Despite the risks, I stuck with the black acrylic paint. As long as you let it dry fully, it doesn’t eat the plastic key surrounds. Whew. My painting of the keytops to blue went better — that paint (enamel) doesn’t ‘corrode’ the plastic and can be flaked off. My tiny brush did leave some bubbles behind but it’s ok to look at.
The next challenge was the lettering. Wasn’t sure how Don got his letters on there, although looking at pics on the museum site zoomed in all the way it looked like they were cut from a sheet and then adhered to the key surrounds. Could be dry transfer too (I’ve not touch dry transfers since I was in short pants!)
I decided to try to replicate Don’s work using Avery label stock. However the fonts were a problem. They do have services where you can upload a small jpeg of the font you’re trying to find and it’ll do its best to match it. Unfortunately this particular font was impossible to locate. In the end, I decided to just ‘lift’ the font from the museum photos, photoshop it and then print it.
The next trick was just figuring out what to print it with. I wanted to get the correct ‘sheen’ to match the paint on the surrounds, so initially I thought inkjet + glossy label paper. Nope. Came out way too bright. So then I went laser on non-glossy. Ah. Not perfect, but looked better. I printed basically the image above, used an Xacto to cut away the individual letters and then stuck them on. They look pretty good — the only annoyance was the white edges. I got rid of that using a fine black marker. Result: not bad!
That’s about as far as I can go with the case until I get the boards built. There are still some unanswered questions I think only having the physical boards will answer.
You read that right. After a few days of crisis, debating whether to ‘destroy’ a very difficult to replace original Mohawk keyboard, I finally gave in to my replica demons and resolved to paint. As I stated in the beginning, I wanted the unobtainable. Although I could have left my keytops alone and had something that had the same general look and feel as Don Lancaster’s TVT prototype, the whole point of the challenge was to see how close I could get.
There are all kinds of risks inherent in painting. I believe Don spray painted his legends. Spray painting involves risk — some of the solvents used in these paints can actually damage plastic. Damaging ultra-hard-to get Mohawk keytops would be devastating.
There’s also the problem of matching colours. The flat black Don used ought to be relatively straightforward but the blue was another thing altogether.
And then lastly, how to actually paint them? The square legends and round keytops were a single piece. Try as I might, I could not separate them. So that meant I had to somehow paint the top and bottom separately without intruding on either. And my painting skills are marginal at best. Yike.
I went to Canadian Tire and found my flat black right away, in the automotive section. The cap matched almost exactly what I had in pictures. Perfect. Blue proved trickier, but by a stroke of luck I found a can of Engine enamel in ‘Ford Blue’. And darned if it wasn’t almost exactly what I needed!
The first row of keys would be mostly easy. The first ten keys are completely black. No masking needed.
My spray painting hands did not betray me. The black keys were turning out perfect!
The last key in the row was the red Return key. Fortunately this keyboard came with more than enough red keys for my project, so I’d only have to paint the legends. To mask off the legends, I tried a few different things like masking tape but couldn’t get it to adhere properly for some reason. On one spray test, I found the paint was easily able to get underneath and mark the red key top. Darn!
My next trick was to make a cap out of tin foil and carefully press it around the key.
This more or less did the job with just a tiny bit of overspray creeping up.
While trying to gently remove overspray though I did discover one disturbing thing — the solvents in the black paint actually ate at the plastic keys! The thing I’d feared most! If I didn’t touch them they were fine, and after the paint dried I could actually flake a bit of it off. But if I touched it while still curing, it actually melted and pitted the plastic! Augh! I had to put a couple of keytops aside later because in painting the keytops themselves I accidentally hit the now black legends, and while trying to remove the blue ended up removing some of the black and causing pitting to the legends. Sigh. Oh well.. no going back now!
Here’s a shot with the whole top row and some of the blue done:
And keytop melting aside — I’m getting kind of excited! Now I went for the rest!
