The Most Beautiful Digital Display I've Ever Seen!!!
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- เผยแพร่เมื่อ 15 ส.ค. 2021
- I give you the amazing Sharp Compet 18 calculator from 1969(ish) and it happens to have a set of 12 gorgeous display tubes that I wish would have been around for a lot longer. Where did we stray off the path of beautiful into 7-segment boxes? I wonder.....
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The first calculation result was correct, you pressed the M+ twice
Yeah, I noticed she must have forgotten when she pointed out the place holder pointers. And pressed it again.
Yeah, original entry at 1:59, second entry at 2:19 - interesting that it didn’t update the display, unless that’s supposed to be a “last transaction” type space rather than just “what’s in memory”
@@randombloke82 the memory plus not minus update the display… not even in windows calculator program… it is a buffer addition. The data in storage memory is updated. The display only updates when memory recall is pressed.
I saw tha as well.
I really appreciate that your tear-downs aren’t hack-aparts where a cool old thing ends up broken apart and in a dumpster. Thank you for your care and patience.
Yeah! I had a programable calculator as a Kid, that was HUUUUUUGE, stuffed tightly with over 30 pcb's inside. Don't remember much about it other than that my mom threw it away in her usual rage-fits, where a ton of retro stuff ended up.
@@AmstradExin noooo
The red stamp reads 松田 Matsuda (as in Mazda the car maker who used another spelling); it's a common Japanese family name.
The Mazda brand does come from Matsuda but it also comes from a Zoroastran deity named Ahura Mazda, hence the spelling. Although in Japanese the brand is read Matsuda, is not written with kanji but kana, unlike other brands like Nissan or Nintendo. Toyota is similar, is a mispelling on purpose of the surname Toyoda; like Mazda, it is also spelled in kana.
@@OM19_MO79 Mazda was also used a well-respected brand for light bulbs in the early 20th century. I believe that was related to the Zoroastrian reference.
@@BixbyConsequence That “Mazda” which also made excellent quality vacuum tubes/valves was a British company that made products in the UK and France.
Mesh is a RF shield, from when they wanted this to work with an AM radio next to it in the office, along with an unshielded phone.
The keyboard also has mechanical 1 key rollover protection, you can only ever have a single numeric key pressed at one time.
Yes. I believe this as well. It's shielding.
Looks anti-glare to me
@@sparky6086 There is a ground connection to the PCB, via the one screw deliberately left without an insulator washer on it, and a PCB trace right around it.
@@SeanBZA why do you think this ground point between pcb's is connected to that wireless mesh?
@@Peter_A1466 The screw tab, face plate and mesh are all made of metal. Though it probably serves both purposes of shield and antiglare.
Marvellous content and thank you for having the courage to do a partial dismantle and reassemble of 50+ year old electronic artifact - the Japanese certainly show the world how to do it.
The red stamp is a hanko that reads “Matsuda” A hanko is a personal stamp that’s considered your personal signature in Japan & we’re only now, in 2021 debating fazing out the hanko. The main objection apparently is that signatures can be forged… even though you can pop down to your local Don Quijote & get a hanko with anyone’s name on it, no ID needed for ¥200 (aprox: $2).
Yes my father has one from when he visited Japan in the 1980's, a beautifully carved one.
these are ninin or mitomein. they are not consider as "signature". they are just name stamp.
jituin has similar meaning as personal signature in the west. but you have to register it.
@@fffwe3876 認印 (Mitomein) is a type of 判子 (Hanko), because 判子 is a general term that covers several types of identity stamp such as 銀行印 & 実印 (Jitsuin) & you can still get a 三文判 stamp for ¥200 at Don Quijote & use it for whatever you want, honestly or not & they’re all still a type of hanko.
@@nicholsliwilson there is a huge difference in the legal consequences. according to japanese Civil Code, only jituin has law binding effect. thats why people dont register a sanmon stamp from $shop. you can, but you dont want to do that for obvious reason. its like using "password1234" for login password.
@@fffwe3876 LOL! this is exactly what I mean. You seem to think people looking to commit fraud care about the civil code? Why on earth would anyone looking to commit fraud register any type of 判子 when they’re copying someone else’s? That’s not how the real world works.
