Yes - RPN is solid gold. I used "regular" calculators in high school, but freshman year in college I bought an HP-41CV RPN calculator. And never looked back. It was the first device I ever programmed - it's what I LEARNED to program on. So my mind is "stack oriented" right from the start. Then I discovered Forth, and once again there was no looking back. I've written Forth systems numerous times over the years - it's a system one person can write, and it can be extended to do ANYTHING. It's BETTER.
4:45 "where's a calculator" For a moment there, I thought he was going to adjust for inflation on his modern calculator and I'd have been so pissed that he didn't do it on the old one.
I remember being taught Reverse Polish Notation in my cs class and being amazed just by that. I can't even imagine how much time went into getting a machine like this to work and basically being the first piece of technology to effectively implement Reverse Polish Notation. This is probably one of my favourite numberphile vids
Does he have his own show ? He should have his own show, this man is everything i need when i feel like the world is letting me down and can't enjoy anything.
For those wondering, the barred-L of Jan Łukasiewicz is in Polish pronounced like an English W. His name would be pronounced "Yahn Woo-kah-SHYEV-eech" (Oh--and the Polish letter J is pronounced like the English Y, hence "Jan" is indeed pronounced "Yahn")
As an Air Force Electronic Computer Systems Repairman in the late 70's, one of my correspondence courses included a section on that wire delay line memory. My source described the wire as being a special magneto-strictive nickel alloy which would deform when subjected to a magnetic field. Same basic idea and I'm sure that there were different variations on this design. For fun, read the first page of Asimov's first robot novel, "Caves of Steel", where he describes bits of data rippling through pools of mercury (mercury delay line memory was used in some early computers) and that the data readout was recorded onto a piece of wire (we had wire audio recorders long before the Germans came up with tape recording -- Bing Crosby liberated some of that German equipment towards the end of the war and then pioneered recording his radio programs). It's always fascinating to see how they used to do things.
I would love to work for Cliff. I would just be a lackey in his garage/laboratory, tinkering with stuff and handing him tools. All he'd have to do is buy me pizza and teach me about stuff. 😄
The "piano wire" delay/memory is very much like the slightly older Hammond Reverb, audio enhancement system. Even the delay time: "Dozens of mS" in the Friden, 35mS in a Hammond. Same torsional waves. Difference is the Hammond is driven "linear" and the Friden slams big bit-bangs onto the line. And Hammond encouraged end-reflection for multiple bounces, Friden must damp those somehow. And they are coiled differently-- Hammond like over-size pen springs to fit in a slim tank, Friden hose-coiled because they knew they had the room, and maybe their fatter wire didn't coil-up small. Be glad it was not the Mercury-tank delay/storage used in one of the early UK mainframes. More toxic Mercury than most people ever see.
RPN is just how people calculate on paper: To add two numbers on paper you write them down and then add. You don't add and write them down, thats the polish notation, nor do you write one number down add and then write the second number down, which is infix. So I find it very peculiar that people say that RPN is hard and counter intuitive. If you want RPN calculator check what HP offers. They don't cost a dime but neither are the low end ones too expensive.
My first calculator (at work) was an HP-97, with a magnetic strip reader/writer - and, of course, RPN! I also remember working on an RCA transistor radio, where the (germanium) transistors were discrete sockets.
So in order for the memory to be continuous, it has to cycle, right? Like when the "on" torsion wave gets to the end, it's recycled to the beginning and transmits again? Is that the way this thing worked? If so, the length of the wire determined how many bits you could store, right? Just trying to wrap my head around this--what a cool storage system!
John Gibbs Computerphile did a video about it in the context of building a reproduction of one of Harvard's early computers, those used five foot pipes full of mercury.
Some nerds insist that RPN mode is superior. They are correct. I put my HP Prime in RPN mode and it's hard to go back to other calculators. Problem is, it does screw up certain apps and make some of the more complicated functions difficult or impossible.