The first row of blue keys was easy — they were already blue. The rest of my keys were white, which presented an issue because somehow I had to paint the legends black and then paint the keytops without getting any blue paint on the black. I spent a day thinking about how to mask off the legends but kept drawing blanks. No matter how I thought about it, I ended up with a situation where I could get the correct size hole to poke the keytop through, but the masking material would be so thin and flimsy it would still expose the legend to blue paint anyway. In tests, I also found the blue engine enamel, unlike the black acrylic laquer, didn’t adhere to the plastic very well. In the end, I decided to try hand painting (yike). It wasn’t *that* hard, but I did get some bubbling that I couldn’t get rid of.
Kind of exciting. It’s starting to resemble the original a little bit, at least from a few feet away. 🙂 I have to fix those badly mauled legends on two of the keys, and the bubbling on the blue paint isn’t so hot up close, but, it is a homebrew type thing and plausibly that could have happened to a lesser mortal building something like this back in the heady days of 1973.
I haven’t been posting but I have been doing, sort of.
I wanted to get going and build an externally complete mockup of Don’s TVT prototype, so that I could have it on my desk to inspire and motivate me to keep working at it.
One of the problems with trying to replicate something you have no physical access to is that, the more you research, the more you find out that changes your assumptions. When I got my Mohawk keyboard, I assumed by the keytops and arrangement of keys alone I had the right beast. But looking around online I stumbled across a couple of pics where one of the plastic ‘bezel’ blocks Don used around the periphery of his keyboard (to cover up the workings underneath) had gone missing and the others had slid around. They revealed a metal slotted bracket. This was not the same as the one on my Mohawk, which led me to wonder — did I have the right keyboard?
I needed to find a pic of the so called ‘surplus’ keyboard outside of the TVT unit. Hunting around www.tinaja.com, I discovered this article Don had written detailing his ‘improved ASCII encoder’. Check this out:
Look familiar? This article appeared in 1974 and featured a revised ASCII encoder from the original used in the TVT. For this version, they mounted the encoder beside the keys on the right side. Now, the width of the prototype is known — the museum gave that to me. The keyboard pictured as I said is post-TVT and the encoder Don’s attached to the rails on the right side make it too wide to fit. But the flange looks the same. So what’s up?
As it turns out, the answer is fairly simple. Both mine and Don’s keyboard were ultimately made by the same company: Micro Switch of Freeport, IL. Micro Switch is pretty prolific. I’ve actually got an ebay search followed and have seen tons of their former products go onto market. Micro Switch produced keyboards like ours for Mohawk, Honeywell and others. From what I’ve been able to dig up, it appears Don’s units may have come from decommissioned Honeywell machines – I’ve seen a few with different coloured keys but the same flanges on the sides. My keyboard’s switches date to late 1967, so that kind of explains why they were surplus in 1973.
Now, here’s where I get into a battle with my inner historian. When Don was building his keyboards, these Micro Switch units weren’t rare at all. They were literally being dumped. However, here in 2016 these are a lot rarer. In 7 years of watching around, I’ve only seen mine and one other appear on ebay. Because the legends on mine are white and I only have a handful of blue keys, to get the black and blue coloration Don had, that means I have to paint. And paint, as they say, is forever. Ugh! What to do!
Well, I guess while I have that debate I can at least take it apart. That is reversible, and it’ll let me do a mockup of my unit and figure a few things out about my case design. So.. here we go…
The switches are held in place on their rails by two screws up top. Loosening the screws a little is all it takes to be able to move them. I had to cut the mass of wires shorter to work with it, which was in itself painful but — well, it’s not like they had their original connector at the other end anyway, they were cut at about 2 feet or so. After, I remove several switches to get the number of keys the same as Don’s, then begin to try to rearrange them get the pattern Don had. The basic pattern is already there for the most part. It’s just dropping switches from the right and filling in the blanks with the spacers.
With the pattern figured out, I proceed to test fitment. It appears I will have to router into the left side a bit more deeply than right to compensate for the keyboard having more exposed rail on that side.
I also work to get the plywood top omin place.
Ok.. need to trim this down a little…
Good.. now to cut the opening for keyswitches..
Meh. My routering skills are a bit unpolished. But whatever, it’s a mockup. Alright.. now a bit of glue to see how it goes together:
Not bad. Now to router out the sides for the keyboard and try placing it.