This is the pitfall with having such a low crime rate across Japan, so many Japanese people just are not prepared to protect themselves when it does happen. It just doesn’t occur to people like @fffwe that criminals don’t care about the law because that’s so far removed from his own experience. It’s the exact same reason armed crime happens (everywhere, not just Japan) even though we have weapon bans, because only law abiding citizens give a damn about bans.
Wow, this takes me back! I used the little red indicators to mark thousands and thousandths when I was doing calculations, other times to mark thousands and millions, depending on the scale of the numbers I was working with. The decimal point itself was easy to see, but the markers acted like commas to break up long numbers.
20:37 Cute how you feel sorry for that lonely capacitor! 😄
Hi Fran, add-to-memory function is all right. You added 256 to memory at 1:58 and a second time at 2:16.
Very nice machine, thanks for showing
I caught that too, and the 100 was never added to memory either. Really cool device! Teachers in THAT day were justified saying, "You're not going to carry a calculator everywhere you go!!!"
Boy, the tank level of build brings a tear to one's eye! Interesting how nearly every component lead has the added black 'wrap' on the legs. Makes it appear quite odd when you look at it. Those display tubes are really stylish, dunno that I've seen such before.
This really is a spared no expense calculator and for what it cost back then, you could have brought a good car with that money.
The black stuff is hollow insulating material, sometimes called "spaghetti" , for the bare component leads, all hand placed. A lot of work to assemble esp. the leads of the display tubes.
Traces were likely hand drawn on transparency then a photographic process for mass production
Most of that is probably DTL instead of TTL so probably no need for decoupling
Yes DTL, with the diodes doing most of the work, and the IC cans likely containing only inverting transistor stages, for when you needed to buffer the output and regenerate the digital currents, or to act as drivers for the DTL stages.
Could be RTL too, or a mix. Why would TTL need more decoupling than DTL at the same frequency? (Are you thinking of totem pole outputs, drawing at switch over, like in CMOS?)
@@herrbonk3635 I’d think TTL would have sharper edges on transitions etc which would pull current spikes
Fun fact. You've probably seen Sharp ELSIMATE calculators but do you know where the name comes from. ELSI = Extra Large Scale Integration, back from when getting a calculator circuit onto one or two chips was a major achievement.
Due to the little dot for the 4 a 9-segment display for just the digit. That later 7-segment display was a real improvement.
You are correct but it is a thing of beauty that itron display. And these days with oled and LCD it wouldn't matter so much we could have a pretty display again .
The extra segment for the tail of the 4 is a really nice and subtle aesthetic touch, not to mention extravagant given the extra wire it requires.
Oh, I am _SO_ happy you've discovered these early Sharp calculators! Those early VFD displays are truly a beauty to behold!
I have a smaller unit, a QT-8D. Leading zero suppression killed the use of half height zeros, and VFD tubes like this fell out of favor. Many calculators of the era used half height zeroes, even on standard 7 segment displays, because it made viewing numbers easier when leading zeroes are not suppressed.
If you think, those hand drawn pcb traces make a perfect match with the display style. It's the inner beauty inside an obscure office machine!
Gorgeous!
It's a shame the zero had to be lower half.
I would pay money for an updated version with 'improved' zero. Fix it don't ditch it!
The 'F' position of the BCD display isn't normal (so it's not really a BCD display) , it's styled with a curve to make it look a little like the letter L. This means you can't use it make a normal looking zero.
It is just that you are used to a "full size" zero. I myself don't see a problem with it.
The half-heigt zero was probably done due to the fact that the leading zeros are not blanked, so that it is easier to see where your number starts.
Funny timing, I just donated the Facit-branded version of the same calculator to This Museum Is Not Obsolete / Look Mum, No Computer :-)
@@Ranger_Kevin Good on you sending it to that mad lad! He is my inner mad scientist's spirit animal. He is of equal awesome to have something like that.
Numbers look almost as handwritten and artistic, nice!
At first I thought it was a 6 segment display, but using extra segments to make the the numbers more readable is pretty awesome. I counted 9 segments though, there's an extra stroke on the 4.
The mesh is probably RF shielding, if it's connected to gnd somewhere. Back in the day they took avoiding interference a lot more seriously.
Mesh is an anti glare filter
@@rmora1 probably a bit of both, but most likely rf shielding as they would listen to the radio in offices.
