this is a
computer or at least back in the 1930s
40s and 50s the person operating it was a computer you see back then a fully
automatic calculator like this one was
mindblowing allowing people to add subtract multiply and divide large
numbers without the use of pen and paper these days that's all done
electronically but when Richard a local fan reached out and said hey I've got
one of these we jumped at the chance to become the very thing we love the most
computers thanks to Signal RGB for sponsoring this video signal RGB is a
free application that syncs RGB lighting across your entire setup and works for
Brands like Corsair Razer Logitech and more check it out at the link down below
when I was in school teachers would insist we learned to do long division by
hand because you're not going to be going around carrying a calculator
everywhere you go well jok's on you miss
Parsons cuz now everyone is doing exactly that and trust me this baby does
long division but back in the '90s Miss Parsons could be forgiven for thinking
that pocket calculators wouldn't be as ubiquitous today seeing as many older
folks back then may have grown up with something a lot more like this the
freeden stw10 if we were to go back another 30 years there's a good chance
we'd find one of these chunky Boys on an accountant's desk in fact you may have
already seen something like this either online or in a stirring historical drama
like hidden figures no it's not a typewriter although it does sort of
share some similarities there's a sliding Carriage on top and a large set
of keys on the body but these are all numbers and there's no ink or paper
needed at least not any that you insert into the machine itself the first set of
mechanical number displays on the carriage is the accumulator row which
can display results up to 20 digits long for reference most pocket calculators
today only display around 8 or 10 and my phone can enter up to 15 digits before
it starts using exponents the role below that is the counter register it serves a
couple of different functions just like how our new indoor sweater from LTT
store.com keeps you warm and boosts your confidence don't quote me on that the
first function is how it acts as an item counter when adding or subtracting and
the second is operations counting when multiplying or dividing you can lock
these rows or clear them with some button
presses or you can use one of these guys down here to set where the decimal
starts for division I want to start it
there now down here one numpad would be
Bush leag so we got two uh this little
one over here is used only for entering multiple cans more on that later and the
big one is used for everything else each
digit has its own column and you enter your total value by pushing down Keys as
they would appear on paper so for example for 1337 we push them in order
like this 1 337 if any column has nothing pressed
that counts as zero it's a little confusing at first but you get used to
it pretty quickly everything is housed in a shell made of what we think is
aluminum covered in plastic that's pretty easy to take off and there's a
giant pad of foam underneath to keep this mechanical beast from shaking your
table to death I mean this thing is
heavy oh I'm doing math I feel smarter
you can see on the inside it's basically a giant mish mash of Gears levers
Springs and arms it it's like mechanic
spaghetti in there it is incredibly complex and the amount of engineering
that went into something like this is absolutely insane there were earlier
models like the 1941 freed and h8 but these were often limited to addition and
subtraction and weren't driven electronically the stw10 came out a few
years later and gave simple computers like us the ability to multiply and
divide big numbers easily hey what do
you say we crunch some numbers so to add you enter a value on the main main pad
and add it to the top row like this bam now we enter whatever number we
want to add to that number by entering new values and pressing the add button
again so what it's actually doing is setting a value on a number of dials and
then ticking everything up by the new value in sequence it's a lot like how
you would do paper math adding each digit until there's an overflow then
adding the Overflow to the end if we want to subtract it's basically doing
the exact opposite by starting with a value and then decreasing it in
sequential order by the new value multiplication Works in a similar way
it's basically just addition in groups
except this time we get to use the cool multiplicand numpad I've been waiting so
long this one actually works like what you'd see in a modern calculator where
you enter each digit serially from left to right and it brings up your value on
this little display here next we enter our multiplier on the big numpad
press The Malt key and look at it
go that is so cool we'll get some slow-mo footage but as it's going you
can basically watch it in real time working through the numbers brute
forcing addition of our multiple cand as many times as I've told it to because
again I am the computer division is
basically the same thing but backwards like subtraction enter your first number
on the big keypad set your decimal place and hit
enter dived this puts the carriage to where it
needs to go according to our decimal point clear the keyboard if it didn't
automatically and enter your divisor on the same
keypad now we're going to have to hit both of these divide Keys we'll get to
why there are two in a moment but for now look at it go
man that never gets old just like hitting that subscribe button never gets
old we've got our eyes on an anti- kther a mechanism video in the future that you
don't want to miss now for the most part this should just work it crunches
through the numbers to the nearest decimal point and gives us our result
which is uh uh give me a