Hey! This thing’s actually starting to look like a TVT.. here’s mine next to my not quite life-size photo of the original:
Now the moral crisis. I’m tempted to ‘leave them keys alone’. You know, authentic recreation rather than replica. But of course, if I’m not going to build an actual replica.. what was the point again?
While internally debating that situation, I decided to hunt down some appropriate vinyl. The vinyl Don used was 1970s faux leather, I think. Finding the exact colour and pattern would be very difficult, since it was probably long discontinued. Further complicating matters, photos play tricks on you. In some photos the vinyl on the prototype looks beige, in others, gold.
I just want to get my mockup built and then do some more photo comparisons. I found some beige-ish vinyl at a Fabricland store in West Vancouver. It looked kind of close. I think Don’s may have been that fake ‘distressed’ leather, although maybe the distress had happened over the course of 40 years. This vinyl is a bit too polished, but that’s okay. Again, it’s just temporary to check things out.
Getting out my ever trusty No More Nails, I began to put the case and rearranged keyboard together. I ended up having to go deep into the left side to get the keyboard centered correctly, and then had to prop it on the right side with a little shelf. Here’s the end result (with a printed pic of the switches to stand in for the real ones for now):
Not bad at all, if I do say so. Okay. Time to sleep on the paint thing and decide if I have the stones to go all the way on this.
Being a ‘TV Typewriter’ and all, it goes without saying that the keyboard is a rather important component of the thing. No matter how well you design the electronics, they’re useless unless you have a physical means to input data. And new keyboards in 1973 were expensive. Unless, of course, you read Radio Electronics for tips on how to get around that problem.
Not that the TVT required an actual keyboard. In the September 1973 Radio Electronics article, Don Lancaster suggested ‘six switches and a pushbutton’ would suffice. Entering letters was a matter of setting the switches and pressing the button. Don claimed with practice decent speed could be achieved, although I think he must have been a pianist to make that arrangement work with any proficiency. Another option was the ‘low cost keyboard’ project offered in the February 1973 issue of RE. Part of Don’s ingenuity was finding extremely affordable ways of doing things; his handmade key switches were crude but brilliant, although you still needed to secure keycaps from somewhere. RE suggested ‘two shot’ moulded plastic keytops made by a company called Mechanical Enterprises of Arlington, Virginia. I have no idea if they still exist. The keytops themselves look pretty close to those found on IBM Selectric typewriters, except for extra functions printed over the letters. You also needed tobuild your own ASCII encoder which would convert the signals generated into letters and numbers that would appear on your screen.
My first order of business in choosing to model Don’s prototype was to find out what kind of keyboard he used. To refresh, here’s what the prototype keyboard looks like:
Link: Computer History Museum, Mountain View, CA
When I asked him about it, his response was that the keyboard was an ‘IBM EBCDIC’ surplus unit. They had taken apart dozens of them and reconfigured into just over 40 complete units that were then offered to TVT builders. I tried to google search using what he had given me but came up short; EBCDIC, which stands for Extended Binary Coded Decimal Interchange Code, like ASCII, was an encoding standard used my several keyboard manufacturers, not a specific model. I asked in forums, on mailing lists. Some claimed familiarity, but could only suggest they were ‘key to tape’ units. One day I got an old school computer hobbyist who remembered something about the TVT prototype using surplus Mohawk ‘key to tape’ keyboards. Again I went to Captain Google, and again he came up short. All I had were photos of the prototype.
