THe mind blowing realization is that the first pulse would trigger the first solenoid at your local exchange to spin around once for each pulse, connecting you to either another local solenoid or a remote one, and then each additional set of pulses would cascade to another solenoid which would connect to somewhere else, until your wires were PHYSICALLY CONNECTED to the wires of the phone you were calling. People used to the Internet and packet routing may not realize that the whole crazy phone exchange was all about making one loop of very long wire between you and your destination.
And that this was true of international calls as well. You would physically link a wire across oceans and continents. This was, of course, also the largest problem as resistances and loss would accumulate rather quickly and calls would get quiet and noise filled.
Thus giving rise to fanciful phone pheaking devices like the "Urine Box" which was designed to send a high voltage pulse through the remote operator's handset.
This wasn't literally the case for most long distance calls. It is more economical to multiplex several calls to share the same physical wires, so the audio and signalling were separated and heterodyned up and down in frequency. The first multiplex route was installed in 1918.
cheers jeff! i have wanted to do this vid for a good few months, running through it on walks talking it to myself, but could only do it when i finally figured out how to make the machine! relieved
I remember making international phone calls from isolated Perth Western Australia to the UK, and the background sounds lent quite an "atmospheric" quality to people's voices. Now I can see what a marvellous setup it was to be able to speak over 12,000 miles of wires, solenoids, repeaters and capacitors without a single soldered joint, spring, gear wheel, electric motor or selector breaking down. Your descriptions, sequences, historical facts, musical creativity, videography and demonstrations are equally mind boggling. A wonderful video, and great followup to *"The History Guy"* video about NOAA "Old Brass Brains" analogue _tidal calculating computer_ which operated for decades until digital computers finally took over.
The rotary memory is a shame it was hidden away for so long buried away in some telco bunker away from being appreciated. That's a beautiful piece of art in motion...Thanks again to expose those amazing mechanisms we just took for granted when siting on the phone waiting to call the other side...
Wow. Thanks, Sam. You beautifully illustrate the insane level of engineering it took to power the humble telephone back in the old days. Your content just gets more and more interesting.
Absolutely brilliant. I am 54 but when I was your age I played with all this stuff. Any bit of electronics I could lay my hand on I would hook it up. I got my mum to type a message on a computer in the garden , hooked up with phone wire via the rs232 port to another computer in my bedroom and I sent a message back. She couldn’t see the point. This was before the internet . Keep up the great work. I love the organ build. You are a guy who can do anything with this stuff.
I remember sneaking the house phone to call friends, when the dial spun back after selecting the number it was the loudest thing known to man. You've brought back a load of happy memories. Also why was 999 the emergency number when it took so long to dial 🤷♂
As I understand, on the old system dialing “0” called the operator, 111 was considered but too risky being dialled by mistake tapping the hang up cradle clearing the line… so 999 was chosen as you could locate the silver stop bar past 0 in the dark, by placing your middle finger in the 0 your index finger automatically dropped into the 9 and could then be used reliably to dial the 9 three times! 😊 I hope that made sense?
My old man was a telephone engineer, took me to a strowger based exchange when I was a kid, the noise was deafening. Before he retired got to see the later computer system which was just a couple of boxes in the corner
I'm so glad you haven't clawed your way back out of the classic telephony rabbit hole yet. Those old phone exchanges sure contained a lot of brilliant electromechanical engineering 😀
Those sounds ring a bell. In the 70s by uncle worked for the GPO (BT) and took us to see a working phone exchange. It was huge room full of machines making sounds like that. There was a backup diesel generator and another room sized lead acid battery for backup. You wouldn't want to fall in the vat of acid.
I've been working with Simon Magpie to use microcontrollers in his pedal that uses the old rotary phone dials. I had made something earlier with an arduino that listened to a rotary phone dial to get numbers. I was sort of surprised when the ones he had had such similar timing to mine. But now that makes total sense. I'm so used to thinking that memory is always available that I never considered the challenges involved in detecting a number back in the day. Really cool!
