive music in the future; levels were mostly ok but the repeating guitar phrases started to drive me nuts after a while. Also, the hand-waving was distracting because it didn't always match the narration, which turned it into random hand-waving.
Background music is a lot trickier than I ever anticipated. My mistake I think was audition normalizing for -3db, which brought the volume below what it normally is making the background music a lot more noticeable. I didn't catch it until it was too late. Also need to find better music options or go outside the audio library as what they have is mostly short and repetitive. Or they have new age stuff that doesn't sound right at all in a vintage computer video.
@@TechTimeTraveller did you try using the essential mixing panel in audition? One track for voice, one track for music, set both tracks appropriately, do normalize loudness for both tracks, then most importantly: duck the music track to the audio track. If you don't do this, the music is too loud.
Many thanks. Yeah I had some challenges on this one.. was learning Audition and on the last render it did something funny with the levels. Audio has required more of a learning curve but I think the latest video had it dialed in pretty good.
Do they still sell "solder con sockets" ? I want to build a mark-8 as close as I can to someone in the 70's from a magazine but I can't seem to find them.
I think pressing either "0" or "?" in Startrek gives you a list of commands.) My history with Klingon/Startrek was interesting. Our high-school electronics teacher had a TRS-80 model I that we got to use in class mostly -- yeah it was 1977 but our county had like the only high-school electronics program in our state, so thank-you to the fates (and I believe our mother's diligence and research, when we found out we'd be moving to the state) for landing us close to a school-system with that feature -- anyways, the electronics instructor wangled a loan of this brand-new computer with color-and-sound, the Apple II, for a couple of days - and it had Startrek - a very fun experience, which got me obsessed with owning an Apple II (think Wayne's World - "oh yes, it will be mine!") so after graduation, i was working a minimum-wage job, and got a bank-loan with my dad co-signing, and brought home an Apple ][ Plus - with the floating-point Applesoft (really Microsoft) BASIC - wow, right? I went hunting for a copy of Startrek, only to find out that it was written in the older Apple Integer BASIC, which wouldn't load in Applesoft. SO... went to the computer store, and begged them to let me load up Startrek, then print out the code. They were fine with that. Huge printout. Me and my brother, spent like, months, with him reading the printout, and me typing it in, and stopping to troubleshoot whenever I keyed in some Integer BASIC construct that wasn't present in the other BASIC. We became very familiar with the constructs of both languages, and there was a significant amount of re-writing to do. but we did finally get to play Startrek. Only took all the money and time i had. to play one game. Did develop some good chops though, and that machine literally did snag me my first computer-job -- and the rest is hysteria, as they say. Thanks, Startrek!
Did you make new keyboards, key bodies, and key caps? I have a beautiful TVT2 in a formed, smoked plexiglass or Lexan case. I suspect it may be Lexan because I just dropped a ShopSmith jointer on it from about 2ft and all it did was snap off a few key caps. If you didn't make new key bodies and caps, do you have a source for replacements?
No those are the originals. The keycaps were made I think by a long defunct company called Mechanical Enterprises. I've never found an exact replacement. Are your caps totally destroyed? I have had some luck gluing together. Other option is wait for another keyboard to come up for sale.. there's actually one on ebay although the price is a bit out there.
@@TechTimeTraveller Five caps were snapped off at the shaft that comes from the switch body, and they flew to the far corners of my storage unit. I've only found one of them so far. I will try super-gluing them back on when I find them all, but I'm not confident that will last long. It's too bad; mine is the best looking TVT I've ever seen. And all of the ICs were socketed from day one. I saw that eBay one...not happening. Mine is the newer KBD-5 with the 40pin encoder chip, but the keys do look the same. Not the exact same layout though. Responding within minutes to a comment on a 3yr old post = awesome! 👍
There’s this high-pitched ringing in some sections of some of your videos where older TVs and other devices are turned on. I was wondering if in video editing it would be simple to remove the higher-pitched sounds. If not it’s fine, it’s pretty faint and I wouldn’t be surprised if that had already been done; it’s MUCH better than my CRT 😅 I just thought I would let you know.
