The first calculation result was correct, you pressed the M+ twice

@SuperVstech

2 жыл бұрын

Yeah, I noticed she must have forgotten when she pointed out the place holder pointers. And pressed it again.

@randombloke82

2 жыл бұрын

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”

@SuperVstech

2 жыл бұрын

@@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.

@beavonator

2 жыл бұрын

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.

@AmstradExin

2 жыл бұрын

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.

@josha254

Жыл бұрын

​@@AmstradExin noooo

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.

@CharlesPruden

2 жыл бұрын

Yes. I believe this as well. It's shielding.

@Peter_A1466

2 жыл бұрын

Looks anti-glare to me

@SeanBZA

2 жыл бұрын

@@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.

@Peter_A1466

2 жыл бұрын

@@SeanBZA why do you think this ground point between pcb's is connected to that wireless mesh?

@CharlesPruden

2 жыл бұрын

@@Peter_A1466 The screw tab, face plate and mesh are all made of metal. Though it probably serves both purposes of shield and antiglare.

The red stamp reads 松田 Matsuda (as in Mazda the car maker who used another spelling); it's a common Japanese family name.

@OM19_MO79

2 жыл бұрын

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.

@BixbyConsequence

2 жыл бұрын

@@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.

@ebkesq72

2 жыл бұрын

@@BixbyConsequence That “Mazda” which also made excellent quality vacuum tubes/valves was a British company that made products in the UK and France.

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).

@SeanBZA

2 жыл бұрын

Yes my father has one from when he visited Japan in the 1980's, a beautifully carved one.

@fffwe3876

2 жыл бұрын

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.

@nicholsliwilson

2 жыл бұрын

@@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.

@fffwe3876

2 жыл бұрын

@@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.

@nicholsliwilson

2 жыл бұрын

@@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.

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.

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

@lironmtnranch4765

2 жыл бұрын

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!!!"

God those figures are gorgeous. How delightful. I'm very envious :)

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

@SeanBZA

2 жыл бұрын

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.

@herrbonk3635

2 жыл бұрын

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?)

@williefleete

2 жыл бұрын

@@herrbonk3635 I’d think TTL would have sharper edges on transitions etc which would pull current spikes

@MrDuncl

2 жыл бұрын

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.

Gorgeous! It's a shame the zero had to be lower half.

@FranLab

2 жыл бұрын

I would pay money for an updated version with 'improved' zero. Fix it don't ditch it!

@heedmywarning2792

2 жыл бұрын

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.

@martindejong3974

2 жыл бұрын

It is just that you are used to a "full size" zero. I myself don't see a problem with it.

@Ranger_Kevin

2 жыл бұрын

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 :-)

@rallyfeind

2 жыл бұрын

@@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.

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.

@MikeSmith-sh3ko

2 жыл бұрын

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.

@haweater1555

2 жыл бұрын

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.

Numbers look almost as handwritten and artistic, nice!

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! 😄

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.

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!

@Skraboing649

2 жыл бұрын

Was just thinking the same thing 👍

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.

@MikeSmith-sh3ko

2 жыл бұрын

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 .

@glarynth

2 жыл бұрын

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.

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?

@SeanBZA

2 жыл бұрын

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.

@Bobbias

2 жыл бұрын

Yes, I instantly recognized the brush strokes. That's absolutely wonderful to see.

@SixOThree

2 жыл бұрын

Even the diodes are gorgeous.

@Ranger_Kevin

2 жыл бұрын

@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.

@AmstradExin

2 жыл бұрын

I wonder if any Kana display tubes have ever been attempted. :D

Wow, a tiny segment just for the "4" alone, just because it's more beautiful... I love it!

I almost burst into tears when you opened the case it's so beautiful inside

@MLX1401

2 жыл бұрын

Me too :')

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.

@freddyburger5574

2 жыл бұрын

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.

@senilyDeluxe

2 жыл бұрын

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...

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!

You had me at "SHARP". I owned many lovely SHARP devices back in the 80s.

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!

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.

@rmora1

2 жыл бұрын

Mesh is an anti glare filter

@hindsonracing

2 жыл бұрын

@@rmora1 probably a bit of both, but most likely rf shielding as they would listen to the radio in offices.

@rmora1

2 жыл бұрын

@@hindsonracing numeric tubes don't give off rf and the mesh is coated with matte black for anti-glare

@LarixusSnydes

2 жыл бұрын

@@rmora1 Well spotted.

@rmora1

2 жыл бұрын

@@LarixusSnydes I use to build custom LED displays and we always had issues with glare on displays, this was a common fix.

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.

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).

This is very similar to the oddball soviet IV-2 (ИВ-2) tubes, except they don't have the tiny extra segment for 4.

@Purple431

2 жыл бұрын

I love those vintage 1960 - 70s Soviet vacuum tubes. Even though I'm 14 yrs old :)

@BartJBols

2 жыл бұрын

@@Purple431 art is art, and these things have something to appreciate for everyone

@Purple431

2 жыл бұрын

These remind me of nixie tubes because of their shape

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!

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.

Thanks Fran! You have the best videos! One thing I am NOT sad about is not having to hand draw/tape traces any more! 😃

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.

@MrDuncl

2 жыл бұрын

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.

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.

I counted 11 segments. The digit 4 adds a short bar. Add the dot and the apostrophe at the top end.

@DavidLindes

2 жыл бұрын

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.

@mjrippe

2 жыл бұрын

Which matches with the 11 transistors for multiplexing.

@DavidLindes

2 жыл бұрын

@@mjrippe indeed!

@sa3270

2 жыл бұрын

What's the purpose of the apostrophe?