I realized I needed a Plan B, because finding anything involving key to tape or punch cards from 1973 today might prove to be impossible. I thought perhaps I could recreate the keytops on the prototype by finding parts that were close and fashioning something that resembled them. The underlying switches wouldn’t matter; they wouldn’t be seen. Since the keytops looked kind of like teletype keys, I did some ebaying around for ‘teletype keys’, and one day came up lucky. A vendor had 62 ‘Repeat’ replacement keys for military teletypes. Apart from every one having ‘REPT’ stamped on it, they looked pretty close to what Don’s prototype had. I figured making them look like the prototype would just be a matter of painting them. So I ordered all of them. Here’s what they looked like:
If you look at the photo of the actual TVT prototype keyboard again, you’ll see these cylinders are set in the lower right corner of black square surrounds that are there to hide the switches underneath. I assumed (incorrectly) that cylindrical keys slid down through the surrounds when pressed. Thanks to my years of model railroading, I had learned how to cast plastic parts using two part resin. I reasoned I could approximate the dimensions of these surrounds, create a mockup of one in styrene, and then make a mould of it and cast it. Then I could adapt the ‘low cost keyboard’ project from the earlier RE article to it, creating a working keyboard that at least had the same exterior look.
I had that all settled up and began making plans, but then one day I had a stroke of luck and ebay coughed up just what I needed. While searching for ‘Mohawk keyboard’, sure enough, one came up. It looked just like this:
From ebay
After close inspection it became very clear this keyboard was what Don had used! The placement and design of the keys were correct, the only difference being colour. Woohoo! This was it: an original Mohawk Data Sciences (MDS) key to tape system keyboard.
My understanding is that key-to-tape was a system that avoided the need to punch data into paper cards. MDS apparently did very well for a time, up until about the late 1970s. I don’t know for sure what happened to them but I imagined it was the same fate as many other proprietary computer brands as the world slowly converged into widely held standards. Many old hands refer to them as ‘IBM Mohawk’, but I see nothing to indicate IBM’s involvement anywhere at the time these key to tape systems were being produced. Perhaps someone can clarify.
My elation at finally locating it was was stopped cold by the asking price, though: a cool $600. I asked around on forums for opinions; even though the price was extremely steep, I reckoned the odds of coming across another unit like this any time soon were slim to none. I was assured that these keyboards were nothing special — just salvage from old Mohawk key to tape units that had once been plentiful. Most said they wouldn’t offer more than $50. I asked the seller if they’d consider offers. They declined, but eventually relisted for $100. I opted to sit out, hoping it would go unsold and be marked down again, but it sold for just over $100. I felt a little bummed — I knew these keyboards didn’t come up every day, and since the sellers themselves didn’t know what they were, searching them out on ebay would require hours of looking up every keyboard in the Vintage Computing section. Who knows when I might see one again? But then a year later, I did! The asking price this time was $100 and I went for it. Here it is:
Mohawk MDS Key to tape keyboard
Interestingly, it’s not exactly the same as the first one I encountered. There are fewer switches up top, and the keys are coloured differently. I’m guessing Mohawk customized these things depending on client and application. Perhaps someone could shed some light on that. The keyboard itself isn’t all that big, maybe about 18 inches wide, but man is it heavy. You know those ‘steelie’ IBM clicky keyboards? They have nothing on this beast. Here’s a few shots around it:
Way cool. There are five screws to remove to get into it, and upon removing the case we are presented with the innards:
The keys themselves sit a good few inches up from the base. Compared to modern keyboards, the space inside is cavernous.
I was surprised to find a speaker in there. I’m assuming that was there to alert to errors and so on. The wire bundle looks pretty intimidating given how many there are. Keeping all that straight looks to be a challenge. In terms of operation, I was expecting a much more mechanical, clunky feel to them as several forum folks had said these key to tape units were a nightmare to type on (I actually found pressing the keys to be relatively smooth, although a bit awkward with the small size and wide spacing). The switches themselves I *think* are faily simple contact switches — two wires each, press it down and the circuit is connected. I’m hoping Don chose these for relative simplicity. I was also wrong about how they operate — when you press on the cylinders, the entire thing, surround included, moves down. The switch mechanism itself below the keytops seem massive for what they are.
You can see in this side profile view the solid blocks installed as spacers. On my keyboard there is a single rectangular ‘LF’ key on the right side. This key does not exist on the first ebay keyboard I came across; rather it is blocked off.