@@hindsonracing numeric tubes don't give off rf and the mesh is coated with matte black for anti-glare
@@rmora1 Well spotted.
@@LarixusSnydes I use to build custom LED displays and we always had issues with glare on displays, this was a common fix.
Nice! This Museum is Not Obsolete just featured a Swedish calculator with the same display tubes last week. Never seen those before. Now there are two videos!
Was just thinking the same thing 👍
What a beautiful, artistic display! These are little poetic Japanese brushstrokes, not straight and stodgy western segments!
I have a Sharp Compet sold as a Facit 1131J. Same layout, but it appears to be from later as it has 3 or 4 LSI ICs in it, and it’s all Nixie tubes! I would have thought that the Nixie version would have predated the VFD one. Maybe Facit had to swap the artful display for a more traditional one for the Western market?
I still have part of the keyboard for one, with the mechanical rollover lock in it that prevents you pressing more than one numeric digit at a time.
Yes, I instantly recognized the brush strokes. That's absolutely wonderful to see.
Even the diodes are gorgeous.
@curiousmarc I don't think so. The Facit 1128 that I donated to lookmumnocomputer has the same tubes. So they definetely sold them in Sweden with these weird VFDs.
I wonder if any Kana display tubes have ever been attempted. :D
Hey friend, a place my dad were cleaned out the office probably in the mid 70s. He brought home a couple of calculators just like that, one was a sharp and the other one which looked just like it was a national semiconductor. And you’re right, the displays were awesome never seen anything like it since this video
The Iseden Itron script is my favorite digital display. The Burroughs (Sharp) C3260 I use at work has these tubes. The zeros are set up to show the way they do as many of these calculators replaced mechanical adding machines and they wanted to duplicate that look instead of blanking the zeros. The Friden 130 calculator and a few others were set up the same way.
A thing of beauty! This was a lovely, relaxing video too. I think the mesh layer may be to improve apparent contrast and reduce off-axis reflections.
Yes, exactly my thought: it's a diffuser mesh to help neutralize specular reflection from the tubes' glass surfaces by both breaking up the light that's striking the tubes themselves and also by imparting a sort of moire effect. Also, the silver mesh has a mid-range refractive index in the system being silvery grey, this would help with apparent contrast.
I've had it happen that placing my hand in front of VFDs made part of the display just go dark (happened on a VCR, was reproducible and took a couple of seconds until it even started to light back up), so maybe they had the same problem, maybe the mesh is to repel stray electrostatic...
I almost burst into tears when you opened the case it's so beautiful inside
Me too :')
Thanks Fran! You have the best videos!
One thing I am NOT sad about is not having to hand draw/tape traces any more! 😃
God those figures are gorgeous. How delightful. I'm very envious :)
9:52 I love the Led Zeppelin rift.
22:26 (pause here) It looks like the date code is printed on the label containing the letters FEC... just below that is 691107J, which may mean it was assembled November 7, 1969 (YYMMDD) or it could be July 11, 1969 (YYDDMM). I don't exactly know what the J means other than perhaps it was assembled in Japan.
The bulbs come forward out of the rubber leaving the wire lose through the grommet/shield. (try pushing it from behind with a little crab fork) Cut both off in the mid-length of its wire, measure the resistance of the working bulb, and the voltage the machine puts on the wires, then you'll have your bulb spec. Splice pigtails back together, add sockets and connectors if ya like. :) A gorgeous machine thank you for showing it off, and all the others too!
I counted 11 segments. The digit 4 adds a short bar. Add the dot and the apostrophe at the top end.
Yup. Re 13:57, I was going to say 9 in the core, plus 2 for dot and apostrophe… so yeah, 11 per tube, 9 per digit-per-se.
Which matches with the 11 transistors for multiplexing.
@@mjrippe indeed!
What's the purpose of the apostrophe?
@@sa3270 this snippet from Wikipedia should answer that (particularly the last bit):
For ease of reading, numbers with many digits may be divided into groups using a delimiter,[27] such as comma "," or dot ".", half-space " ", space " ", underbar "_" (as in maritime "21_450") or apostrophe «'».
the samp is probaly 松四, which is a family name, so its a inspector name
@14:29 I certainly see what you mean, Fran. They really are beautiful numerals. They have a truly unique 'thick-and-thin', calligraphic quality! (BTW: I love the positive and informative comments on this great channel)
This is very similar to the oddball soviet IV-2 (ИВ-2) tubes, except they don't have the tiny extra segment for 4.