Its really cool how much of this equipment you've tracked down and gotten running (to whatever degree it still can) Especially with this stuff going the way of the dodo, I had no idea about most of it Super cool and educational
The random "NOISES" in the middle of demonstrating it kind of sums up the whole draw I have to your work. Childlike wonder at the unplanned awesomeness of industrial machinery music. The two-tone warble of two turbine generators almost in sync. How the tones change as you match speed then go a bit further to hear that sound again.
Sir, you're mental and amazing and fun to watch and knowledgeable and a bit of a genius. Thanks for the show and tell. I've spent enough time fiddling with old cameras, so on some level this is pretty close to my heart. Greetings from Germany, keep it up.
As an ex Strowger telephone exchange engineer, the simple explanation of how those switches work was “A op’s (operates) B, op’s CD… and the rest is automatic”. Those pulse-rediallers were commonly used on long distance trunk lines here in the U.K. where there could be a delay in establishing the link with the far end (could be a few seconds) before the end to end link was established so the digits could be received at the far end and the call routed. You can route the output back to the input, and this will just self repeat (up to 40 pulses) so you can make a Christmas tree light flasher/sequencer with multiple pulse repeaters in parallel. Great video as always.
cheers ian, yeah good idea on the christmas tree, i did run it around into itself but i had to think a lot about the pattern to make sure it wouldnt just go back to the simplest pattern, im trying to find another one or so to build a few of these circuits to get them to talk in a circle haha
OMG! I was in the last apprenticeship group that learnt to maintain step-by-step equipment in Australia. I haven't heard the sound of a bi-motional selector in over 30 years, super cool, thankyou.
A long time ago you could run into a phone that had a blank plate instead of a rotary dial that was supposed to be meant for “incoming calls only”… Would blow peoples’ minds when you would just tap out the phone number on the actual hook and make an outgoing call heh.
I was going to make a similar comment. My parents got a phone lock for the rotary phone but it didn't take long to work out you could tap out numbers on the hook, so didn't stop the crank calls we used to make :)
I can’t imagine anyone looking at this without documentation and figuring out what it is or what you were trying to do. You’ve built a lot of crazy stuff but I think This takes the cake for the most incomprehensible contraption in your arsenal. WELL DONE I LOVE IT
electro mechanics is a fantastic world, really a shame that its no longer in use... luckly some people are preserving these amasing inventions and tell other people about them, and use it for other amasing things than what they where designed for. Thanks for taking the time to make the video and share it.
I love this so much! Makes me think this is the language/soundtrack of the telephone system that's playing secretly across the phone lines whenever we make a call. Amazing.
That regenerator is a work of art, and your explanation of it was excellent. I have a lot of respect for the engineers who designed the old telephone equipment, and the technicians who maintained it.
As a ye olde 2-wire kellogg magneto+3V phone enthusiast, I wish I could thumbs up this video over and over. Excellent explanation! It also really gives you some appreciation for the early "RF" transmission line design since a lot of this technology could work at very low voltages (3-6V) over many, many miles even with resistive losses.
I remember, as a lad, opening the phone and squeezing that governor to make the phone dial faster.....can't recall why, but it did work! Great vid, Sam!!
These old electro-mechanical devices are just so fiendishly amazing. Back in the 80's I used to skive off college to the reference section of my local library and discovered Atkinson's telephony books. I used to pore over them for hours on end. This was around the time "System X" was being rolled out and I was the first subscriber to have DTMF dialing (bit of a thing when you're war dialling remote systems to see what answered in an interesting way - before War Games). Interesting times.
Holy god, this is my kind of nerdery. This is glorious. About 20 years ago I took a tour of a telephone exchange here in the northeastern US, and it was an enormous building just filled with thousands of those selector switches (what we see at the 2:00 mark in the video). The sound was so loud and awe-inspiring, that I actually got choked up... it was the sound of human ingenuity just ticking along -- the physical manifestation of people communicating. Most people in their homes were oblivious to how it all worked, and I suppose they had no real reason to know, other than it being cool to know how stuff works. (The Dead Milkmen's most recent Big Questions video sent me here!)