According to Don, he cherry picked blue, red and black keytops from various keyboards for colour, and reassembled them to get the patterns seen in the prototype. Based on what we can see here, it looks like before or after changing/painting keycaps, he removed some keys on the right side and blocked them in, dropped the whole keyboard into his TVT prototype case, and then to center it and hide the metal framing he used to mount it, added a vertical column of blocks on the left side, making it one column wider than it was originally. Neat! I don’t have enough ‘blocks’ to fill in the keys I will have to remove, but those should be easy enough to cast in resin and paint.
To be honest, I’m almost a little hesitant to take this apart. The forum gurus say these units aren’t rare or collectible, but I’ve never seen one myself before and they can’t be that numerous after 40+ years. It’s just a neat thing to look at and appreciate how much keyboards generally have evolved over the years. The thought of painting over the original decaling is perhaps just a bit bothersome to me. I’m sure I’ll get over it, but for now, until we get to the actual construction phase, I’ll enjoy it as is.
One of the challenges with replicating something you’ve never seen in person is getting the details right. In my modelling of the Kettle Valley Railway’s Coquihalla subdivision, I had a problem: the railway didn’t exist anymore. Not the line, scarcely a single building remained. All I had to work with were old photographs and the say so of others. In that situation, you gradually learn to pick out details. How to deduce sizes and distances in photographs using objects with known dimensions. It’s detective work, and quite honestly, I enjoy it.
Now, we’re not quite so far gone with the TVT prototype. The real thing does still exist. I could, if I wanted to, go and see it; however it’s a 2 day drive in another country. And I just don’t have time. Now, fortunately, the prototype’s current owner is the Computer History Museum in Mountain View, California. And they are nothing if not thorough in their catalog of their collection. They had record of the rough dimensions, and had some great frontal and overhead shots. Further, I was fortunate to get in touch with Dag and Chris from the museum, who were very helpful in providing some critical photographs, like this one of the back of the TVT unit, an angle no other photographer bothered with:
I knew the case was made of wood, but that sliver of silver at the bottom of this picture shows was appears to be metal. Which would make sense, since that’s what my TVT2’s motherboard is mounted to. I’m not sure what the screws at the back are holding up; because the case is screwed shut and the museum understandably doesn’t want to risk damage taking it apart, that’ll probably remain a mystery for the forseeable future.
Here’s a kind of side shot Dag was kind enough to send:
It’s hard to say for sure with just pictures, but I’m thinking the wood is probably hardwood — maybe fir or oak. Could be pine too but it looks too dense. I don’t see any screws attaching that wood support in the front to the sides. It appears Don routed into the side pieces wood and then secured the front ‘beam’ with either screws that are hidden inside or maybe glue. Probably I’ll go with No More Nails or something like that with maybe a couple of inside screws. Is the front a 2×4?
I asked Dag if the measurements on the museum’s website were fairly accurate, and he went above and beyond and got another museum staffer to measure the unit again, particularly the wood sides. It turned out that the dimensions were pretty correct, the side wood being 4.25″ high by .75″ thick, the length of the side pieces being 13.125″ at the bottom and 12″ at the top (Don cut the ends on an angle) the entire unit being about 11.75″ wide. Perfect! Now I was ready to cut wood. I got my hands on some 1×5″ fir, which actually measures 1×4.5″. I’ll trim off .25″ inches and then cut to length, and then cut my angles.
Nice! Now I have something tangible!
Now, I know the width is 11.75″. So factoring in for routing on each side, I figured the pieces on either side of the keyboard needed to be about 11 inches. I felt pretty confident they were 2x4s, and I had some 2×4 cedar around. Now I had this:
Cool! But… it doesn’t look quite right. The 2x4s just seem a bit too big. Looking at how much space is left in the back, there doesn’t seem like there’s enough room to fit the TVT boards in there. Drat. Something’s wrong. I need to figure out how big those front and middle pieces are.
Aha! An idea. A trick I learned from using air photos and a large format printer to very precisely model a segment of railway.
First, I took the above shot the museum had. It appeared to be more or less directly over top. I then print screened and copied into Photoshop, cropped it, and then set the image size to the known length and width dimensions. From there, I printed it at that exact size to my Designjet 450c. Voila!
A (roughly) life size printout of the TVT prototype.
