IBM Selectric Typewriter & its digital to analogue converter 

that must've been expensive if broke

@@alexradu1921 metal ball, carpeted typing lab. Still makes me laugh when I think about it!

Had me a good laugh. Thanks!

​@@markk3652plastic ball with silver-coloured plating on top. I serviced them.

​@@alexradu1921This was in the 80's, so planned obsolescence wasn't in full effect yet.

So violence is amazing?

+Harald Jan Dahle Isn't it? We watch violence every day after way. If not amazing it is quite entertaining.

@@petrofilmeurope wow you really got them didnt you

@@VineFynn some people are so stupid they only took one word out of a sentence

Another slow mo in the original very cool commercial: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-vNUEUth7qjc.html "Commercial for IBM's Selectric Typewriter 1960's"

flurng while I understand your argument I think with that argument you could say, that even today there are no real binary to analog converters. When we convert binary to „analog“ we take discrete binary numbers an turn them into other discrete numbers. The resulting numbers are considered „analog“ when the gaps between them are small enough so we can just neglect them. In your example one could certainly build a decent mechanical device that converts digital numbers to 0.000, 0.001, 0.002 etc. and you would sooner or later reach 1.643 and also 2.145 with that. We would consider this output as analog, nevertheless its rather „pseudoanalog“. The gaps are just 0.001 sized instead of 1. Turns out there is no such device that could generate a real analog signal out of a discrete digital one. A D/A converter is in fact a function f that transforms a number into an other number. For a given (digital) input number we want only one possible result as output, everything else would result in nonsense. That means we want the f to be injective. Now since the input is discrete and finite (there is a maximum digital number that a computer can store) we can not use f to generate an continuous output set out of the input. Since the continuous output has an infinite amount of numbers between every two numbers of that set, we would simply run out of input numbers before we could „hit“ every possible output.

@@schievel6047 interesting point. However, 'time' can be used to bring continuity in the output space. For example, an inverter working with a DC 12 Volt battery can give a close to sinusoidally varying output using clever 'circuit switching' electronics.

Well, it turns out that reality is fundamentally discrete, not continuous, so really digital vs. analog is a question of the resolution of a system vs. the resolution of its measurement.

@@schievel6047 how you discuss such an complex technical or niche topic with such a fluency...think we have a core techie in comment section....nice to see you people around.

@@stallio5612 oh thank you very very much. I really appreciate your compliment because English is not my mother tongue and I am always worried when I try to discuss a math topic in English people only under nonsense 😅

every video i feel the same, i want to be an engineer and it has made me more insecure for sure

134513 1435 Haha same my dude

It was a different time, hundreds of times less distractions, more commitment, less arrogance, less ego. People worked harder, longer, smarter and for others, not for themselves. Check out "my dinner with Andre"

@@fnytnqsladcgqlefzcqxlzlcgj9220 na man they were bored as fuck

@@agustinsida8877 baka

"So old"

thank you dankpods guy for pointing to Alec Technology Connections that brought me to this channel, fascinating engineering indeed!

Yep me too. I can still hear the sound of my Mom chopping away on her Selectric back in the 70's.

And yet your username has "chemtrail" in it... your family went off the deep end apparently.

@@audilicous it's so myopic of you to interpret it like that - in fact it's clear from the guy's username and videos, that it's the opposite of what you wrote

@@audilicous I think he's being sarcastic with the name, also, it isn't only dumb people fall for conspiracies, some people are smart, know they're smart and so, want to think differently to others (subconsciously) and so they are more likely to fall for things that are believable.

@@ChrisOReilly Chemtrails are real. The conspiracy is trying to hide the truths about them.

@@artsmith103 I have been in the cockpit of commercial jets a number of times and no switch causes "chemtrails", it's the stupidest idea I've ever heard.

The only cable in the selectric is the one that moves the carriage! Tilt and rotate are translated to the hall via thin metal tapes that go around pulleys out of frame, and what the video calls cables are in fact metal rods!