I love the telephone series. The ingenuity of infrastructure engineers in the pre-semiconductor age was simply phenomenal. Also if you’re ever in Seattle, check out the Telephone museum in Georgetown. You’d love it!
When you mentioned dialing using the hook switch, it reminded me of the university where I studied telecommunications. None of the PBX extensions contained a zero as it was reserved for dialing out into the public network. Only a few select phones had the ability to dial a zero (others either had their dial's travel lijited or for those with keys, the zero was removed), the idea being that students shouldn't be allowed to dial out as it was expensive... After learning how phones worked, it didn't take long to figure out that one could dial a zero from any phone just by tapping the hook switch ten times at the right speed!
This is far above and beyond amazing. Brings back so many memories for me of the "good ole days" when engineers truly made the world go round, and how much we take for granted the things that just work. Amazing sir :)
HOLY SHIT I LOVE THIS THING, I'm glad i dont have disposable income since if i did I would spend whatever it would take to make this thing. As simple as it is compared to some of your bigger projects, its unique sound(especially when you record the mechanics of it to, I love that metallic clinking before you hear the synth. Ah! I love it!
I just found 2 of these electromechanical regenerators in a loft of a house I bought, I was finding it very hard to find info on them not knowing what they were other than likely GPO related (found other GPO paperwork), until this video! Awesome work.
I was at the Science Museum of Minnesota (USA,) decades ago, and they showed selector hardware operationally. Was very cool to see how it worked back in the day.
I frickn' LOVE this channel! I recently watched a feature on a 1960s era wurlitzer jukebox.all click and bang. at its heart was a component called the "selection accumulator" essentially a memory to save selections made while one record was playing. electro-mechanical engineering at its fiinest!
You used to get big advertising board things in public places. They'd have a phone on one side and individual buttons to ring local businesses like taxis and restaurants. Anyway, it turns out you could ring any number using the 'flick the hangup switch and count' trick. It was pretty useful, I don't know why they got rid of them.
I used to work on these regens, No1 problem was if any oil got on the pins they had a tendency to fire out and the whole thing would get confused. They were replaced with an electronic plug in replacement that was more reliable and less susceptible to temperature changes. If I remember it was a 1 week course to learn how to adjust them but I never got sent on that course.
It was a 4 day (1/2 day Monday & Friday to allow for travel) course at the Training Centre in Stone here in the U.K. I applied each year, but never got selected during my Strowger maintenance days 🙁
I also worked on regents. I was lucky to go on a course, not at “sunny” Stone but a regional training centre in Leicester. As usual I had been working on these for some time, so it wasn’t to difficult. However 1 person did fail the course, seemed to remember if you couldn’t get it to receive a pulse then send a pulse on all 40 pins, then fail. Bent pins seemed to be the main fault with these. Happy days.
@@willsgrandad bent pins! blimey i bet that took a bit of force, im trying to track down some more to get a loop of the auto auto circuits running, only manated to track down this one and one that has some bits removed. on the hunt! fascinating little things, apparently also they could lock up and become a fire hazard??? is that the case?
@@LOOKMUMNOCOMPUTER All exchange equipment had fuses, so fuse blows before overheating. However can’t remember ever having a hot coil on these. Correct adjustment is paramount . The motor drive uniselectors, which you have shown before,however, where prone to blowing fuses. They put fuses in the test jacks instead of metal links. Can smell burnt coils now! If you go to Bletchley Park, to the computer museum, they have a model of the machine that cracked the enigma code. It is made up of Strowger equipment.
Interesting note : the adverts deemed worthy of this video are : Yve st Laurent Handbags, Velvetine Hot Chocolate AND McCain bag of chips !! At least in my area (Uk). Greetings from Cornwall, home of Pasties and clotted cream.