I then took out my MDS keyboard and checked the measurements. The keytops are .75″x.75″. Sure enough, my large photo also measured the same. Great. I can trust it. Now I measured those two wood pieces. They come out at just over 1″. So I’m guessing these are 1″x4″, not 2″x4″. That’s going to necessitate a trip back to Home Depot, but at least I know now before I go and router some rather expensive wood ($28.00 for 8 feet).
As mentioned previously, the TV Typewriter was a true do-it-yourself project. Literally all you needed to do to get going was order the plans. The plans listed the parts and included the artwork to make your own PCBs. Now, you didn’t have to go quite that far — Radio Electronics did offer some ‘legs up’. They arranged for SWTPC to manufacture the boards in limited quantity. Don Lancaster and his crew also built about 40 or so ‘surplus keyboards’ to be sold to hobbyists who didn’t want to make or hunt down their own.
Obviously I would have loved to have ‘original’ SWTPC-made boards to work with. Would have saved a lot of trouble. But in 2016, these are a little bit hard to come by. In fact, I’d never seen them for sale ever on eBay or anywhere else. And I assumed if I did come across them they’d be assembled already and ridiculously expensive. I didn’t even bother setting up a ‘followed search’ on ebay for them, so convinced I was that they’d never be available.
And that’s okay. The great thing about the TVT is, as I said, it’s entirely legit to make your own boards. And that’s the thing I think that separates this project from say, an Apple I replica. The latter will always be just that much more ‘replica’ because the original boards only came from Steve & Steve.
Anyway, regarding original SWTPC boards, I was wrong on all counts. I don’t know how, but I completely missed an auction on ebay that offered a complete board set, untouched. The price it went for? A heartbreaking $39.00USD. Ugh. The auction has long since passed but I did manage to save some photos before it went offline:
Now, I suppose this is a blessing in disguise – had I managed to steal those boards, I would have faced a moral crisis about trying to assemble them, since there can’t be that many unassembled TVT boards lying around out there. There was also the risk of assembly damage. Evidently the marketplace did not consider these to be incredibly valuable, but for me they would be irreplaceable. Wrecking them would be an offence punishable by flogging.
On the plus side, at least I now had a visual of what ‘original’ TVT boards looked like. Color, texture, size. From talking to Don, SWTPC’s involvement apparently was a while after the prototype debuted, so probably the prototype boards did not have the SWTPC logos. But otherwise looking at photos of the prototype and the alignment of screws, switches, etc, it’s clear the prototype boards basically were the same. Another useful bit of information – the silkscreening on the back looks more or less the same as the ‘parts placement’ templates in the plans:
That opens up the possibility that I could use toner transfer or some DIY silkscreening method to take the parts placement diagrams and transfer them to the backs of the PCBs I’m making.
The other interesting thing to note with these is they weren’t tinplated. That kind of had me wondering about their authenticity but after consulting with ‘experts’ it appears these ought to be legit — after all, this was quite early in SWTPC’s adventures in computing.
I’ve got my eBay followed searches better tuned now but I know I’ll never see these again. Oh well, another lesson in not making assumptions!
Well first, I had to decide what I was going for. The TV Typewriter was a DIY project; as DIY as you wanted it to be. You could order pre-fabbed boards, but on most of the rest you were on your own. If you really wanted to go all the way, you could take the foil patterns from the construction booklet Radio Electronics offered and make your own boards from scratch. Thus, a TVT, unlike, say, a Commodore PET could literally take any physical form. It wouldn’t therefore be ‘inauthentic’ to just jury rig something together of my own design, as long as it conformed with what a hobbyist of the day would have done.
Trouble was, I really wanted what I created to resemble one of the units pictured in the original RE article. As a collector, the real motivation here was to have something I could not ever buy. There were two units featured in the article: the unit that appeared on the cover, and the prototype Don Lancaster originally built that was pictured in the body of the article. The cover unit had a more refined look, having a proper-looking keyboard, nice decals, etc. I have experience with modelling and part fabrication from my model railroading hobby and, having chosen to model a long defunct railway, am used to doing detective work and recreating things from photos. Plus, nobody seems to know where the cover unit is. It, unlike the prototype, seems to have disappeared into the mists of time. I’d be raising it from the grave, so to speak.