Yes.. around 15kHz I believe. It is CRT whine and unfortunately at my age I cannot hear it. I have been trying to nail it with filters going forward but of course I have to rely on visual meters since I can't actually hear it for check purposes. On occasion I've had CRTs turned on off camera and didn't realize they were even there and so totally missed the opportunity to filter. Apologies!
I think there was something about that that didn't work.. can't remember why though. I recall setting up that way in some other situation and could see the S records whizzing by. Hmm.. good point.
If Klingon is like other "Trek" games I've seen, it's the self destruct password, if you are surrounded and are going to lose, you can blow up your ship and take out all the Klingons around you, provided that you remember your password.
When you mentioned about making a Retro Keyboard why not use modern MX Cherry switches and use some vintage like keycaps. I know you can find some vintage keycaps for them, I went down that rabbit hole with the DIY Mechanical Keyboard scene.
For me if I'm doing a retro project I tend to want authenticity, even if the original was inferior. I like the challenge of trying to recreate something to that level. It would certainly be easier to use Cherry though and much nicer to type on!
I recently built a version of the www.n4vlf.net/ps2.html Ps2 to ASCII keyboard adapter and it allows you to use a real if somewhat vintage keyboard with this thing. I dragged out my old wire wrapped version and it still works but I don't have the commercial VCR players. When i retired from the hospital they had moved on to cable TV and stopped doing the in-house channel so I retrieved my project and kept it.
It hurts to even think how they did these terminal functions in hardware instead of using a microprocessor. Scrolling must have required a bunch of shift registers to read and write the entire video memory by one line.
@@TechTimeTraveller I've been interested in making a Z80 computer for a while, and have had trouble finding any reliable sources that aren't abandoned projects.
The only time I used 110 baud was with a teletype interface and with a paper tape storage/reader. I think the paper tape machine once could do 150 baud, but it got errors. I used 300, 600, and 1200 with BBS before the more advanced modems were invented.
If its the one that just sold with the metal casing, you'll need a composite monitor and you'll have to find the video out wire going to the original monitor, disconnect and simply add the appropriate connector (usually RCA style phono plug) for your monitor.
@@TechTimeTraveller Yes it is! I guess we both hang out on eBay! I was amused that the seller didn't know what it was. If he did, and he had labeled it correctly, I'll bet he would've gotten more interest in it. He accepted my offer of $200, without the CRT. That also saved me $100 on shipping. That monitor looked like it was more likely to electrocute me, than to display an image. It's good to know that it's just a composite input. Back in the 1970s, composite inputs were rare, and people had to fiddle with RF adapters. Then, in the 80s or 90s, they became common. That'll be easy for me to deal with.
29:48 Given the simplicity of the keyboard and how it works, it wouldn't be difficult to use those keycaps from the original to create your own keyboard. Hell, you could even use microswitches and some wee 3d printed parts to sit between keycap and switch. I've years of electronics experience, though, so I'm not sure if I'm just seeing this from my own position
8:15 not that it needs to but I find it weirdly interesting how even with plausible execution you can quickly tell that the hand gestures don't go with the narration. kinda reminiscent of dubbing in hong kong kungfu movies :)
Yeah the story of that was I did the video as a walk and talk.. but I hated the audio so I went back and did narration.. but kept the original footage and yeah.. rookie mistake. :) got called out a lot on that one when it first came out.
How do you mean? The machine was a terminal so it had to be hooked up to a computer to do anything useful. No way to directly print off it or anything.
@@climbeverest Loopback, what is typed goes out, what is displayed is echoed or sent back by the remote device. a loop allows immediate display of typing.
It would be nice to have a cheap modern TV-Typewriter in a cheap PC keyboard format with serial and VGA output. and there is LILYGO® FabGL VGA32 VGA ESP32 PSRAM Module V1.4 Controller PS/2 Mouse Keyboard Graphics Library Game ANSI/VT Terminal Circuits matchbox size.
Ah, those were the days. Back then computing was real. You had to do something to get something. Nothing comes for free. The recent developments in computing only made the people lazy and ignorant. (yes, I am polite) There is nothing wrong with having to count the number of Bell-signals, lets say to sixty-seven times and then look up in the book of error-codes what error #67 means. All men, whom have been created equal, that still have to think for themselves while computing use more of their brains than others. It is exercising the gray cells, it is a real workout!
