1971's Smallest Battery-Powered Calculator: Dictaphone 1680 

Update! Check this out: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-C-o6aznNuGo.html With the generous help of Curious Marc and crew this lovely calculator now lives again. They also dove into how the General Instrument chipset works!Delightful!

In the 70s my mom did accounting with a big noisy heavy mechanical adding machine. She didn't trust electronic calculators because they were "too small".

The guts of this calculator look like the inspiration for every TV show bomb from 1970-1990.

11:59 Those "burn marks" I expect are actually from the casing of the wires reacting with the plastic over time. They do look like burn marks but you can see that the wires have been in close contact with the plastic and so I think they're the result of a chemical reaction between the two. Great video as always!

The 'burn' marks on the battery by the wires are the elastomer used in the wires leaching into the plastic. You see this on vintage computers that people have wrapped the power cords around.

The display tubes are panaplex, work exactly like nixies but instead of digit shaped cathodes they are in a 7 segment arrangement. Pretty much that's their only similarity to VFDs as they do have a gas fill (I believe neon and maybe argon) to facilitate plasmic discharge unlike VFDs which operate under a vacuum and light up due to thermionic emission striking phosphors. As for the missing F and G segments on the tubes, since they are all out this suggests the tubes are driven multiplexed. I'd start by looking for cold solder joints leading up to the tubes but it's most likely the open collector cathode drive high voltage transistors for those segments have died and need to be replaced.

I’ve seen problems on early segment displays like this before, and it’s quite easy to fix! Each segment is usually driven by a general purpose transistor, which can occasionally fail and take out the same segment in every digit. (I glimpsed a couple of the transistors in the video, they look like Mitsubishi ones) If you can probe around and find which transistor drives those particular segments, fixing the display should be as simple as replacing it.

How about Ron at Joe's Classic Videogames? He's always fixing 7 segment displays on vintage pinball machines from a similar era. He might be able to give you some clues as to what the problem is.

Maybe this is an excellent excuse to do a collab with the master restorer on vintage computers, CuriousMarc.I'm sure his electronics group can fix the Calculator, but also it would be great to see you two chat about his collection and general computer stuff.

The "Oooh, arts and crafts" line caught me offguard. LOL Love seeing the insides of these older machines, even if it's just a calculator.

I have a weird memory of the late 80's when companies were attaching "free" unrelated stuff to their products. My parents brought home a box of laundry detergent with a solar-powered calculator glued to the lid. 10-year-old me thought it was so cool. My dad just sighed and told me about the first time he was able to replace his slide-rule with a four-function calculator that he paid over $100 for. Edit: He went to engineering school in the early-mid 60's, but not sure when that purchase was, exactly.

If you asked me, I'd say I'm not particularly interested in old tech from back in the day. However, LGR's obvious passion and enthusiasm for his hobby has kept me watching his content for years. Doesn't hurt that he's got a super soothing voice that's perfect for just throwing on a playlist and going to bed with. I may not know a lot about this stuff, but I could hear LGR talk about it for hours easy. I don't even remember exactly how I stumbled onto the channel years ago, but I've been a fan ever since. There's just something about listening to a person genuinely excited about their hobby and sharing it with you that's quite appealing to me.

I remember seeing this cutie in a vintage market awhile ago, it’s so dopey I love it

6:41 I agree, and I'd recommend people take a look inside old electric organs. Many of their chips can look similar and you could very easily throw together a prop from those parts without having to destroy a calculator. it's a shame, but electric organs are just too big to keep most times. I've had to destroy about 10 of them in my life, but the parts are so good. It really wouldn't be hard to make a fake replica from old electronics instead of destroying a complete calculator.

You could ask CuriousMarc if he can help you, he's an incredibly good electronics technician

I like how you can even see that the traces were laid by hand. Such wow.

The amount of love this guy has for old technology is so heartwarming. If anyone should have this kinda stuff in their hands, there is no one better than the LGR

Thanks for making another calculator video! It's been too long since your last one. Lots of us use calculators every day at work (accounts, here), so the more retro attention they receive, the better IMO

I would say you need a schematic. It's probably something in that line of capacitors or transistors under the battery. If you had the schematic, you could check voltage points to trace the issue.

I am not going to lie that calculator is very stylish. I would totally use that today.

The marks on the battery are from a chemical reaction between the plastic and the rubber of the wires. This happens a lot with old microcomputers that were stored with their cables wrapped around.

Curious Marc might have an idea. Him and his restoration guys are damn near gods of old electronics

A really fascinating video! Nice vintage calculator and great view of the internals. I enjoyed watching this vintage tech!