The human ingenuity never ceases to amaze me. This is some crazy electromechanical monster! Also your ingenuity and willingness to fiddle with this stuff, learning and then sharing with us what you learned about this fine specimen is truly remarkable. Turning this then into a steampunk music machine is the topping and absolute genius! Thank you for doing this. Seriously considering sponsoring you on Patreon.
Pure brilliance - what would those who designed these electromechanical items back in the day have thought? They could not fail to be impressed I am sure!
14:24 Man watching old mechanical switches and devices is just fascinating. To think someone or several people came up with these is just nuts, compared to the simplified electrical chips of today.
This shows the absolute beauty of electro-mechanical engineering and how there were lots of genius solutions that seem really simple in concept and execution but took a lot of time and thought to come to in the first place. I wonder, would you be able to use that memory unit in a jukebox for disk selection?
good old memories seeing that, we all used that tech in Deutsche Telekom even into the early 1990s when i was there learning communication eletronics, think Sam learned more about the old telephone exchange stuff in short time than we at telekom in a year.
That reminds me of my childhood. I spent every afternoon the Mountain Bell offices in Jackson hole Wyoming growing up. My father was a serviceman in the main facility. I hated it when they did their modernization. The new equipment was borring, just sitting there making fan noises. The old equipment was so alive with activity. The silence was disturbing.
I am old enough to remember actively using pulse-dial telephones. In fact, when I was in the US Army, my first active-duty assignment had me working as a military journalist at a location that still did not have touch-tone telephones. I knew that the pulse dial phones worked by 'flashing' the line quickly, but I never knew how the rest of the system made that work. Knowing what I know today through my work as a software engineer, seeing this explains to me why occasionally we might connect to the wrong phone number; anything that relies overmuch on timing is prone to errors. I appreciate even more how well that system worked, despite the occasional wrong number. Gads... could you imagine if we continued to use this system today, with all those phones (particularly all the cell phones), each one requiring all this mechanical stuff?
The motor- driven pulse generator made me think of the Hammond organ tonewheel system. I don't recall any videos of Look Mum No Computer discussing the Hammond, seems right up his alley. Briefly, two of the most interesting qualities of the Hammond 1) ability to proportion individual harmonics 2) unique unequal temperment (because gears and tonewheels have integer tooth counts, harmonic frequencies end up being a collection of sharp and flat, making the sound much richer, in my opinion) Many Hammond organs also included an ingenious vibrato system (different than rotary speaker) wherein a spinning multi-section air gap plate capacitor picks off the signal progressively from an L-C phase shifting line. Brilliant.
Yeah! The ringing machines from exchanges are what the Hammond tonewheel was based on apparently. Search it up. As for a vid on Hammond I do videos on what I can get hold of. Hence none on a Hammond organ like that! Not happenned upon one to dismantle
You clearly work so incredibly hard. You mustn't stop. It was great to visit the museum this summer, I'd love to come again but it's a fair way from Manchester!
In the 'old days', there used to be two bare wires to the house from the telegraph pole. In high winds they would oscillate and the wires could touch... If the emergency number was 111 or 000 the wires could easily 'tap' together nuisance calling the emergency services. Other numbers such as 7's or 8's were reserved for other services. It was also decided 999 was easy to remember and dial in darkness/smoke as it was one finger hole below the '0'. This regenerator was also used as a delay until the equipment was ready to receive the pulses further down the connection.
Amazing simpel and effective device. A 40 impulse FIFO looping stack memory. And since it has the same dial speed and only adds one impulse sequence delay, it can effectively transmit a infinite number of impulse sequences. Genius.
Another time but from the time I grew up when it was the last days of picking up the phone, getting and operator and requesting that they connect you to their party with their patchboard! Well done Sam and making music at the end, intriguing piece with a real sense of ghost in the machine!
the amount of ingenuity that wass put into theses phones to preform a hand full of tasks, communicating being one of them, is hard to grasp when we use silicon and precious metals. the limitations they had to design somethiing that we take for granted is so cool
Just fudging ace Sam! Mental. The biggest puzzle of all is how you fit all this stuff into the same number of hours as we all have to work with?! Cheers man. Lee
Very impressive, never before heard of these diallers restoring the dial pulse timing but very interesting. You mentioned all the signals going over the two wires but you didn't mention the 60 Volt AC bell signal that goes over the same wires. Probably not as relevant to the dialler explanation but still an additional signal over the same wires.