Did you know that you can make the same kind of money *without* ads on LBRY? You can even set up LBRY to automatically publish your RUclips videos there, and rake in the dough without doing anything.
@@TechTimeTraveller Yeah, I was listening on my phone and maybe it was just louder there. It was like the voice was at 60% and background music at 40%.
Yes, I have noticed a wide discrepancy from device to device. I try to optimize the audio with headphones. But then you throw a different set on and they have heavy bass or something and I can feel every breath I took going directly into my brain. I will keep trying to find the best common denominator.. it may mean simply giving up background music entirely. I just always liked it for the 'documentary ambience.
Appreciate the feedback. Are you referring just to the segment where I did a voiceover? Or also where I was working 'live' with the machine? The voice over part was originally done live, but I didn't like how long it got so I tightened it up with a voice over and reused the footage. I didn't notice how distracting it was as it was a short piece of a 55 min video. But I will definitely knock that off next time. :)
@@timlocke3159 Yeah, I should have reshot that after deciding to ditch the original audio. In the past I always did voice-over but am trying to a bit more live. That segment just got too long on first recording. Chalk it up to more learning. :)
I built this version from the RE article using wire wrap on perfboard! I also built all of the add-ons the same way. Eventually I changed the timing using a MM5321 NTSC sync generator circuit and was able to gen lock it to external video. I also built another device, I'm not sure where I got the schematic, that used the same 2513 character generator that displayed a clock in larger font at the top of the text from the TVT. I had the text scrolling and it was used for years as part of a closed circuit channel for a patient information channel in the hospital where I worked. We had B&W TV's in the patient rooms and many of them ended up with screen burn showing 88:88 on the screen where the clock was displayed. I ended up interfacing it with a tone decoder board that controlled some VCR's and it became the entire control and display mechanism for an automated patient educational channel on our MATV system. Nowadays, you could do the whole thing with a Raspberry Pi and some additional storage! Great fun and I learned a lot about chips and TV timing from it.
The clock on your TV was from the September 1974 issue of RE, again written by Don Lancaster. I kept the projects after we went to cable and recently pulled it out and it still works! I built it on Vector board in a card cage with multiple cards for each function. The power supply is actually a surplus power supply from a Control Data CRT terminal. I worked for them from about 1969 to 1974 when I went to work for the hospital.
I built one in about 1977 from scratch. The engineers at my job collaborated to make a run of PCBs from the images in the article, using the company's in-house fab shop. I made all the mods: computer cursor control, a literal bell ("BEL"), variable baud rate, lower case, video ram 7 (or even 8) bits wide. I bent up an aluminum case in the prototype shop, with external keyboard in another aluminum case.
you sir are a national treasure
I really appreciate the historical context/background information! Showing vintage hardware is entertaining, certainly, but it is more meaningful when we know _why_ this piece of hardware is important. Imagine a museum without any captions describing the various artifacts on display -- it is fun to look at "old stuff", but largely meaningless to the non-expert.
I used to have a copy of Don Lancaster's book as a kid. I found the ideas in it quite interesting.
Thanks for the trip down memory lane. I vaguely remember playing Star Trek on the university computers back in '74-'75 using IBM selectric teletype terminals. There were recycle boxes with reams of continuous fold paper where students work-in-process programs and data dumps ended. We would turn the paper over and print the game play on the other side.
Just encountered this channel and I want to thank you for the deep dive into this bit of history. Many of the names and products you discuss were sold by the computer store I worked at during the late 70's and 80's.
I know it's too late to redo the video, but Ed Colle's name was pronounced like Old King Cole, as one syllable. I knew him during that era. He was an independent engineer and worked with a large number of industries, including using a variant of the CT-1024 as the controller for programmable message signs, and a more limited version for gas station price displays. He had a long and varied career from defense communications to beer dispensers, and few of his kind remain.
Dang it! I ran the name by a few people and also found it in a list of names with a recording of its supposed pronunciation. I thought it might be pronounced Cole but I couldn't find anyone to confirm it one way or another. Thanks for correcting that. It must have been really interesting working in a computer store during that time! I hear Daniel Meyer was very strict with his credit terms. :)
Thank you for this video. I was a teenage electronics hobbyist at the time, and read Radio Electronics -- remembering seeing these articles when they came out! I've never seen the kits, so your videos are the next best thing. One suggestion, please -- my hearing isn't the best, and find the background music interferes with your expert commentary. Maybe mix down the music, or eliminate it. Thank you again, I'm bingwatching your SWTC videos!