I love reverse polish notation because it makes everything easier. I wrote a Java library that parses postfix expressions and can symbolically differentiate them; and I was able to do it because I didn't have to worry about writing a parser that knows order of operations thanks to the nature of postfix notation
Few things to think about: - a torsion wave in the string has some finite velocity of propagation down the string, v - if you "pluck" the string every t seconds, you can say that bits are separated by v*t -- that's a bit length - capacity of string is its length divided by the bit length, c - for each bit read at the end of string, write it again at the beginning of the string
I wondered this, too! Wikipedia has a great article on it, search for "delay line memory". The type used in the Friden calculators was "magnetostrictive", seems like a relative of the piezoelectric effect, but results in a twist. Super cool!
ogardZ, so it functions as a loop, where the computer itself only needs to repeat what it's just 'heard,' and the delay provides enough space to put in a lot of bits before the computer 'hears' the same bit again?
jadegecko I think so. That's why they were called also sequential access memory. You have to wait for every loop to go through to retrieve a specific bit. Random Access Memory, instead, let's you access information at any direction of the memory at any time.
Greetings from Poland ;) BTW. if you want to speak his name more correctly "cz" at the end of Łukasiewicz's name, you should say like "ch" like in chicken ;)
One nice thing about RPN also is, you can stay with the order of operands, eg (3+4)x5 = 3,4,+,5,x The operators will simply take the first two values from the stack as operands and operate on them.
+Olaf Doschke "you can stay with the order of operands" - not necessarily: 3 + 4 * 5 requires you to re-sort (as 5,4,*,3,+ for example), as does 5 * (3 + 4)
@@freshrockpapa-e7799 Fair enough, but both your examples involve resorting the operators... which admittedly are not operands. However, resorting it is.
I would love to record this guys voice to a record then use his voice to scratch in samples into music on my turn tables. "Plink! plank.There goes the bit"
Did you ever get a microphone too close to a speaker and hear the howl? That was an acoustic memory of the sound. The Friden cleaned up the pulses (1's and 0's) and amplified them before sending them back around the wire several times second, over and over. The longer the wire the more bits you could put in the memory loop.
I still use RPN on an HP-41c calculator simulator running on my iPhone... Not sure if that's meta or just bizarre, but I LOVE RPN. It's so much faster and sweeter than the standard way calculators work today.
I use Realcalc on Android for the same reason. It shows multiple registers at a time, and you can swap registers around. Far superior to the single register displays on most calculators. My desk calculator is a 23 year old Casio that's still running the battery it shipped with. I've been using it so long I even found a (Very minor) bug in its code.
So how many bits of data can be travelling along that delay line at any one time? In other words, what is its capacity, please? I see about 16 turns on the wire, top and bottom, but don't know the average diameter or data propagation speed along it. Cliff does mention one or two figures for propagation delay, but not the clock speed, which might be another way of determining the capacity, assuming that more than one piece of data is on the wire at any time. Thanks.
I have 2 Monroe mechanical calculators, the logic is similar to RPN. Type in number, crank to add to register, type in number, crank forward to add or backward to subtract. Keep cranking forward to multiply. The older bigger one works. The little one I hope to get it working.
I use Hewlett Packard Reverse Polish Notation calculators in preference to any other type. As far as I understand it HP had a patent on the use of RPN in calculators which prevented others from making RPN calculators (or at least would have required them to have paid royalties to HP) so RPN never really took off except for engineers and financial types using HP RPN Scientific or Financial calculators. Shame I think in terms of RPN, its always seemed to me the natural way to work. Perhaps I'm just weird, I use an RPN calculator on my LInux running desktop computer also.
When I started learning Japanese I was the only one in the class not to be baffled by their grammar. I put this down to having learnt RPN in the 70s. Japanese is a sort of RPN language!
About last part: those are acoustic waves - there is no need for another term. Rayleigh waves (seismic) are acoustic too-based on mechanical movement of environment they propagate in.
The difference between a calculator and a car is that miniaturization can happen in calculators with the limit of a visible display and usable keyboard. We have had calculator watches back in the 80's. The size of the car, on the other hand, is constrained by the size of the payload, the size and weight of the payload constrains the size and weight of the structure, which in turn constrains the required power of the engine. There are remote-controlled planes of the size of a pocket calculator. But while the pocket calculator is still useful to calculate, the pocket airplane is just a toy that can't take you, your family and 3 luggage pieces 400 miles out.