I love those vintage 1960 - 70s Soviet vacuum tubes.
Even though I'm 14 yrs old :)
@@Purple431 art is art, and these things have something to appreciate for everyone
These remind me of nixie tubes because of their shape
If I'm not mistaken that was built on 12-2-1973. Older devices like that had the date code on the PCB.
This reminds me of a Scott FM stereo tuner once owned by a friend that used Nixie tubes for the display and punch cards to select the station frequency!
Way down inside 🎸🎶 (9:54) - "Whole Lotta Love" reference 🤣🤣🤣 Good one, Fran !! 👍😂
Finally! I’ve been looking for a video covering non-standard segmented display layouts for the better part of this year, I’m really happy you made this!
Wow, a tiny segment just for the "4" alone, just because it's more beautiful... I love it!
BigClive would have a field day with this.
Boy they did not want this machine shorting out
Back in the late 60s and early 70s I used to be a calculator repair guy. I used to repair calculators made by the Japanese company Buisicom. The main product was a basic 4 function unit with no memory. It had around 50+ plug-in PCBs and you got a hernia lugging around the repair kit. You would swap out the faulty card and at the end of the day repair the faulty ones back at base. Each card had a few logic gates built using standard discreet components. I remember the first hand held calculators that chewed through batteries and cost almost a year's wages (for me anyway). My first miniature calculator cost me over a month's wages and I still have it (somewhere).
I'm old enough to remember when they came out with adding machines with that type display (Nixie tubes?)
I thought it was amazing.
Ten years later they had pocket calculators with LED's and those were expensive paperweights.
In the 1980s there was an ANITA calculator sat on top of a cabinet at work. A shame that at the time I never realised its significance or even tried it. I left there in 1989 and the whole building is gone now so I have no idea what happened to that or the Racal Redac CAD systems I did regularly use there.
For the tabulation--it does make sense, because for whole numbers, for example $10.00, you can just type "10" and it will add the .00 for you. Easier for mostly whole numbers, you only have to manually add the cents for odd amounts. If it was the other way around, you would have to type 2 extra 0's for every single whole number.
The first electronic calculator I saw was a Texas Instrument one about the same size as that. This was in 1971 and it cost $4,000! It was purchased by the owner of a company that manufactured precision gears for Pratt & Whitney Aircraft. Adding machines had been around for a long time, but the advantage of the calculator was its ability to multiply and divide and it’s memory functions.
wow, what they called compact, or portable, sure has changed from then to now. I love looking at these older devices, so beautifully built. Thanks for sharing, Fran !
My dad had a handheld calculator that had floresent display tubes. It had 4 functions plus memory. It was battery powered. i think it was a Sharp also from the early 70s.
If that rubber boot is still flexible enough, you can replace those bulbs;
the round flange on the back side of the boot can be compressed with a diy 'split tube' tool and pushed out of the metal bracket toward the front,
then you can gently work diy split straws, "shims" between each side of the shrink-tubed wires and the boot gland to push the bulb and loom out of the front of the boot...
I wish I could mess with it with you, I've done similar extractions with very good results...
My best advice? tend toward compressing actions to complete the task and avoid stretching at all if possible.
Don't 'pull' rubber parts out of rigid supports, compress them and push them out.
Thin slivers of straw and scrap plastic packaging are your friends, you can release stuck rubber from mounting holes by gently shimming around the contact area after compressing the flange with a split tube...
Microscopically, new and old rubber are like an asphalt road and a cobblestone road respectively, The new rubber (asphalt road) can endure stretching, expansion and compression without much damage; the old rubber (cobblestone road) can endure compression, but expansion or stretching will cause 'stones' to shift out of place and "rip" gaps into the structural pattern...
bulb seems to be pushed forward i.e., towards front. once bulb is out, no need to take out rubber boot.
The red stamps says 松田, "Matsuda", which is a Japanese surname. Most likely an inspector's surname.
You had me at "SHARP". I owned many lovely SHARP devices back in the 80s.