Sam, this video and your channel are simply amazing. You take relay logic to a whole new level with such an elegant hint of wild genius. The explanation of what was clearly a technology to marvel at in its heyday (and again now) really was excellent, although I perhaps only grasped 50% on first viewing input comprehension not output problem ;-). Nicely done Sir.
my neighborhood was JUST forced to switch to 10 digit dialing. we have all had the same area code and first three digits (this is a us number) for decades, and the change has caused a massive problem with the older folks. the phone company gets daily calls that the lines are down because the old folks can't just dial the seven numbers anymore. some of them don't even know the area code because they literally never used it! There was even an older time where you only needed the last four digits to call the other people in this town. oddly enough, the huge company i worked for had their phones set up the same way and dialing just the last 5 digits would get you another internal number. it had to be 5 and not 4 for some reason, but the 1st digit was always the same for every internal number. i also kind of miss lines getting crossed back in the day. it was funny to hear other people talking and to butt in and start shouting stuff at them lol. when cordless phones because super popular, we got a revival of this because your phones would pick up the neighbor's phones and we could shout at them again haha
Over 25 years ago, i saw this telephone connecting relays in live working in an german telecom distribution house with a few thousands working at the same time. immens noise and very impressive.
mesmerizing , the mechanical inginuity is awsome, and to get it all connected into a system is serious cudos. Inspired by your cabinets to buy my dad a lable printer for christmas. Cheers. Bizzarely was just watching a video about a regenerator, in a thermal pump.
There's something surreal about the sudden motions of the programming arm pushing the pins. It's so precise and so quick that the eye can barely track it. Also: is this machine a risk of mangled fingers when powered?
Years ago when you got a motel room there would be a lock on the phone dialer. But if you were clever and could tap out a number with the switch hook tapping out one number at a time like tapping a morse code key ,you could still call out without unlocking the dialer. I can do this and have often shown this to people and friends that have landlines . The phone system still works with rotary phones and you can have fun demonstrating this to friends.
That’s really cool, it reminds me of the record selection system in a 60’s rock ola jukebox I just fixed up for a friend of mine. I wonder which came first, the mechanical jukebox memory or the telephone one.
THe mind blowing realization is that the first pulse would trigger the first solenoid at your local exchange to spin around once for each pulse, connecting you to either another local solenoid or a remote one, and then each additional set of pulses would cascade to another solenoid which would connect to somewhere else, until your wires were PHYSICALLY CONNECTED to the wires of the phone you were calling. People used to the Internet and packet routing may not realize that the whole crazy phone exchange was all about making one loop of very long wire between you and your destination.
And that this was true of international calls as well. You would physically link a wire across oceans and continents. This was, of course, also the largest problem as resistances and loss would accumulate rather quickly and calls would get quiet and noise filled.
Thus giving rise to fanciful phone pheaking devices like the "Urine Box" which was designed to send a high voltage pulse through the remote operator's handset.
Yep. Very complicated, extremely high reliability needed, massive physical infrastructure. That was what was required, so that is what they built.
This wasn't literally the case for most long distance calls. It is more economical to multiplex several calls to share the same physical wires, so the audio and signalling were separated and heterodyned up and down in frequency. The first multiplex route was installed in 1918.
@@Barnaclebeard and yet it was only a hoax
I love that you go through the original built purpose in great detail but then totally take it to the next level.
cheers jeff! i have wanted to do this vid for a good few months, running through it on walks talking it to myself, but could only do it when i finally figured out how to make the machine! relieved
Your content is honestly helping me stay distracted in a most positive way from a hard spot in life. Most sincere thanks.