This is a great question. Today, there are built-in rules to detect division by zero: not allowed. But what if those safeguards didn't exist? What would happen? It's a fascinating question, and it would depend on the architecture of each calculator. I believe I saw Matt Parker talking about it on one of these videos at some point ... might be time for a little research.
I was wondering how transverse waves would not get stuck where the wire is supported. Torsional or longitudinal waves would not but I only thought of longitudinal not torsional. Brilliant!
Well logic is amazing but how those engineers come up with such ideas, and how the manage to implement them, there are truly talented people in this world.
Jan Łukasiewicz is pronounced more like "yan wukashevich" (this is still a tiny bit off because polish consonant sounds aren't exactly the same as in english, but close enough)
What’s the purpose of sending the information down the piano wire? I get that it delays the information by a few milliseconds... but why? What does the delay accomplish?
so that memory line is basically an audio feedback loop, right? and the one thing i completely don't get is how the machine recognized the beginning of the stored data when reading from that memory
When I bought my first PC in early 80's I was working in express mail service in central Helsinki. When in a coffee room I told what I'd done everybody asked how could I aford it. I looked around perplexed and asked: "You always brag about buying new cars and no-one asks how you can afford them. When I, who don't even own a driver's license, buy a computer instead of a car you wonder how can I afford it." They went silent. On same side I was in a public sauna when I heard people talking about maintenance cost of their cars and I told them that my car costs me exactly 7000 FIM (this was before euros). They said that one cannot even get car insurace on that sum so I must be lying. I told them that the year pass for Helsinki public transportation cost 1800 FIM and that leaves 5200 FIM unaccounted for and that is 100 FIM per week for taxi. Then they asked do I spend 100 FIM every week on taxi and I said of course not, but in some week I might use 200 FIM on taxi. So the next question was that if I bought something big and needed to bring home how can I do it in public transportation and I answered that that what the taxi was for. They had no more questions.
You buried the good part about reverse polish notation (RPN) in an extra video !?? RPN has been used in computers from the 60's (maybe earlier) until today, It is how the calculations like (2 + 3) * 5 are done. Computers solve this like the following: 2, 3, plus, 5, times --- push 2, push 3, add (pop 2 and 3 add them, push the sum(5)), push 5, multiply (pop 5 and another 5, multiply and push the product on the stack) 25 the answer is left on the top of the stack. It is beautiful. Jan Łukasiewicz was born Dec 21, 1878 and invented a similar notation in 1924 (from Wikipedia). Hey Google, Dr. Lukasiewicz deserves a doodle!!
I don't quite understand how that's considered "memory", it sounds more like it's just sending data via vibrations over the wire... But how is that holding onto the data as "memory".
You have to loop it. After the vibration gets to the end of the wire, it is amplified and fed back into the beginning. So the bits are kind of circling through the wire for so long as you need them. The longer the wire, the more bits "fit" onto it.
![เปิดบ้าน นาราเครปกระเทย 1 ไร่ ขายขาดทุนหลัก10ล้าน เอามาใช้หนี้!!! l [Nickynachat]](http://i.ytimg.com/vi/0jz84VFWVP4/mqdefault.jpg)
Cliff is always a joy to watch his energy and enthusiasm makes everything enjoyable
Yes - RPN is solid gold. I used "regular" calculators in high school, but freshman year in college I bought an HP-41CV RPN calculator. And never looked back. It was the first device I ever programmed - it's what I LEARNED to program on. So my mind is "stack oriented" right from the start. Then I discovered Forth, and once again there was no looking back. I've written Forth systems numerous times over the years - it's a system one person can write, and it can be extended to do ANYTHING. It's BETTER.
What an contagious enthusiasm. He is the Dr. Emmet Brown of TH-cam...
Doc Brown's got nothing on Cliff!
Great scott!
4:45 "where's a calculator"
For a moment there, I thought he was going to adjust for inflation on his modern calculator and I'd have been so pissed that he didn't do it on the old one.
Cliff wouldnt let us down like that :P
I remember being taught Reverse Polish Notation in my cs class and being amazed just by that. I can't even imagine how much time went into getting a machine like this to work and basically being the first piece of technology to effectively implement Reverse Polish Notation. This is probably one of my favourite numberphile vids
Does he have his own show ? He should have his own show, this man is everything i need when i feel like the world is letting me down and can't enjoy anything.