[Smooth jazz fades out smoothly] I do enjoy your subtitles

8:24 Love those gold legged chips. When I took my Yamaha DX7 apart to fit an expansion board I saw it used chips a bit like that. No expense spared.

I love these kind of videos. Keep it up lgr !!!!!!!

Very cool to see what's inside in old calculator like this, never seen this stuff before :)

Really cool. Thanks for showing the insides of it. Hopefully you can get it going better so you can do your retro calculations more completely 😁

Nice,it all adds up to LGR ,great channel

I'm sure Adrian (Adrian's Digital Basement) would have an oscilloscope to check out what the chips etc are doing and see if it can be fixed :D. Collab? :P.

The videos are always good whether the equipment works or not. Keep up the great work!!!

ah, great video, it reminded me i bought a similar calculator (sanyo ICC-0081) way back in the 90's at a thrift shop. Luckily the battery hadn't exploded (yet). Had a bit of fun playing around with it today, thanks!

I would certainly like to see a follow up on calculators of the era. I've be curious to see if one I grew up with (and have no real memory of that would help me describe it currently) might just show up. I played with it in the 80's, but I suspect it went back to the 70's.

As a calculator person, this one is delightful. I have recently been using a Casio fx-83WA from 1996ish. It's pretty fun.

This is Curiousmarc and his friends electronics territory. Those guys are AWESOME fixing really old and complex systems.

The lid coming loose while talking about how it's not that intigrated is some great unintentional comedy. Great stuff.

My suggestion would be to reach out to either CuriousMarc or Mr. Carlson's Lab. Both do a ton of vintage electronic repairs, and i guess it would be a great opportunity to do a colab?

My father worked for Bowmar who made some early calculators. I still have several prototypes he brought home. Because of a TI lawsuit they decided to exit that market and concentrate on government contracts though.

Hi Clint...what a lovely piece of history you got. I can only recommend another youtuber that I watch a lot messing around with old computers from the 60s and 70s. Try to contact Curious Marc from the computer museum in California. His whole team play around with old technology a lot. They even resuscitate one of the original Apollo 11 (Moon Landing) computers from the 60s. Thanks for keeping posting good content. Greetings Criss

I rebuilt mine two years ago and it still rocks! New batt pack (NiMH upgrade from NiCD), new charger/power supply and general clean up. Beautiful device, in terms of design and functionality! I was lucky to find one in almost mint condition.

Calculators are so fascinating, i dont know why,but its so cool.The VFD displays ? This Sanyo is dope !!!

Looks like a tricorder from Star Trek TOS!

So cool. I still have my father's Hitachi KK 181B, circa 1973. So similar to this one: rechargeable battery, charge meter, VFD display, reed switches, even the visor. The battery and meter are long gone, but the rest still worked last time I plugged it in.

I remember love how you really seamlessly your videos..... The music, the intro..... I.... Whoops. There goes that. 😊

This PCB and ICs... 💖💖💖 No wonder it cost that much back in the day!

I suspect the missing segments in the display is duff driver transistors. Those TO106 round transistors can often be problematic in old radios etc,. Apparently they haven't aged very well. A suitable replacement would be something like MPSA42 or MPSA92 high voltage switching transistors, depending if they're NPN or PNP.

Reminds me of my Dads calculator from that time period. He loves that thing and keeps it in perfect condition

Those are 7 segment Nixie tubes like Panaplex (even more rare than regular nixie tubes). It looks like you're missing "F" segment to all digits, so either a contact to F's is broken or the BCD to 7 segment decoder is broken or has bad joint. Those tubes are all in parallel, the grids are separate, the control is dynamic multiplex. Search the problem in "F" connection or see if some of the tubes is shorted on F segment to grid, in some cases, each segment can receive its supply trough a resistor (check it) so 8 of them needed for each row of the 7 segments and dots, there also could be a transistor driver switching them, check all those points and elements on the "F" segments path up to the IC (integrated circuit). On the backside of each tube you can see how the connections are made and trace where they are going out of the tube. The problem should be easy to troubleshoot.

I think Ben Heck did a repair video on something that had a similar problem with the display, but he basically said that it was just because it was an old part. I don't think he tried to fix the display itself cuz he didn't have the tools

I love it! That one hit a chord in me - as a kid I used to buy all sorts of calculators on flea markets, always having my pearents worrying that I get an electric shock at some point when powering on one of them xD

Read in the Sanyo ICC-82D manual that the "E" is "Error (over flow lamp)". If I'm not mistaken, those are filament bulbs. The gas inside may have leaked causing them to no longer function.