The problem with the cover unit is the keyboard — the underlying switches and electronics were a previous RE DIY project, so those could potentially be recreated. But the keycaps themselves were a limited offer deal that RE pointed readers to. Those are long gone. Perhaps I could get away with some generic grey keycaps, say from an IBM Selectric. But they wouldn’t be ‘correct’, and being that I wanted to create a replica, that would bother me. I wouldn’t have a clue how to have those keytops reproduced. I wouldn’t want to know what it would cost, either.
So then there’s the original prototype. Outwardly this would appear to be easier, from an external visual point of view. Everything is simple; the sides look to be just 1×6″ lumber, the case structure probably some 2×4″s, plywood and the like. The covering is still-available upholsterer’s vinyl. Switches are switches. The keyboard was of a type I’d never seen before, but I had hints that it was related to teletypes or something like that, with those awful cylindrical keys and what looked like square plastic surrounds. The lettering for them appeared to have been printed, cut out, and stuck on the surrounds. This was, I felt, was within my ability to recreate, if I couldn’t find what Don had actually used.
Of course, there’s the matter of the internals. And those are kind of important, because, after all, that’s what this project is all about. I’m fairly confident the internals of the cover display unit, if there were any, probably conformed to the kit design being offered in the article. But the prototype — as the word ‘prototype’ would imply, was a one-off, and that meant the boards inside could be entirely unique, as prototypes usually are. Now, I was fortunate that Don Lancaster is still kicking about and willing to answer questions from the public. But some details are lost to time. There are pictures of the assembled boards and ICs in the article, but the article doesn’t make clear whether these were from the prototype or ‘production’ pieces. The prototype unit is in the possession of the Computer History Museum in Mountain View, California, and they are willing to help me out for research purposes, but they can’t, for obvious reasons, go taking the unit apart to satisfy my curiosity. So it looks like I’m going to have to accept some guesswork there. I’d have to do it regardless of whether I chose the cover unit or prototype.
In the end, I’m choosing to replicate the prototype. One thing about it is the The-Hardware-Store-Guy-Gave-Me-A-Weird-Look exterior design. While the RE cover unit is more put-together and slick looking, I think reproducing the exterior details are probably beyond my abilities for now. The prototype just seems to have the right look for the early 1970s and is more easily within the realm of possibility for me to recreate. I can always try to acquire an extra set of ICs and parts to try building a cover unit replica down the road when I have a bit more experience. So prototype it is. Now to start assembling parts and get going!
Don Lancaster’s TV Typewriter prototype, courtesy of the Computer History Museum, Mountain View, CA.
I’ve been an old computer collector for as long as I can remember. Even before they were old, they were unique – unique in look, unique in personality, unique in how they operated. In the early 1990s as it became clear the world was converging around the PC standard and computers were destined to become generic beige (later black) boxes; that and a little bit of nostalgia for my misspent youth prompted me to seek a few tokens of a disappearing age. In high school I remember the retirement of my school business office’s Commodore PETs, and asking if I might buy one. The PET had been the very first computer I had ever interacted with, as a Grade 1 student. It had been the computer I begged Santa for one Christmas (he responded with a VIC-20).
Anyway, back at the school, a teacher was piqued by my interest in those old Commodores, and was kind enough to secure one for me, free, fantastically enough. A SuperPET, with 8050 drive! A hobby (or more accurately: addiction) was born. I felt like that enthralled 6 year old again. Finally, a PET was mine!
For a good chunk of my early collecting days I had no idea what was really out there. Having been born in the mid-70s, I completely missed some of the earliest experimenting in home computing. My world was Atari, Commodore, IBM and so on.
That world was expanded considerably when the world wide web, and particularly Ebay came along. For the first time I found out that Commodore had produced something other than the PET, VIC-20, 64 and Amiga. I learned to my amazement of the TED series of machines, the C16 and Plus/4. The more I learned the more I wanted to learn. Collecting was made (relatively) easy by Ebay; you didn’t have to chance upon this stuff at a flea market or luck out at an estate sale. You just had to plug in the name of what you were looking for and, poof, there it was (or wasn’t)! It became a hobby in itself to learn about a new system and see if it was available for sale there.