Many thanks for watching and glad it brought back some happy memories! And yes, I've learned a fair bit on background music since this video.. I *think* I'm getting it together.
Another great video! I like that you're kind of spelling out the evolution of the microcomputer one significant advance at a time.
I'm glad I found your channel. I hope it grows and grows. Definitely subscribed now. This is the history of home computing we need, not "Well, Apple released the Apple II and then the Macintosh and here we are today."
Many thanks! I'm still mastering things like audio, but I'm hoping the basic message is getting through ok. I've enjoyed learning about these machines as I collect them and like to share what I learn. There's some really interesting stories to be told out there.
@@TechTimeTraveller One thing I would suggest is that when you are doing your b-roll to voiceover later, you don't have to gesticulate like you're doing "live" audio over it (unless you in fact, are). Other than that, these are really sharp vids!
I purchased a CT-1024 kit in 1976 when I was 14 years old with the intrigue of wanting to display characters on a TV screen prompted by the Radio Electronics article for the original TV-Typewriter I had seen when I was about 10 years old -- what fun to build that kit then later make mods for it to display 64 characters per line. I did not know anything about computers at that time, but was fascinated by the SWTPC 6800 computer featured in their catalog. The description of 6800 instructions was alien technology. The cost for the computer kit a bit prohibitive ($395 as I recall). A friend clued me in on building a modem kit (~ $130) which connected me to school timeshare computer and I learned BASIC, then on from there learned about wire wrapping and building home brew computers and learned machine language programming. A key element too was being clued in on availability of IC data books, most often for free, which augmented the descriptions provided in kit instructions. A few years later I traded my CT-1024 and my first home-brew Z-80 computer for 16K of DRAM for my (then new) Apple II. I regret that a bit, but that memory would serve me well.
12:33 - SWTPC is the only company I know of that used (large) Molex connectors for anything *other* than power! Even their audio *preamp* also featured such a motherboard bus structure!
I've had more than one experience where there'd be open connections even while fully inserted!
I'm guessing a lot of the problems stemmed from that choice of connector.
Generally I've found my SS50 gear to be pretty reliable, but the pins are an absolute nightmare when you're trying to just gently remove a card. They bind horribly.
Ironically, SWTCP went to the Molex connectors for the very reason that the S-100 bus used by Altair, with it's smaller, close-spaced pins, was considered by many to be unreliable. The belief was, that the Molex pins made a more solid connection and the pins couldn't short together. I built the SWTCP 6800 and all of the associated kits in 1976, and one reason I decided on SWTCP is because articles about the 50 pin bus convinced me that it was less prone to failure. It is very hard to remove boards from the original 6800 computer, but I don't recall that I have ever had a bus related problem. I still have the computer, terminal and cassette interface, and the last time I turned it on (5 years ago) everything still worked perfectly.
This is a really well produced video!
Love old vintage tech like this. I have an old keyboard that looks like the one that is part of the terminal in the metal box. I was going to use it with a Micro Mint terminal board as part of an S-100 system but I never got around to putting the units together. You could turn on local echo in Hyper Terminal after you type L so you could watch the data being sent to the SWPTC.
Great video! I love looking back at the history of this stuff, and especially how you take the time to explain everything in great detail. Thank you.
Also, I realize this is only tangentially related to the context of homebrew and home micros, but speaking of documentation; Northern Telecom (Nortel) / Bell Northern Research is known for theirs, and is considered by many to be "best practices" when it comes to developing technical documentation.
AT&T and The Bell System used NT's style guides to layout all their internal documentation, also called BSPs or "Bell System Practices", and later would go on to use them for consumer guides as well. Mitel, Aastra, Lucent Technologies, and AT&T Consumer Products continue to use them to this day.
I'd guess that the "squiggly" cursor is a dried-out timing capacitor. It's flashing as fast as the character generator is clocking. Would also explain why it starts to destabilize the video too. Neat widget though. I can see why this was a huge deal, even though I didn't come onto the scene until a decade later.