I have a Toshiba desk calculator from the same era. It has about 250 transistors, no integrated circuits, and several thousand diodes. Its storage is dynamic RAM made out of a capacitor and two switching diodes per memory bit.
It uses Nixie tubes for display. It is assembled on six PCBs all using almost identical PCB technology - hand drawn tracks and sleeved component leads. The overflow and negative lamps are also neons rather than filament bulbs.
The metal mesh over the screen is most probably grounded and has to shield the unit from interfering with any other radios and or devices. “FCC Part 15”
Still have my Casio FX-10 calculator from about 1974, Nixie tube digit display very similar to what you're showing. Last time I checked it a few years ago, it still worked.
Digits in those fluorescent tubes look like they were drawn with kanji brush, nice ✨
Truly beautiful… a thing of beauty is a wonder to behold. Almost wish it could be in a pure transparent case so one could enjoy the sheer workmanship🎉
I love this type of show and tell of old technology. Thanks.
A beautiful piece of electronics. Thanks Fran!
The red stamp looks like a name stamp. Likely used as an approval seal for QI. In Japan they have stamps that are used for signature. The characters are in line with that, being both correct for a family name.
Whole Lotta Love to Fran for this great content.
The VFD's are actually 9-segment if you include the small horizontal tab for the number 4 on the right. :) All discrete transistor logic so this is vintage 1967-1971 time period. Integrated circuit manufacturers (Mostek, National Semiconductor, Toshiba, TI) started producing calculator processor integrated circuits in the early 70's which resulted in a significant reduction in volume, weight, and especially power consumption.
Fran, your assessment of the different subsystems is right on. The area were there are tons of diodes (especially near the banks of transistors) is likely the arithmetic logic section; every transistor-diode pair is likely an inverter OR a flop. A flip-flop will of course hold one binary digit of data.
As always, excellent video quality and brilliant work. Really appreciate have the camera held in fixed position (with presumably a good tripod). Great video!
Fran: The display of this Sharp is very similar to my father's old university calculator which he gave to me. It still works. It's a Commodore 64 scientific with 110 functions (considered a lot in the late 1970's) with glow red Light Emitting Diode display powered by a rechargeable nickel cadmium battery...and it's "Made in England." The original manual is still intact and it comes with a soft vinyl case. Love your program...watch every episode. ❤ Diane, Vancouver, Canada.
MnAU16/21 12:43 pm
Looks like the little tails on the 4s bring it up to a 9-segment, which seems extravagant.
A thing of beauty and joy for ever, lovey work Fran..
My dad had the same one growing up! Thx for the memory’s
what a treat to find this video!! thank you for this wonderful investigation on this lovely calculator!
The most beautiful display for shure! And a very well done machine. Wonderfull video, as always, Fran! Thank you very much.
I had a few of the tube display calculators with colorful keys, loved them.
I own the great-grandfather of this calculator; a 7 digit R.C. Allen mechanical calculator. Can add, subtract and multiply. Weighs a ton. Needs a new ink ribbon. It's interesting to see the incremental evolution of calculators, from the abacus to the mechanical adders (not forgetting slide rules), then more functions were added, then it went electronic as tubes (and filled the better part of a lab), then discrete solid state components, and now with vlsi/ulsi you can have an entire calculator running on a single chip. Guys on the Mannathan project would have died for a TI84+.
Whole Lotta Love, same era as the calculator. Thanks for the time machine Fran.
Those tubes are gorgeous!
that calculator is a throwback at a a documentary i re-watch from time to time, called "A video history of Japan's electronic industry", a 4-parter documentary you can find on youtube. It talks about the story from the beginning (just after WW2 with the birth of the transistor) to the time the documentary was probably shot (calculator wars, IC's, and technology surrounding VLSI's).
This a fantastic mini series! I've propably watched it for like 3 times :D
That was awesome Fran, I also thought to myself how well you control the camera. All the projects are very very interesting. Thank you Fran
Really enjoy the "handmade feel" of the tubes, each is its own length.
I have never seen that type of display and your right, it is so pleasing to the Eye. What is really cool, it makes the digits 1 - 9 appear as if they are standing up lol.