Nice old beast, those displays are a lot closer to Nixie tubes than a VFD. VFD's have a heater filament, where these don't, they are (as are nixie's) kind of a glorified neon bulb. If you are lucky the lost segment could be one of those transistors & associated caps etc, you'll probably need a scope to see the multiplex in action. Looking back at it, the row of 'resistors' under the lower bank of transistors, the one too the left is off at an odd angle - have a look, has it pulled free?

The start Price for the version with Nixie Display Starts at 290€ fully working and with charger. Thank you for that video. ☺🍀

Put this in perspective, this calculator was made two years after the first moon landing

Between this channel, Matt’s tech moan and 8 bit guy.. I’ve been watching for years.. many years. However each night for the last month before bed I’ve been binge watching all 3. lol.

I'm a calculator colector TI fan boy what you have here even in its current functional status is an amazing piece of history the chips look amazing and the tubes too, yes nixie calculators are the joy of every collector but I also enjoy my panaplex display, vfd and led too, nice find !

Kind of like when everyone destroyed the graflex camera parts for lightsabers

Awesome! Will dovetail nicely with the upcoming VisiCalc tech tale! Can't wait!

LGR is the kind of dude to upload a 6 hour long video about an ultra rare electric toothbrush and TV remote combo from 1968 and still make it interesting.

Try Mr. Carlson's Lab, He mostly does old radios and stuff... He is less destructive and he has above all the touch and respect for old electronics... Try him and see I'm not sure about calculators but he is very good choice.. (in my opinion)… I was also looking for a green display calculator which I used when I was much younger but I cannot seem to find them … they continue to evade me... Hope you fix the calculator.. it's not very often you find tech that is old and 100%... Cheers! remember Mr. Carlson's Lab...

That calculator is in such good cosmetic shape. Too bad it isn't a nixie tube display though.

I love the red display in these old calculators. So much better and easier to see than the ones that came after and are still used today.

Super cool, i also just love this kind of stuff! Had an early 70's mains powered Citizen (can't recall the model name) desk calculator which looked pretty much the same inside with these four chipsets but those were made by Sharp. Or at least they said so. Slightly different looking "VFD-tubes" with that lovely light green glow as you normally see on later 70's pocket calculators. I found it at a second hand store for roughly 10 euros. Today i only have left my Canon Palmtronic LD-81 from my birthyear 1975, which i bring out to use occasionally. It works a treat and i love the clicky metal membrane keys on it 😀.

This looks like a job for Adrian's Digital Basement.

$495! To put this into context, by late 70s I heard my parents say, "Who can afford a $300 per month mortgage?"

I'm lucky to have a mint condition device, albeit with renewed NiMH batt pack. Minimal contact cleaning got all digits (panaplex type) working again. Even got the instructions and original cleaning cloth. Lovely device! Great video!

I know that the last iBook G4 uses one of those glass switches to tell the circuitry if the lid is open or closed! Insane to see that it is such old but beautiful crafted technology! And how beautiful are those chips inside of there! Gold and white! What a nice device man really!

Old calculators are fascinating. Some, pretty stylish too, and this one, I'd use in a cinch.

Could the three non-functional tubes be creating an open circuit and cause the functioning tubes to have incomplete displays? (Forgive me if this is a stupid theory!)

Those key switches blew my mind! So simple, durable and reliable. Just brilliant!

When I was a kid, my dad cleaned out an office and brought me home a sharp calculator from about that same time and it had that theme display in it

Man, I hate when people destroy stuff like this to make props. The same thing happened with the C96 Mauser after Star Wars came out with people destroying them to make blasters.

Those old 1970s calculators are like early microcomputers back then, even though now they’re so redundant when you can have a very sleek and tiny device that can do calculations nowadays!

I had 80's polish Elwro calculator with similar VFD tube display but light green. And it was powered from the wall socket. Even in the 80's these calculators were outdated, but they were pretty reliable and the display had that pleasant glow. When thin Citizen calculators appeared Elwros became obsolete.

Great video love and collect early calculators but you beat me by 3 years my oldest is 1974. Great video more calculator videos please.

6:30 If you think that's bad, take a look at Texas Instruments Exactras. Considering they were super cheap and mass produced to hell and back, they're nearly impossible to find nowadays and go for bonkers money because the bubble strip that goes over the LED displays was used on Luke Skywalker's lightsaber in Episode 4. Balls.

This kinda reminds me of the Star Trek TOS tricorder.

Curious Marc sent me. Glad it's working.