You're quickly becoming one of my favorite tech channels, I hope to see more content.
The fact that if you just couldn't get something working and couldn't figure out the problem that you could send it in is SUCH a huge boon in my eyes. It dramatically raises the confidence of novices who would love to build one of these but it would be their biggest project yet and they're not sure they're up to the task yet. If your time and effort just wasn't enough, you could save up and eventually get it working for a little more. That had to have increased sales and interest.
I would wonder if one of the keys that seems to stop output is actually a line mode vs interactive mode switch. Especially on slow dialup connections, being able to edit the line you are working on and then sending a complete line when you hit enter could be helpful as it does take time for every character crossing through the serial interface, and sending 30-40 characters w/o included backspaces, and courser movements was handy at times. The fact that some of the TVT boxes include the ability to capture input, and then send it back with a single button press, suggests that a line mode might have been made available.
Great video! I really like all the extensive research you did, and I definitely learned a lot from watching this. Someday, maybe in my dreams, I'll find one of these and a PET for my collection! Ha!
I absolutely loove these videos. I's a bit "before my time" as being from 1974 and "enrolled" a bit later into Philips G7400 Videopack and then the whole C65/amiga/PC scene. It's all about understand what shoulders you "stand on".
I think the password prompt is to set it for if you want to self destruct you have to enter it to validate you want to destruct.
Really neat piece of kit.
Still, 110 baud sure is... something. Wow. Makes 300 baud look like DSL in comparison (which is admittedly entirely reasonable, seeing as that is nearly 3x faster), let alone 1200.
Seeing your labels on there.... be great if you could get hold of a Dymo and some authentic tapes. ;)
Don't forget that cabinetry options were thin with only a limited selection of boxes and panels widely available. As a result you'll find a lot of strange uses of wood in addition to just leaving the guts hanging bare. If corrugated sheet plastic had been widely available it probably would have seen use too.
CTRL-G (aka Bell) is still supported on all *NIX type machines eg Linux, BSD, Mac etc. Its often used as an error noise. Having said all that, with an appropriate interface you can control all of those machines from a serial terminal!
I don't know if I can speak for the 1970's kit builders, but project enclosures are a pain in ass! Off-the-shelf ones are expensive, difficult to source, even today, and never quite right. Having one custom-built is prohibitively expensive. Also, I believe sheet-metal and/or woodworking tools/skills are in short supply among electronics nerds.
I was a kid back then and poor AND in England but I would have loved to have been "in on this" it really would have been, like Kraftwerk said... "beam myself into the future".
49:20 - Control-G / Bell can be sent from the computer to cause terminal to beep, as a basic sound device.
Thanks for sharing. 😉👌🏻
I recall a Radio Shack parallel keyboard from the same era. Built it hoping to add on the terminal part. Just had the TV typewriter cookbook and didn't quite understand the "divide by" blocks in it. I was in middle school at the time..
This stuff is so incredibly cool. I didn't even have a clue that there was a computer scene back in the 70s. It took me another decade to catch on.
Thanks for the detailed overview. Regarding your overheating 6800, might be worth swapping out the 5V regulators on the computer boards to more efficient modern replacements that use less power.
I can't help but think this inspired Steve Wozniak's design for the Apple I.
26:30 Ctrl-H is backspace (ASCII 8)
Thank you. I couldn't remember it off the top of my head and never got around to figuring it out and editing back in.
@@TechTimeTraveller Frankly I surprised myself that I remembered this -- I first learned the keyboard codes ca. 1983 when I was learning BASIC programming. 😀
Great video! I just recently found your channel and immediately subscribed! A question, what are all the wires connected to the boards, like the cursor board for example, why are these connections not made through the molex connectors?
Thank you! If I had to guess I would say it was because Southwest wanted to keep the spacing of components such that it would be harder for hobbyists to male accidental solder bridges, and there may have been only so many things they could pass to down to the mainboard without ending up with tightly packed traces and a need to locate some components closer together. Just a guess.
These keyboards look like the inspiration for soviet home computers like the zx clones
Great video I'd love to hear the story of how you came by the Crawford computer. Also for me the dialogue is too fast. I slowed it down to ~0.85 but loved seeing this.