Interesting teardown, I worked on similar gear in the late 70's and the schematics were mind blowing! The keys look to be reed switches which unfortunately can fail, c.f. IBM token ring hubs, and often had a spring delay line for debounce which was often in a rectangular can under the main PCB.
Thank you Fran!
Fran, you are a great researcher, thank you for all your teaching. Steely Dan "Aja" T.V. Commercial (1978) Steve Gadd
Thanks for taking this beautiful calculator apart. Very brave. The mask in the display reminded me of my early 1970s Busicom that uses a mask around the very square segments of its gas discharge display to make them look a bit more conventional and to make the actually square decimal point look round. I collect calculators so always like it when you have them on. You still have the delights of the dynamic scattering mode LCD to explore, which, if you can find a working one, is intriguing enough even for somebody who isn't normally impressed by liquid crystal! I love mine but I'm told it will die in a few years because they all do in the end.
A true work of art there Fran!
The mesh shielding in front of the tubes are probably to protect the tubes from getting activated by the static charge that can build up on the front glass. Since there is no grid in the tubes the electrons can go in the wrong direction. I have some single tube VFD's and if you wave your hand in front of them they will flicker because of the static field.
Yes, cleaning the plastic window with a cloth would build up static charge, the mesh would be needed to shield the tubes from that.
The mesh is the grid of the tube. The cathode is the thin directly heated wire, then the grid and each segment is an anode/plate. Works exactly like a triode.
The clacking noise of the keyboard takes me back many many years to where I worked for a company and heard that noise. Strange and somewhat relaxing for some reason..
I love these old displays and display tubes!
9:52 Fran does her best Robert Plant impression ... lol.. .love it
I absolutely love your content!
Phenomenal display font. Really nice!
Those PCB traces look otherworldly. They almost remind me of Jomon pottery.
I also love the display... I've never seen a font on a segmented display like that.
This is a really cool device! It reminds me of the Toko Mini-8 calculator which had a single tube blue-green fluorescent display like this. When you switched it on and off, the display tube would make a noticeable _deenk-dink-dink_ noise as parts inside warmed and cooled.
Absolutely amazing!
beatiful indeed, i wish we still had that attention to detail nowedays!!
You are so right, I have never seen such a beautiful cursive-style display, so much nicer than traditional.
That is a very well made calculator with an unusual display. Amazing circuitboard with a lot of quality components as well as Germanium cat whisker diodes. Thanks for sharing.
That is gorgeous!
I find early electronic displays fascinating. A huge amount of ingenuity and elegance of design appeared in a few years in the late 60's and early 70's. COS LCDs are another beautiful but largely forgotten technology...
What an interesting package for an IC.
Amazing! I'd assume the mesh was to cast a slight shadow inside the display so that the meager wattage of the tubes would't be overwhelmed by the ambient light, like when you're outdoors and the sun is too bright to see your phone so you put your hand over it to shade it. Its also possible that LimaVictor down there is correct, that it's for RF shielding, or maybe its both.
First time a circuit board reveal has ever made me swear out loud. 😄 Holy cow, that thing is packed! Who'da thunk the unique "Japanese brushstroke segment" tubes wouldn't've been the most fascinating thing to see here. Wild to see the ton of splayed legs on those alien-looking multi-flipflops (?), too. Interesting that the Iseden display tubes supported floating commas in addition to the periods, but Sharp didn't use 'em. Guess they plum ran out of space for driver circuitry!
A side-benefit of leaving comma display to those sliding red plastic tabs is that the calculator would be able to display digit grouping both in Western 1,000-based grouping or East Asian 10,000-based grouping.
Built with pride. Love the old glass diodes. NEC made some of the best TV transmitter equipment. At 17:14 looks like a repair to circuit.
I remember that early calculators used RPN (Reverse Polish Notation). One advantage was the reduced number of key operations.
I still use one at work for badness, nobody ever takes my calculator...
Is that maybe what the little switch with the "X, N, -" might be for?
So they're actually 11 segment 'tubes, (and there's 12 digits..!) What a beast. Fault finding would be tricky if it ever decided to misbehave..
The little ceros are bizarre at cute at the same time. NICE DISPLAY
Wow!! those are really unusual tubes! I have an old Bell and Howell desktop multimeter that uses nixie tubes, which is pretty cool, but the font on these VFD tubes is just fantastic