@DavidLindes

2 жыл бұрын

@@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 «'».

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.

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

9:52 I love the Led Zeppelin rift.

@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)

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 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+.

BigClive would have a field day with this. Boy they did not want this machine shorting out

Way down inside 🎸🎶 (9:54) - "Whole Lotta Love" reference 🤣🤣🤣 Good one, Fran !! 👍😂

Looks like the little tails on the 4s bring it up to a 9-segment, which seems extravagant.

The red stamps says 松田, "Matsuda", which is a Japanese surname. Most likely an inspector's surname.

the samp is probaly 松四, which is a family name, so its a inspector name

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.

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...

@ahsanyunas

Жыл бұрын

bulb seems to be pushed forward i.e., towards front. once bulb is out, no need to take out rubber boot.

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..

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 !

The little ceros are bizarre at cute at the same time. NICE DISPLAY

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...

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..

The main circuit board is pure art, and what beautiful art it would make. It's all about software and programming now, discreet component design is all but gone, even microprocessors are taken for granted. We have come so far, so fast. Yet we had to wait quite some time to start the ball rolling, even though the concept of automation, programming, and computing, and their potential applications were understood, at a time when we didn't even have toilet paper.

FranLab: Getting Surgical. Love it.

Those circuit board are a thing of art.

Digits in those fluorescent tubes look like they were drawn with kanji brush, nice ✨

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”

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.

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.

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.

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!

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.

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!

If I'm not mistaken that was built on 12-2-1973. Older devices like that had the date code on the PCB.

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

I hope I don't come across as self promoting but seeing that font suddenly brought back a flood of memories because it's almost identical to the font I built from zero for a paper ticket printer in the early 80s. I remember I was sick of seeing square 7 segment style characters

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.

You are so right, I have never seen such a beautiful cursive-style display, so much nicer than traditional.

GORGEOUS!! I once had a Friden calculator - yes, THAT one, all rock logic, not an IC in sight, LCD display - and while the LCD could have had any arbitrary characters they wanted (vector) they made it the most boring 7-segment emulation you might imagine. Actually, I expect you've seen it. This is muuuuuch nicer. :) AND it has memory! ;D

9:52 Fran does her best Robert Plant impression ... lol.. .love it

The glare of the globe Fran. Man those are some tight numbers! Mucho germanium diodes.

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).

@MLX1401

2 жыл бұрын

This a fantastic mini series! I've propably watched it for like 3 times :D

I had a few of the tube display calculators with colorful keys, loved them.

That mesh is most likely an RF shield. Pretty sure those Nixies radiated some trash.. Imagine a 1970s dispatcher office with a phone PBX, a PA system or even a two way radio for the delivery trucks. I repaired old model video terminals that would wipe radios and TVs for 20 yards. Probably single-handedly created FCC part 15 class B regulations.. I love the sleeves on each of the vertical components. Thanks Fran.

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.

What an interesting package for an IC.

Incredibly beautiful.

Hey Fran, did you notice that the key switches use perminant magnets and reed switches?

@brianclark1223

2 жыл бұрын

I wondered that with magnets glued on lol

@freddyburger5574

2 жыл бұрын

Yes! My Brother Pro-Cal 408 uses a similar system. Provides great feeling, responsive keypresses and virtually zero chance of contacts oxidizing!

neon blues...pleasing to the eyes

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.

Whole Lotta Love to Fran for this great content.

I was in suspense over the reassembly.

A *NINE* segment display! (Don't forget the tallywacker sticking out of the 4.)

The electronics are stunning, all hand made and beautiful l layout

VFDs really are beautiful, and those calligraphy-ish digits, wow! (Posy also did a video about VFDs, you should really check it out.) The whole machine is a masterpiece of Japanese craftsmanship. When you showed the keys from below I wondered for a second if they are hall effect switches, but I guess not.

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.

H.E.C. sounds like Hayakawa Electric Corporation a.k.a. Sharp. 011EPA kind of resembles their later much longer part numbers though it might be something else since there are other parts numbers on the board. The NEC IC's clearly carry date codes, but I'm not sure how to decode them. The 9 at the beginning could mean 1969. The 9K on the Hitachi 2SC641 transistor would mean November 1969. I haven't watched the full video yet, but if there's a manufacturing date stamp somewhere (In vintage Japanese equipment in general) you might not recognise it as a date, since they often used era encoding. For example, August 20 1969 would be written as 44.8.20 since 1969 is Showa 44 (the 44th year of emperor Hiro Hito).

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.

I love this type of show and tell of old technology. Thanks.

A thing of beauty and joy for ever, lovey work Fran..

The numeric font is really an art! Much much better than the conventional 7-segment LED! Like comparing the work of an artist with a kindergarten kid!

The banks of metal can logic gates and the big glass diodes are absolutely marvelous to look at. They dont design stuff like that anymore.

what a treat to find this video!! thank you for this wonderful investigation on this lovely calculator!

The next calculator generation from Sharp (also sold under Burroughs name) got even more interesting inside, using first generation MOS chipsets. There were no facilities in Japan capable of mass producing the chips in the quantities needed at the time, so Sharp sourced QIP packaged chips from Rockwell in the USA.

A beautiful piece of electronics. Thanks Fran!

Past 3 AM, logging and labeling up to my 57th battery set of Eneloop cells. Thanks for the Friday night entertainment. :D

The precursor of TTL was DTL, meaning Diode-Transistor-Logic, after all with the help of resistors you can have NAND or OR logic and combine that with transistors to invert or amplify/decouple it to get all kinds of logic circuits. Really interesting to see this.

The most beautiful display for shure! And a very well done machine. Wonderfull video, as always, Fran! Thank you very much.