But I digress.
Like I said, my world was the mainstream 8-bit stuff, like Commodore. Apple 1? What’s that? Mark-8? Is that a car? Altair? Never heard of her. I knew nothing of these and countless other efforts by early computing pioneers to break into the impenetrable fortress known as the Home.
Not that computers weren’t available if you really wanted one back then. They were just really expensive and of course the further back in time you go, the bigger a (ware)house you needed. In the early-to-mid 70s, most people had no practical use for a home computer. If they needed to do research, they picked up a book. If they needed entertainment, they hit the theatre. If they needed to type an essay, they had the trusty typewriter.
Some eager engineers had tried and failed (hard) to persuade people of the computer’s usefulness in the home – Honeywell with their hilarious Kitchen Computer springs to mind. Because you know, girls just wanna have fun (programming recipes in octal).
Between that apathy and the phenomenal cost of hardware, there seemed little chance for home computing. Enter Don Lancaster.
Cover of Radio Electronics September 1973 issue, featuring the TV Typewriter project (link: Matt Holley’s SWTPC.COM)
Don Lancaster was a talented engineer working for Goodyear Aerospace in the early 70s. He designed — not a computer, per se, but a thing he called a ‘TV Typewriter’. Don realized that one didn’t need to go out and purchase an ultra expensive video monitor to put text onscreen – in fact, most houses already had a monitor of sorts: their TV. The TV Typewriter would make use of what was already there and open the door to a flood of possibilities: “A super sales promoter! A calculator! A 32 register, 16 place serial computer!” Few of these would actually be realized, but the concept was critical in laying down the foundations of the 8 bit home computing revolution.
It didn’t have a CPU and could not be programmed. It couldn’t even allow you to do basic addition and subtraction like a calculator. Basically, it did exactly (and barely) what was advertised – it let you type stuff on your TV.
It was not a project for the faint of heart – although not nearly as expensive as a proper terminal of the day, it still cost some money and required some serious electronics assembly skills. Don’s prototype was a bargain basement as you got: a wood case covered in upholstery vinyl and a ‘surplus’ keyboard from a key-to-tape machine rejiggered for his purposes. The whole thing had a distinctly homespun feel. I soon realized, I had to have one!
But it was not to be. After years of searching I realized that with fewer than a couple hundred ‘kits’ sent out in total (Southwest Technical Products, an early computing pioneer, partnered with RE and offered a set of pre-fabbed boards the hobbyist could build a TVT from), many unsuccessfully built and likely tossed in the garbage (not to mentiom the passage of 40 years), there was little chance of my finding one online. The closest I ever got was a still pretty rare TV Typewriter II, which was a later design by Ed Colle that was a bit more packaged than the original. I’m really proud of that piece and look at it often, even though it no longer works correctly. (Update: it has been repaired!)
Digression again. So yeah, after concluding I would never likely come across an actual vintage ‘TV Typewriter’ in the wild, I realized, hey, I can do it myself! After all, that’s how it was done back in the day. And thus began my quest to create, from scratch, a recreation of the TV Typewriter. And since I’m recreating, why not make a replica of the original prototype? That would definitely attract some attention at vintage computing festivals!
I knew I would be able to find many of the correct vintage chips, some even period correct, with enough looking online. The boards could be recreated using copies of the artwork originally produced in the construction details booklet RE provided to readers for a fee. I fell in love with the whole idea the more I thought about this potential project – both as a means to acquire something that cannot be acquired, but also to go back in time, into the world of the early computing hobbyist and learn and invent just as they did. Even if I never got the thing to function (and that’s a strong probability; I’m a computer guy but I’m no engineer), at least I’d have it in my collection to show off. And anyway, lots of TVT builders in the day failed too. Failure is just as authentic as success!
The blog that follows will chronicle my efforts to build a ‘new’ TVT, a replica based on Don Lancaster’s original prototype. Get ready to giggle. This computer guy is about to get old-schooled.