Your Underwood STILL ISN'T completely obsolete.

Your Underwood #5 will still work even if there’s a power cut. The Selectric, however, will not. Progress?

@@hazelanderson1479 Exactly. I wish I could upvote that comment about five times. 8)

@@suprememasteroftheuniverse Not sure if using an ink ribbon more than once is worth the savings compared to the outcome. 😉

@@hazelanderson1479 But who's going to type in the dark, anyway.

That was Fun to imagine

That was only because the selectric was out of adjustment.

I remember being a kid in the early 90s and trying to type really fast on a Brother electric typewriter, to my astonishment it had some kind of buffer so it behaved exactly like that, when I overrun the mechanism it would continue typing as I stopped my key strokes. I remember taking it apart just to have a look, it was rocket science for me haha

Wow

Considering this thing can type 14.8 characters per second, and the average amount of letters in a word is 6.7(lets say 7 for caution); to get a result of 10 additional seconds of typing once stopped, she would need to type at 127 words per minute PLUS an additional 21 words per minute for a whole minute to result in 10 seconds of continued letter input. This is 148 words per minute which hard to believe.

I was trained on Selectric repair and maintenance back in 1978. We were told that the inventors of the Selectric 1 went insane because the mechanism was so complex. Do you think that there is any truth to that rumor?

@@MichaelHutton1 lol, nope none at all. He retired as a vp in the 80s, had a horse farm and had very thought provoking questions for his grandchildren. Good man.

@@Greenskycity thanks. It’s nice to finally get such information even 44 years later.

That's so cool! ⌨️📝 Get it? Type write(r)! 😁

Don't be. It was wrong anyway.

@@timhofstetter5654 [citation needed]

@@Number_055 Mo citation actually necessary. There's nothing analog about the IBM Selectric; it's purely mechanical-digital (base 4 and base 22). The whole premise upon which this video was based was incorrect.

@@timhofstetter5654 It uses discrete analog output. Mechanical levers by nature are analog.

@@darkwood777 Neither of those statements even begins to be true. Mechanical levers with a finite number of orientations / positions are by nature digital. Your fingers are levers, and they are the prime origin of the term "digital". When you count on your fingers, they have two positions: up (1) and down (0). There is no "halfway" (~0.5) position. There is no one-third (1/3) position. There is nothing analog about your fingers when you're counting. Anything with a finite range of positions is digital. Analog is infinitely variable with or without optional limits.

Wow! Fantastic!

en.wikipedia.org/wiki/IBM_Selectric_typewriter#Use_as_a_computer_terminal

saa82vik It existed in 71 or 72, it consisted of 5x8” magnetic card that was inserted into a writer/reader. I can’t recall if the Selectric itself was able to store part of the document until it was transcribed on to the magnetic card.

I built one, in 1983. It hooked up to an Apple ][ using a parallel (8 bit) output card. The challenge was writing the driver in 255 bytes.

@@matthewlitvak2695 You are referring to one of the Mag Card machines (there was an original Mag Card, and then a Mag Card II), based on the same system of reed relays and solenoids. But IBM also had computer terminals based on the Selectric. The Mag Card had a separate console handling all the electronics but was not connected to a computer. The IBM Memory Typewriter put the entire system within an enclosure just a little larger than a regular Selectric.

@@ErikBruchez I’ve got a very vague memory of the entire system, I was 10 or 11 when it came out in 72. It was initially kept in the file room at my dads law firm in Chicago. I remember the card holder and the reader, I just can’t remember how it operated and whether you could edit a stored document.

Why?

We were sent from a typographically smooth youtuber named Alec from Technology Connections.

Also used in the "Selectric" article on English Wikipedia.

yeah! I want to learn more about how this level of accuracy is sustained I'm sure after a minimum of a crazy number of keystrokes expected in its lifetime!

August 6th for me! 📆

You still here?