$255 extra if you wanted automatic square root. That's quite the upgrade price! Could this calculator handle negative numbers?
For those wondering, the barred-L of Jan Łukasiewicz is in Polish pronounced like an English W. His name would be pronounced "Yahn Woo-kah-SHYEV-eech"
(Oh--and the Polish letter J is pronounced like the English Y, hence "Jan" is indeed pronounced "Yahn")
Cliff truly makes me happy - I rewatch the cliff playlist when I'm feeling down. Adding more videos to that playlist is great :)
Is Cliff using a USB-MicroUSB cable in his demonstration instead of a piece of string? That's hilarious.
Godminnette2 - I saw a little irony in that. What a difference 55 years makes.
Pic of Ramanujan right there. This guy is a legend.
As an Air Force Electronic Computer Systems Repairman in the late 70's, one of my correspondence courses included a section on that wire delay line memory. My source described the wire as being a special magneto-strictive nickel alloy which would deform when subjected to a magnetic field. Same basic idea and I'm sure that there were different variations on this design.
For fun, read the first page of Asimov's first robot novel, "Caves of Steel", where he describes bits of data rippling through pools of mercury (mercury delay line memory was used in some early computers) and that the data readout was recorded onto a piece of wire (we had wire audio recorders long before the Germans came up with tape recording -- Bing Crosby liberated some of that German equipment towards the end of the war and then pioneered recording his radio programs). It's always fascinating to see how they used to do things.
I really want to see how big the smile on Brady's face at 4:29.
I always use RPN calculators. Have them on the phone and on the PC.
I really think that RPN deserves the whole separate video.
I would love to work for Cliff. I would just be a lackey in his garage/laboratory, tinkering with stuff and handing him tools. All he'd have to do is buy me pizza and teach me about stuff. 😄
The "piano wire" delay/memory is very much like the slightly older Hammond Reverb, audio enhancement system. Even the delay time: "Dozens of mS" in the Friden, 35mS in a Hammond. Same torsional waves. Difference is the Hammond is driven "linear" and the Friden slams big bit-bangs onto the line. And Hammond encouraged end-reflection for multiple bounces, Friden must damp those somehow. And they are coiled differently-- Hammond like over-size pen springs to fit in a slim tank, Friden hose-coiled because they knew they had the room, and maybe their fatter wire didn't coil-up small.
Be glad it was not the Mercury-tank delay/storage used in one of the early UK mainframes. More toxic Mercury than most people ever see.
i love this man i wish there was just a boat load more content with him in it
RPN is just how people calculate on paper: To add two numbers on paper you write them down and then add. You don't add and write them down, thats the polish notation, nor do you write one number down add and then write the second number down, which is infix. So I find it very peculiar that people say that RPN is hard and counter intuitive.
If you want RPN calculator check what HP offers. They don't cost a dime but neither are the low end ones too expensive.
I really liked the part about torsional waves.Torsion is an under-appreciated aspect of physics...
My first calculator (at work) was an HP-97, with a magnetic strip reader/writer - and, of course, RPN!
I also remember working on an RCA transistor radio, where the (germanium) transistors were discrete sockets.
1:47 He litterally jumps from excitement.
I love this man
So in order for the memory to be continuous, it has to cycle, right? Like when the "on" torsion wave gets to the end, it's recycled to the beginning and transmits again? Is that the way this thing worked? If so, the length of the wire determined how many bits you could store, right? Just trying to wrap my head around this--what a cool storage system!
John Gibbs Computerphile did a video about it in the context of building a reproduction of one of Harvard's early computers, those used five foot pipes full of mercury.
I cannot get enough of Clifford.
Some nerds insist that RPN mode is superior. They are correct. I put my HP Prime in RPN mode and it's hard to go back to other calculators. Problem is, it does screw up certain apps and make some of the more complicated functions difficult or impossible.
Was the Cliff the inspiration for the doc in back to the future? He is just like him.
I so wish I was taught by someone as eccentric as this. He's amazing
Such enthusiasm is absolutely joyful to watch
I’ve never seen someone who looks as happy as this guy!
