Pocket Mechanical Calculator - Addiator/Addifix

this is a neckerman attifix 9 a pocket calculator and i believe this one is from the 1960s though this design is significantly older than that now there are a number of things that make this thing truly fascinating it's super thin for one not much bigger than a modern smartphone it uses a stylus and it can be used to do the four basic math operations of addition subtraction multiplication and division but all it uses are simple pieces of sliding metal now the attifix isn't all that remarkable because it's about 80 years late to the party this calculator is a clone of the adiator which was designed by lewis tranche in the 1880s i've mentioned multiple times now the manufacturing revolution that allowed the miniaturization of parts like this the design really didn't change all that much and you can see in the original patents to the toothed sliding metal design though the attifix is able to do subtraction by simply flipping it over a feature added fairly quickly after the original introduction now using an adiator clone such as the attifix is very simple and done with the stylus now this isn't the first usage of a stylus which actually dates all the way back to stone carvings but it is one of the first usages for it in a computational device many people like to credit things like pdas as being the first things to use a stylus but really this is a much older type of device than that now the stylus on the attifix or adiator is used to hook into the little holes next to the digits and move the sliders using this you can pull down and set a digit resetting is done with a handle on the top so if i wanted to input 5 i would put the stylus into the hole next to the 5 and pull all the way down then a 5 is displayed in the register now the outer fix here is using the convention of the time of denoting decimals hundredths and thousandths with different colors and this would be helpful for currency operations mostly so something to keep in mind is that if you want to enter in say 23 you would actually do it over here now addition on this is incredibly simple if we wanted to add 2 to our 23 to make it 25 we would just pull down again next to the digits near the holes and now we have our answer 25 where this really gets clever is when you carry a digit if we want to add 7 to this to make it 32 we go up to the 7 but we can see that the stylus is now in this red area well that's because when we pull down it's going to lock and show us an indicator with an arrow pointing up this means we have to pull the counter all the way up move over into the next slot and push the next digit of the register down and we now have our answer of 32 this operation is not too dissimilar to pinwheel calculators of the time that would automatically rotate the next digit over when you overflow a register's counter however you do have to manually do it on the attifix and that's just a side effect of it being totally flat you can't do a whole lot of rotating when you don't have 360 degrees of movement so addition is very simple on the adiator and just for example again let's do 73 plus 54 and there's our answer 127 but what if we want to do subtractions well the adiator would originally shipped with the ability to rotate it upside down in an additional set of registers on the bottom this would allow you to pull the same numbers away to be able to change the digits however this out of fix has the subtraction counter on the bottom of the calculator instead and then they are able to print the numbers upside down you'll notice that these would be in the same position as it would on the others but this makes it a little bit easier to mentally understand you'll also notice when reset the digits on the subtraction side are all red this means that you're going to have to overflow all of them if you want to do a subtraction from zero and these calculators really aren't designed to operate in negative values so you're not going to want to do that you would want to start out with a value on this side first actually we're running into a slight issue here you can under flow the digits on here and the reset mechanism cannot reset or clear those so you'll actually have to pull these down manually and then reset there anyway let's do 100 minus 25 so we're going to pull 100 down here and flip it over for subtraction so to subtract 25 we'll first pull five from the first column and we're told to carry then we need to come over here and we're immediately given a carry but we're going to go ahead and go down to the 2 and do that and now we see 75 very very simple you just have to remember you input the first digit on the addition side and then the actual subtraction on the subtraction side all right now let's step it up a notch and do some multiplication now multiplication on here is really not all that much more difficult than addition you just need to keep in mind that you need to actually do a little bit of thinking for the multiplication and multiply by digits moving over rather than just hammering away entering in the numbers so if we want to do 12 times 12 we're going to break it down by digits we'll multiply the first digit twice entering in 12 in the first column twice and then the next digit will be entering in 12 once and now we have our answer 144. now of course if you want to do something that will be single digit and have higher values it's going to take a while so if we want to do five times seven it's going to take a little bit of time here yeah not the most practical thing but it is usable now we've covered addition subtraction multiplication and that's it and those are usually the only features that these types of calculators are advertised with however you can actually do division on these but you really do have to know what you're doing and the only reason i know what i'm doing is because i own a comptometer and have studied it quite deeply so i'm going to do a comptometer style division on this and i'm not going to explain it first just because i want you to see what it takes but know that it is actually possible now i'm not even going to use the subtraction side for this because it's not necessary thanks to nine's complement this is one of my favorite division problems 365 days divided by seven days which tells us the total number of weeks in a year approximately and that if you punch it into a digital calculator is the correct answer offset by one digit all right now that was a pretty big complicated example and i just wanted to kind of show you how crazy you can get with division on here but let's break it down with a more simple example of 24 divided by 6 which actually covers a lot of bases that we need to do now if you want to know more about how this exactly works i highly recommend you check out my comptometer video because i'm not going to go over everything here and i did in that video but let's just go ahead and start out so this division is done with nine's complement which means that we're going to be adding numbers that are the 9's complement to the number that we want to subtract so since we're doing division here we're going to be subtracting 6 and that means we're going to be working with 3 except for the division we'd need to add 1 for reasons that i explained in the comptometer video so check that out but let's go ahead and start here and we're going to be adding 4 to subtract 6. now we can't subtract 6 from 2 without underflowing so we move on to the next digit now because we have this two here we actually need to add this digit the number of times it's visible in the next one so let's go ahead and add four twice and we've run into a little bit of an issue and we had to carry which means that this is now three which means we need to go one more time and now we're done we've caught this digit up to this digit however we still have a value in this digits register now because this value is greater than or equal to the number that we're actually trying to do the division with we need to continue one more time and after we do this carry we see a four appear here and we're zero here so we're all clear and because this is zero and it's zeros all the way across we're now done now the answer for 24 divided by six is actually four and we printed the answer one digit over this is just a quirk of how this division style works it offsets the answer by a few decimal places depending on how big your problems are but that is actually the correct answer you just need to do magnitude approximation now that was pretty quick and easy wasn't it you would expect something like this to have to flip back and forth between subtraction and addition multiple times to do a division operation but no that's pretty easy and there we go we have all four major mathematic operations done on a calculator that fits in a pocket that's pretty cool isn't it now you might wonder well can you do square roots or you know other complicated mathematic operations and while technically yes you never would have on that because slide rules exist and slide rules existed before this did so really if you wanted to continue on and do more complex mathematic operations you would have used one of these and while this video is definitely not going to go into the operation of a slide rule i bet that this is a combination that would have been used for quite some time and i just find that somewhat amusing well i hope you enjoyed this quick video taking a look at the adiator clone adifix here that i have thank you to tomato licious for sending this i've been meaning to get one of these for quite some time and it is every bit as interesting as i had hoped it would be um these are frequently called arrhythmometers and while the original patent for tranche's version was called an erythmograph i believe at no point should these have ever been called erythmometers because that's something completely different so call it an adiator that's really what it is anyway hope you enjoyed this look and if you want to see more calculator stuff i recommend you subscribe because i'm fascinated by these things if you want to support the channel i am on patreon but for now that's it and i'll see you next time you

Channel: Tech Tangents

Views: 456,074

Keywords: Tech Tangents, AkBKukU, main, Calculator, 1960s, addifix, addiator, slide, mechanical, pocket, portable

Id: cT8fSGHHiAs

Length: 12min 2sec (722 seconds)

Published: Mon Aug 17 2020