You improve with every video. Keep up the good work.
Maybe less repetitive music in the future; levels were mostly ok but the repeating guitar phrases started to drive me nuts after a while. Also, the hand-waving was distracting because it didn't always match the narration, which turned it into random hand-waving.
Background music is a lot trickier than I ever anticipated. My mistake I think was audition normalizing for -3db, which brought the volume below what it normally is making the background music a lot more noticeable. I didn't catch it until it was too late. Also need to find better music options or go outside the audio library as what they have is mostly short and repetitive. Or they have new age stuff that doesn't sound right at all in a vintage computer video.
@@TechTimeTraveller did you try using the essential mixing panel in audition? One track for voice, one track for music, set both tracks appropriately, do normalize loudness for both tracks, then most importantly: duck the music track to the audio track. If you don't do this, the music is too loud.
@@TechTimeTraveller I don't think it's necessary most of the time personally speaking.
I was surprised Adrian Black hadn't seen your SWTP videos. They just throw them away in Seattle.
I spent many hours playing Star Trek on a PET 2001 when I was young and handsome.
Great video. I notice your audio clips a lot, not sure if it's a processing thing or a bad mic. Otherwise, really well done.
Many thanks. Yeah I had some challenges on this one.. was learning Audition and on the last render it did something funny with the levels. Audio has required more of a learning curve but I think the latest video had it dialed in pretty good.
My advice... Replace those labels you put on with period correct dynamo labels as soon as you can. 😁
I keep meaning to look for one on ebay. Got one as a kid from Grand and Toy and I labeled *everything*. :)
Hey I was wondering if you had a foil pattern for the KBD? I actually want to build one. Thanks!
I do but haven't had a chance to scan it yet. I'll make a note to do that asap
Do they still sell "solder con sockets" ? I want to build a mark-8 as close as I can to someone in the 70's from a magazine but I can't seem to find them.
I think pressing either "0" or "?" in Startrek gives you a list of commands.)
My history with Klingon/Startrek was interesting.
Our high-school electronics teacher had a TRS-80 model I that we got to use in class mostly -- yeah it was 1977 but our county had like the only high-school electronics program in our state, so thank-you to the fates (and I believe our mother's diligence and research, when we found out we'd be moving to the state) for landing us close to a school-system with that feature --
anyways, the electronics instructor wangled a loan of this brand-new computer with color-and-sound, the Apple II, for a couple of days - and it had Startrek - a very fun experience, which got me obsessed with owning an Apple II (think Wayne's World - "oh yes, it will be mine!") so after graduation, i was working a minimum-wage job, and got a bank-loan with my dad co-signing, and brought home an Apple ][ Plus - with the floating-point Applesoft (really Microsoft) BASIC - wow, right? I went hunting for a copy of Startrek, only to find out that it was written in the older Apple Integer BASIC, which wouldn't load in Applesoft. SO... went to the computer store, and begged them to let me load up Startrek, then print out the code. They were fine with that. Huge printout. Me and my brother, spent like, months, with him reading the printout, and me typing it in, and stopping to troubleshoot whenever I keyed in some Integer BASIC construct that wasn't present in the other BASIC. We became very familiar with the constructs of both languages, and there was a significant amount of re-writing to do. but we did finally get to play Startrek. Only took all the money and time i had. to play one game.
Did develop some good chops though, and that machine literally did snag me my first computer-job -- and the rest is hysteria, as they say. Thanks, Startrek!
I built one, added a Motorola tv and used it on a Mostek F8 microcomputer board many many moons ago.
Did you make new keyboards, key bodies, and key caps? I have a beautiful TVT2 in a formed, smoked plexiglass or Lexan case. I suspect it may be Lexan because I just dropped a ShopSmith jointer on it from about 2ft and all it did was snap off a few key caps. If you didn't make new key bodies and caps, do you have a source for replacements?
No those are the originals. The keycaps were made I think by a long defunct company called Mechanical Enterprises. I've never found an exact replacement. Are your caps totally destroyed? I have had some luck gluing together. Other option is wait for another keyboard to come up for sale.. there's actually one on ebay although the price is a bit out there.