Who doesn't love watching his videos?
dead people
I don't not love watching them. ;-p
I love reverse polish notation because it makes everything easier. I wrote a Java library that parses postfix expressions and can symbolically differentiate them; and I was able to do it because I didn't have to worry about writing a parser that knows order of operations thanks to the nature of postfix notation
Would have liked to have seen a photo of Carl Friden (my grandfather) in the background.
I have ADHD and yet I've never had as much energy as this man.
I love RPN so much.
still don't know how sending things through a long wire works as a memory. it just seems to delay the output but doesn't really store anything?
Few things to think about:
- a torsion wave in the string has some finite velocity of propagation down the string, v
- if you "pluck" the string every t seconds, you can say that bits are separated by v*t -- that's a bit length
- capacity of string is its length divided by the bit length, c
- for each bit read at the end of string, write it again at the beginning of the string
I wondered this, too! Wikipedia has a great article on it, search for "delay line memory". The type used in the Friden calculators was "magnetostrictive", seems like a relative of the piezoelectric effect, but results in a twist. Super cool!
ogardZ, so it functions as a loop, where the computer itself only needs to repeat what it's just 'heard,' and the delay provides enough space to put in a lot of bits before the computer 'hears' the same bit again?
jadegecko I think so. That's why they were called also sequential access memory. You have to wait for every loop to go through to retrieve a specific bit. Random Access Memory, instead, let's you access information at any direction of the memory at any time.
jadegecko, pitthepig
Yes, exactly.
Acoustic memory is something I never heard of...but wouldn’t that have applications for today’s technology? That acoustic memory sounds incredible
The name “Jan Łukasiewicz” is pronounced as /jän wu.kä.'ɕɛ.vit͡ʂ/, so roughly as “yahn wooh-kah-shyeh-veech”.
Greetings from Poland ;)
BTW. if you want to speak his name more correctly "cz" at the end of Łukasiewicz's name, you should say like "ch" like in chicken ;)
kukilet //Dawid B. how is the first letter pronounced?
similar to english w
@Antonio Barba: The name “Jan Łukasiewicz” is pronounced as /jän wu.kä.'ɕɛ.vit͡ʂ/, so roughly as “yahn wooh-kah-shyeh-veech”.
4:52 "Where's the calculator?" what? Are we playing Dora now? Isn't it right there? a big ass calculator :D
If immortality would be in a pill, this guy should get it. :D
Friden: *makes billions of pounds selling calculators*
SHARP and Casio: I'm about to end this man's whole career...
One nice thing about RPN also is, you can stay with the order of operands, eg (3+4)x5 = 3,4,+,5,x
The operators will simply take the first two values from the stack as operands and operate on them.
+Olaf Doschke "you can stay with the order of operands" - not necessarily: 3 + 4 * 5 requires you to re-sort (as 5,4,*,3,+ for example), as does 5 * (3 + 4)
@@dlevi67just do 3 4 5 * +, and for the second one 5 3 4 + *, no sorting required
@@freshrockpapa-e7799 Fair enough, but both your examples involve resorting the operators... which admittedly are not operands. However, resorting it is.
i love this guy already
I would love to record this guys voice to a record then use his voice to scratch in samples into music on my turn tables. "Plink! plank.There goes the bit"
I love his enthusiasm- he's also like a real life Doctor Emmet Brown!
RPN, Jan Łukasiewicz :) Pozdrowienia od polskiego widza Numberphile :)
Did you ever get a microphone too close to a speaker and hear the howl? That was an acoustic memory of the sound. The Friden cleaned up the pulses (1's and 0's) and amplified them before sending them back around the wire several times second, over and over. The longer the wire the more bits you could put in the memory loop.
I guess you could say this was a calculator UNBOXING
RPN FTW❤
It's cool to see Cliff on TH-cam. That reminds me, I haven't read The Cuckoo's Egg in a long time :)
I still use RPN on an HP-41c calculator simulator running on my iPhone... Not sure if that's meta or just bizarre, but I LOVE RPN. It's so much faster and sweeter than the standard way calculators work today.