sec 33.3 repeating of course but if you were to
accidentally divide a number by zero the machine can get stuck in an infinite
Loop what back in the 40s and 50s if a
room of accountants or something was using automatic calculators without this
handy div stop function we have right here there'd actually be a guy in the
room whose job it was to basically just listen for this infinite Loop and walk
around resetting machines
now this bad boy is pretty well lubed thanks to Richard did you lube it up oh
yeah oh yeah but rapidly moving metal moving for a long time gets really hot
so if there was no button or no Button Man you'd find out what was at the end
of that infinite Loop molten
destruction at this moment you're probably screaming at me at the top of
your lungs Riley why does this have two division buttons why I'm going to need
you to calm down by the time Division and multiplication were added someone
else had already beaten freden to the punch and patented a single button
division system preventing freden from including it in this model if you press
only the left division button the division will take place but you'll get
only the 10 complement of the expected result now the stw10 was only designed
to do addition subtraction multiplication and division but some
Masters of the Universe actually figured out how to get square roots on this
thing how you ask
Wizardry uh tin in so in order to
actually do a square root on a calculator like this you have to follow
a number of different types of algorithms to actually do it these
machines don't have a push square root button but math has developed algorithms
that you can use to quickly calculate a square root on a machine like this or on
paper or anywhere else for this machine the algorithm that we we're looking at
using is the sum of odd squares for our sake it works and I'll take you through
the steps of how it works for this 69420
first up you move your Carriage all the way over and make sure that it's aligned
with the 10 digit of your number then you enter plus five
times now clear off and move the
carriage all the way over now we'll go through and actually get into the weeds
of calculating this number out you put a five in the next column over this is the
column we're actually calculating on and you start subtracting away as we're
going through each increment we're essentially adding another one of the
odd numbers through some math magic but as we're subtracting away subtract one
subtract two that's when you know that's the number you're looking for you add it
back shift The Carriage over one shift
the five over one and start again and this is where it starts getting a little
bit repetitive but it
works there's another underflow add it
back clear the five move it over shift
the carriage and
again underflow add it back clear the
five move it over ship the carriage and
subtract
they underflow it back and repeat in
this particular algorithm we're breaking it up by individual digit similar to
like what you do on paper so we're starting with the biggest number and
slowly shifting our way down as we move on and that's an easier way to try to
handle numbers that are five plus digits long especially for a square root carage
and now that we're on this last line we can't move the five over anymore but we
just clear off shift over the carriage and do the same step again just without
the extra five and now we've done the square root
but where's the answer we have a whole bunch of different numbers on the board
for this it's actually the board itself we have two 6
3 47 6 7 5 4 one so this kind of shows the
power of you know interesting approaches to try to solve calculations that used
to take minutes hours days in an order of magnitude less time how long would
that take you to do on paper I'd have to learn how to do it on pen and paper
first so what happened to calculators like this well freden sold thousands of
these things primarily to accounting and insurance companies and then ended
production of the stw10 in 1966 as the
ec130 a transistor calculator with a 13-digit capacity started taking over
freden was bought out by by singer known primarily for their sewing machines at
the time and eventually died off in the 70s as pocket calculators like this one
hit the market I mean as awesome as this
absolute unit is it's pretty obvious why
these started winning out 12872
multiplied by 437 and
go yeah uh sorry freen uh still love you
if you want to try and buy one of these and try and restore it yourself they
seem to go from anywhere between $2 and $500 if you can find one you'll also be
lucky if yours arrives in perfectly working condition if you want any tips
on restoring or using them make sure to check out Richard on Twitch twitch.tv/
scobot asaurus we'll have that as well as any affiliate links down below thanks
to Bessie Footwear for sponsoring today's video Bessie Footwear is known
for being lightweight easy to pack comfortable and most importantly water
resistant designed to keep you moving Bessie releas their new everyday move
shoes they've got enhanced breathability and added support making the style
perfect for The Adventurous or those looking for something sportier they've
got a pull tab to make taking them off and putting them on super easy vegan
suede lace cages extra midsole cushioning and the same water resistant
diex technology that you would find in other vessie shoes you're going to want
to wear them everywhere the Dual climate knit material keeps your feet warm
during the winter and cool during the summer so why wait stay dry and get your
vessie shoes today at v.com Linus techtips you leave even get $25 off
using Code Linus Tech tips at the checkout thanks for watching everyone if
you enjoyed this video make sure to check out our model M video the greatest
keyboard of all time reborn in which lonus stole my jacket and now I have it
back screw you man