@@TechTimeTraveller Five caps were snapped off at the shaft that comes from the switch body, and they flew to the far corners of my storage unit. I've only found one of them so far. I will try super-gluing them back on when I find them all, but I'm not confident that will last long. It's too bad; mine is the best looking TVT I've ever seen. And all of the ICs were socketed from day one.
I saw that eBay one...not happening. Mine is the newer KBD-5 with the 40pin encoder chip, but the keys do look the same. Not the exact same layout though.
Responding within minutes to a comment on a 3yr old post = awesome! 👍
There’s this high-pitched ringing in some sections of some of your videos where older TVs and other devices are turned on. I was wondering if in video editing it would be simple to remove the higher-pitched sounds. If not it’s fine, it’s pretty faint and I wouldn’t be surprised if that had already been done; it’s MUCH better than my CRT 😅 I just thought I would let you know.
Yes.. around 15kHz I believe. It is CRT whine and unfortunately at my age I cannot hear it. I have been trying to nail it with filters going forward but of course I have to rely on visual meters since I can't actually hear it for check purposes. On occasion I've had CRTs turned on off camera and didn't realize they were even there and so totally missed the opportunity to filter. Apologies!
34:28 - Couldn't you switch Hyperterminal to echo the data being sent to the computer?
I think there was something about that that didn't work.. can't remember why though. I recall setting up that way in some other situation and could see the S records whizzing by. Hmm.. good point.
If Klingon is like other "Trek" games I've seen, it's the self destruct password, if you are surrounded and are going to lose, you can blow up your ship and take out all the Klingons around you, provided that you remember your password.
That's interesting.. do you get points for that???
@@TechTimeTraveller Honestly, I don't remember how the scoring works
When you mentioned about making a Retro Keyboard why not use modern MX Cherry switches and use some vintage like keycaps. I know you can find some vintage keycaps for them, I went down that rabbit hole with the DIY Mechanical Keyboard scene.
For me if I'm doing a retro project I tend to want authenticity, even if the original was inferior. I like the challenge of trying to recreate something to that level. It would certainly be easier to use Cherry though and much nicer to type on!
I recently built a version of the www.n4vlf.net/ps2.html Ps2 to ASCII keyboard adapter and it allows you to use a real if somewhat vintage keyboard with this thing. I dragged out my old wire wrapped version and it still works but I don't have the commercial VCR players. When i retired from the hospital they had moved on to cable TV and stopped doing the in-house channel so I retrieved my project and kept it.
Oiling the molex pins is a good idea
It hurts to even think how they did these terminal functions in hardware instead of using a microprocessor. Scrolling must have required a bunch of shift registers to read and write the entire video memory by one line.
can you do a video on a Z80 homebrew?
You mean build one for a video? I've thought about that. Have been looking through old magazines for a classic design to try out..
@@TechTimeTraveller I've been interested in making a Z80 computer for a while, and have had trouble finding any reliable sources that aren't abandoned projects.
The only time I used 110 baud was with a teletype interface and with a paper tape storage/reader. I think the paper tape machine once could do 150 baud, but it got errors. I used 300, 600, and 1200 with BBS before the more advanced modems were invented.
I just bought one of these on eBay. What do I need to hook it up to an old TV? Or, what interface should I look for in an old monitor?
If its the one that just sold with the metal casing, you'll need a composite monitor and you'll have to find the video out wire going to the original monitor, disconnect and simply add the appropriate connector (usually RCA style phono plug) for your monitor.
@@TechTimeTraveller Yes it is! I guess we both hang out on eBay!
I was amused that the seller didn't know what it was. If he did, and he had labeled it correctly, I'll bet he would've gotten more interest in it.
He accepted my offer of $200, without the CRT. That also saved me $100 on shipping. That monitor looked like it was more likely to electrocute me, than to display an image.
It's good to know that it's just a composite input. Back in the 1970s, composite inputs were rare, and people had to fiddle with RF adapters. Then, in the 80s or 90s, they became common. That'll be easy for me to deal with.
@@TechTimeTraveller The CT-1024 arrived and it's working fine! But a lot of the keys stick, or don't register at all. Have you found a solution?
Love the video, not so sure about the plinky plonky musak :(
Oh, how I remember and hated those chunky Molex interconnects !
08:50 Aah documentation...
Paper -> disk -> CD -> online.