I use Realcalc on Android for the same reason. It shows multiple registers at a time, and you can swap registers around. Far superior to the single register displays on most calculators. My desk calculator is a 23 year old Casio that's still running the battery it shipped with. I've been using it so long I even found a (Very minor) bug in its code.
FWIW my desk calculator is an HP28C - real, not simulated.
@@peglor Which particular Casio calculator, and what is the bug?
I think that in 4:00 he meant to say 2 enter, 3 enter, 5 times, plus. Instead, he omitted the plus at the end. Or did a misunderstood?
this guy makes me so happy :)
So how many bits of data can be travelling along that delay line at any one time? In other words, what is its capacity, please? I see about 16 turns on the wire, top and bottom, but don't know the average diameter or data propagation speed along it. Cliff does mention one or two figures for propagation delay, but not the clock speed, which might be another way of determining the capacity, assuming that more than one piece of data is on the wire at any time. Thanks.
seeing the amount of digits on the screen, with a max of 9 in each of them, I'd guess that's a realistic approximation of the maximum
I have 2 Monroe mechanical calculators, the logic is similar to RPN. Type in number, crank to add to register, type in number, crank forward to add or backward to subtract. Keep cranking forward to multiply. The older bigger one works. The little one I hope to get it working.
This guy is a treasure
I remember my HP35 and HP45, both of which used RPN
I found it so easy to use once I understood it
I use Hewlett Packard Reverse Polish Notation calculators in preference to any other type. As far as I understand it HP had a patent on the use of RPN in calculators which prevented others from making RPN calculators (or at least would have required them to have paid royalties to HP) so RPN never really took off except for engineers and financial types using HP RPN Scientific or Financial calculators. Shame I think in terms of RPN, its always seemed to me the natural way to work. Perhaps I'm just weird, I use an RPN calculator on my LInux running desktop computer also.
When I started learning Japanese I was the only one in the class not to be baffled by their grammar. I put this down to having learnt RPN in the 70s. Japanese is a sort of RPN language!
That's exactly what I though too. I was like "oh, Japanese has a really easy grammar" and everyone else was just looking at me like "wtf dude?" :-D
About last part: those are acoustic waves - there is no need for another term. Rayleigh waves (seismic) are acoustic too-based on mechanical movement of environment they propagate in.
Electroacoustic memory!😮
Cars should also cost $1 today!
Go ahead and make one :D
The difference between a calculator and a car is that miniaturization can happen in calculators with the limit of a visible display and usable keyboard. We have had calculator watches back in the 80's. The size of the car, on the other hand, is constrained by the size of the payload, the size and weight of the payload constrains the size and weight of the structure, which in turn constrains the required power of the engine. There are remote-controlled planes of the size of a pocket calculator. But while the pocket calculator is still useful to calculate, the pocket airplane is just a toy that can't take you, your family and 3 luggage pieces 400 miles out.
It could be done, out of paper and a few pieces of card, but it would have trouble with reverse Polish.
A car from the 1960s could be made for a dollar today. However if you want modern safety features and Technology you're going to have to pay more.
what happens if you divide by zero?
you get an inconsistent result
The memory wire snaps to prevent the breaking of maths.
This is a great question. Today, there are built-in rules to detect division by zero: not allowed. But what if those safeguards didn't exist? What would happen?
It's a fascinating question, and it would depend on the architecture of each calculator. I believe I saw Matt Parker talking about it on one of these videos at some point ... might be time for a little research.
I belive the EC-130 and EC-132 end up in an infinite loop that has to be manually stopped by pressing the CLEAR DISPLAY key to reset.
The universe implodes!
I was wondering how transverse waves would not get stuck where the wire is supported. Torsional or longitudinal waves would not but I only thought of longitudinal not torsional. Brilliant!
Well logic is amazing but how those engineers come up with such ideas, and how the manage to implement them, there are truly talented people in this world.
The polish logician's name should be pronounced as "Yan Wucashievich" in the best approximation
One disadvantage of acoustic memory I would imagine would be any physical impacts causing memory to screw up and get corrupted.
*PLINK PLANK*
Jan Łukasiewicz is pronounced more like "yan wukashevich" (this is still a tiny bit off because polish consonant sounds aren't exactly the same as in english, but close enough)
more like "woo.." similar to "WOOkie"
does plank = 1 and plonk = 0 ??