50 years... Very pretty. Looking at that sponge disintegrating made me think that in a few hundred thousand years future explorers and historians won't even know they should be looking for transistors within a piece of shiny silicon they would have found in a pile of golden little pins.

Good news, Clint; there _are_ a couple of prop companies that have started making reproduction boards for the belt gizmo props. So, hopefully, the poaching of these mathematical marvels will taper off.

The Ghostbusters belt gizmo can be mostly 3D printed now, that's the way to go instead of destroying vintage calculators.

So cool! I hope you get it working

That would make an absolutely fantastic collaboration project between you & Louis Rossman. The lad knows his **** when we are talking about electronic circuit board repairs. Give the guy a call. I would love to see this happen, Clint.

My guess. The capacitor turned into a resistor for that one element in the nixie tube. It would have been handy if something popped with magic smoke so it could be identified. Ten years after approximately, I got a credit card size calculator with a solar panel for power. I like the miniaturization. The calculating machine plans in the clockwork age were apparently the size of a cathedral. Just for collating projectile targeting. Didn't get built.

The screen angrily alternates between C and J. Apparently, it expects you to follow the train. 😅

LGR, you have the coolest voice, sense of humor, and if I may say so, a handsome fella

I know a certain man who loves fixing vintage electronics and those beautiful gold ceramic early IC packaging. CuriousMarc, one of his biggest projects was being on a team that restored an AGC for the 50th anniversary of Apollo 11, also restored a xerox alto.

I hope you find a working one sometime soon. Those early calculators are the fossils of modern technology.

TIP: There's only one person i would send my stuff to, and that's the Apollo hardware repairman himself. The one, the only ... curiousmarc. He'd fix this in his sleep. :)

Being able to see inside was super cool.

Great video, and I hope you can get this fixed. Technically, the Royal Digital III was a smaller (single chip!) calculator that came out in '71 - but it only had a four digit display(!!) - hence the advert for the Sanyo being specific about it being the smallest *16 digit* calculator. At the time, the number of digits a calculator had was a big deal, and most calculators had a button to switch between 'high' and 'low' digits to make the most of their limited displays.

I found a calculator with a very similar design language (as would be expected) in a thrift(?) store, a Sanyo ICC-1123 (it looks quite similar to the ICC-0161 shown in the ad at 2:00)

At first I thought the incomplete zero symbol was intentional, because I know some old calculators display a "lowercase" zero so you won't confuse it with an 8.

I think the gas discharge tubes are more like Nixie tubes, basically each segment is a tiny neon indicator. There's no vacuum in them, just a low-pressure gas. Once the striking voltage is reached between the electrodes, current will flow through the gas, creating a plasma which excites the gas to glow the distinctive orange colour (although different gas mixtures can be used to create different coloured gas discharge glows). Nixies are a specialised kind of GDT, where there's a cathode grid across the front of the tube and multiple anodes stacked on top of each other, one for each number (or character) in the tube. That's very different from a VFD, which work more like vacuum tubes. They use a hot cathode which boils off electrons that fly through the vacuum tube to hit the anode. The anode is coated with a phosphor, which glows when struck by the electrons. The cathode is negatively charged, and there's a control grid between the cathode and the anode that's positively charged. Electrons are accelerated from the cathode, through the control grid to the positively charged anode, which glows. If the anode is negatively charged, it doesn't glow. Because GDTs need to strike across an inert gas, their working voltages are much higher than VFDs, typically 160-320V (depending on segment size). That means this kind of low-voltage device requires a circuit to generate the high voltage required to run the tubes, and high voltage transistors to switch on the segments. VFDs operate at much lower voltages, typically up to 24V at the high end, which is one reason they quickly overtook GDTs as the preferred display technology from the late 70s all the way through to the 90s when LCDs started to take over. Fran Blanche has a good video explaining the difference, "Know Your Displays - Nixie vs. VFD Tubes".

normally don't get excited about calculators, but love those old white ceramic and gold ICs, and the way this thing is built in general. There's just something incredibly impressive about electronics right at the start of the transistor and IC era. Fun thing about the battery meter: on the portable compact cassette recorders from the same period that component also serves as VU meter for the recording level, just with slightly different colouring

here so fast 🥰

The sheer build quality of this... this... artefact. This is a statement, an extension of life. People bought this to enhance their lives. Not to run away from it. Not just a today's consumer good.

looks like we found the inspiration for the the Original Star Trek series's tricorder. =D Awesome!

Sounds like a good collaboration opportunity with Adrian's Digital Basement.

Yay new LGR!!!!