They really are awful. I'm told hardware hackers loved them for some reason but I really don't get it.
@@TechTimeTraveller They were cheap.
29:48 Given the simplicity of the keyboard and how it works, it wouldn't be difficult to use those keycaps from the original to create your own keyboard. Hell, you could even use microswitches and some wee 3d printed parts to sit between keycap and switch. I've years of electronics experience, though, so I'm not sure if I'm just seeing this from my own position
8:15 not that it needs to but I find it weirdly interesting how even with plausible execution you can quickly tell that the hand gestures don't go with the narration. kinda reminiscent of dubbing in hong kong kungfu movies :)
Yeah the story of that was I did the video as a walk and talk.. but I hated the audio so I went back and did narration.. but kept the original footage and yeah.. rookie mistake. :) got called out a lot on that one when it first came out.
Question, how do you use what you typed?
How do you mean? The machine was a terminal so it had to be hooked up to a computer to do anything useful. No way to directly print off it or anything.
@@TechTimeTraveller tv typewriter implied useful just with keyboard and tv, sorry my mistake
@@climbeverest Loopback, what is typed goes out, what is displayed is echoed or sent back by the remote device. a loop allows immediate display of typing.
It would be nice to have a cheap modern TV-Typewriter in a cheap PC keyboard format with serial and VGA output.
and there is
LILYGO® FabGL VGA32 VGA ESP32 PSRAM Module V1.4 Controller PS/2 Mouse Keyboard Graphics Library Game ANSI/VT Terminal Circuits
matchbox size.
Grandfather of the Rasperry PI's, Arduino's etc...
Not a Star Trek fan? Strike 1
Grew up on commodores? Strike 2
Restored TVTs and shared them? Home run!
Video/PSU capacitors in it are failing which is why the cursor is really fast and the video shakes/wobbles during operation
What is a TV type writer?
11:24 If people were worried about electric shock there would be no murders back then :-P And Edison would perhaps win with hes DC.
Ah, those were the days. Back then computing was real. You had to do something to get something. Nothing comes for free. The recent developments in computing only made the people lazy and ignorant. (yes, I am polite)
There is nothing wrong with having to count the number of Bell-signals, lets say to sixty-seven times and then look up in the book of error-codes what error #67 means. All men, whom have been created equal, that still have to think for themselves while computing use more of their brains than others. It is exercising the gray cells, it is a real workout!
Did you know that you can make the same kind of money *without* ads on LBRY?
You can even set up LBRY to automatically publish your RUclips videos there, and rake in the dough without doing anything.
yu might be responcible for the new wave of zoomers that write their transcripts with tv type writers
Those in the know pronounced SWTPC "swap-tech" ;) Just a little tidbit for ya
I’m liking your videos but man that music is so distracting that I can barely hear you speak
Thank you. Yeah, there is a bit of a learning curve with background music. Are you referring to the guitar at the beginning?
@@TechTimeTraveller Yeah, I was listening on my phone and maybe it was just louder there. It was like the voice was at 60% and background music at 40%.
Yes, I have noticed a wide discrepancy from device to device. I try to optimize the audio with headphones. But then you throw a different set on and they have heavy bass or something and I can feel every breath I took going directly into my brain. I will keep trying to find the best common denominator.. it may mean simply giving up background music entirely. I just always liked it for the 'documentary ambience.
@@TechTimeTraveller Well, don't give up. I'll keep coming back for more content. :-)
Try 3d printing
I find the handwaving distracting.
Appreciate the feedback. Are you referring just to the segment where I did a voiceover? Or also where I was working 'live' with the machine? The voice over part was originally done live, but I didn't like how long it got so I tightened it up with a voice over and reused the footage. I didn't notice how distracting it was as it was a short piece of a 55 min video. But I will definitely knock that off next time. :)
@@TechTimeTraveller The voiceover. It seems forced and out of sync. Some natural hand movement is OK but there is too much there so it is distracting.
@@timlocke3159 Yeah, I should have reshot that after deciding to ditch the original audio. In the past I always did voice-over but am trying to a bit more live. That segment just got too long on first recording. Chalk it up to more learning. :)
PASSWORD = SCREEN LOCK for later
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I am eighth. And we all know ⅛ comes before 1.