5:56 Does he knit? (Knitting needles on top left hand corner)
What’s the purpose of sending the information down the piano wire? I get that it delays the information by a few milliseconds... but why? What does the delay accomplish?
Ploonk Plank Ploonk Plank GlGlGlGlgloorrmp is all you needed for your script.
4:15 Yan Wookashevitch. ;)
I'm really interested in that memory. Does anyone know of videos explaining it in more depth?
2 + 3 * 5 - who remembers the old TI adverts about ""real algebraic entry" from the mid-70s
Why does he have a scan of an old German 10DM bank note on the wall? Is there a story behind it, other than that it having a picture of Gauss on it?
so that memory line is basically an audio feedback loop, right?
and the one thing i completely don't get is how the machine recognized the beginning of the stored data when reading from that memory
When I bought my first PC in early 80's I was working in express mail service in central Helsinki. When in a coffee room I told what I'd done everybody asked how could I aford it. I looked around perplexed and asked: "You always brag about buying new cars and no-one asks how you can afford them. When I, who don't even own a driver's license, buy a computer instead of a car you wonder how can I afford it." They went silent.
On same side I was in a public sauna when I heard people talking about maintenance cost of their cars and I told them that my car costs me exactly 7000 FIM (this was before euros). They said that one cannot even get car insurace on that sum so I must be lying. I told them that the year pass for Helsinki public transportation cost 1800 FIM and that leaves 5200 FIM unaccounted for and that is 100 FIM per week for taxi. Then they asked do I spend 100 FIM every week on taxi and I said of course not, but in some week I might use 200 FIM on taxi. So the next question was that if I bought something big and needed to bring home how can I do it in public transportation and I answered that that what the taxi was for. They had no more questions.
Proud to be Polish electronics engineer.
Camera is pointing at the Fridan...”How much is this thing worth?? Where’s a calculator???”
Few people make it till here...
You buried the good part about reverse polish notation (RPN) in an extra video !?? RPN has been used in computers from the 60's (maybe earlier) until today, It is how the calculations like (2 + 3) * 5 are done. Computers solve this like the following: 2, 3, plus, 5, times --- push 2, push 3, add (pop 2 and 3 add them, push the sum(5)), push 5, multiply (pop 5 and another 5, multiply and push the product on the stack) 25 the answer is left on the top of the stack. It is beautiful. Jan Łukasiewicz was born Dec 21, 1878 and invented a similar notation in 1924 (from Wikipedia). Hey Google, Dr. Lukasiewicz deserves a doodle!!
Come on Brady, change the channel pic to tau.
Fite me!
Maybe for some non-mathematical channel?
That would be an *irrational* thing to do
Put a 0 after the 2, then it'd be tau in base pi
Pi is too...
Heh, it's been a while since I last saw a 10DM note
They charged an extra $250 for the square root function.
1:50 my heart skipped a beat lol
The real Doc Brown!
RPN ♥ [ like ] if
polish tip - the polish Ł is pronounced like a W sound not an L sound
So I understand how the bits were represented on that wire, but I still don't understand how they were _stored_ on the wire.
I don't quite understand how that's considered "memory", it sounds more like it's just sending data via vibrations over the wire... But how is that holding onto the data as "memory".
You have to loop it. After the vibration gets to the end of the wire, it is amplified and fed back into the beginning. So the bits are kind of circling through the wire for so long as you need them. The longer the wire, the more bits "fit" onto it.
time to confuse myself when this video comes out of unlisted
Oh no, they made playing cards... I collect playing card decks. Something tells me this is gonna be one of those pieces my collection will never have.
Have you tried division by zero?
" . . . at a used calculator store. Do they even exist?"
it was a joke.....
That's why I quoted it. I found it funny.
Average cost of a new car bought in the US is ~$33,500.00 now.
So... that coil is works as torsion bar?
I wonder if I should make some playing cards for my number-related thing I'm trying to sell.
;)
Plip, plop, plip, plop, splish, splash, splish, splash
He's gonna break it if he keeps it up :D I cringed @1:50