@@jeff9228 take care jeff hope all is ok
I remember making international phone calls from isolated Perth Western Australia to the UK, and the background sounds lent quite an "atmospheric" quality to people's voices. Now I can see what a marvellous setup it was to be able to speak over 12,000 miles of wires, solenoids, repeaters and capacitors without a single soldered joint, spring, gear wheel, electric motor or selector breaking down.
Your descriptions, sequences, historical facts, musical creativity, videography and demonstrations are equally mind boggling.
A wonderful video, and great followup to *"The History Guy"* video about NOAA "Old Brass Brains" analogue _tidal calculating computer_ which operated for decades until digital computers finally took over.
The rotary memory is a shame it was hidden away for so long buried away in some telco bunker away from being appreciated. That's a beautiful piece of art in motion...Thanks again to expose those amazing mechanisms we just took for granted when siting on the phone waiting to call the other side...
Wow. Thanks, Sam. You beautifully illustrate the insane level of engineering it took to power the humble telephone back in the old days. Your content just gets more and more interesting.
Absolutely brilliant. I am 54 but when I was your age I played with all this stuff. Any bit of electronics I could lay my hand on I would hook it up. I got my mum to type a message on a computer in the garden , hooked up with phone wire via the rs232 port to another computer in my bedroom and I sent a message back. She couldn’t see the point. This was before the internet . Keep up the great work. I love the organ build. You are a guy who can do anything with this stuff.
I remember sneaking the house phone to call friends, when the dial spun back after selecting the number it was the loudest thing known to man. You've brought back a load of happy memories. Also why was 999 the emergency number when it took so long to dial 🤷♂
Its quite hard to misdial 999 on a rotary phone
@@DaveLaneGC True, I would argue its as equally difficult to misdial 888 or 777....etc. They would be quicker to dial
@@roblow8126 They would be quicker indeed but not so easy to do in the dark.
@@evetrue2615 I agree with you. It really should have been 000 or 111. The start or the end of the dial
As I understand, on the old system dialing “0” called the operator, 111 was considered but too risky being dialled by mistake tapping the hang up cradle clearing the line… so 999 was chosen as you could locate the silver stop bar past 0 in the dark, by placing your middle finger in the 0 your index finger automatically dropped into the 9 and could then be used reliably to dial the 9 three times! 😊
I hope that made sense?
You know... just connecting several of those "slow relays" together in loops and nested loops should get you some interesting chaotic behavior.
You sir, are a mad musical genius. Love this channel and cheers mate!
cheers james!
Wow they used to call that the "Click and Bang" system. And he turned it into Tangerine Dream. Good Job! Big thumbs up!
My old man was a telephone engineer, took me to a strowger based exchange when I was a kid, the noise was deafening. Before he retired got to see the later computer system which was just a couple of boxes in the corner
I'm so glad you haven't clawed your way back out of the classic telephony rabbit hole yet. Those old phone exchanges sure contained a lot of brilliant electromechanical engineering 😀
Those sounds ring a bell. In the 70s by uncle worked for the GPO (BT) and took us to see a working phone exchange. It was huge room full of machines making sounds like that. There was a backup diesel generator and another room sized lead acid battery for backup. You wouldn't want to fall in the vat of acid.
Were you ever a teacher? That was a great explanation of how this works. Such a cool idea to make it an instrument. You keep one-upping yourself.
I've been working with Simon Magpie to use microcontrollers in his pedal that uses the old rotary phone dials. I had made something earlier with an arduino that listened to a rotary phone dial to get numbers. I was sort of surprised when the ones he had had such similar timing to mine. But now that makes total sense. I'm so used to thinking that memory is always available that I never considered the challenges involved in detecting a number back in the day. Really cool!
Its really cool how much of this equipment you've tracked down and gotten running (to whatever degree it still can)
Especially with this stuff going the way of the dodo, I had no idea about most of it
Super cool and educational
The random "NOISES" in the middle of demonstrating it kind of sums up the whole draw I have to your work. Childlike wonder at the unplanned awesomeness of industrial machinery music. The two-tone warble of two turbine generators almost in sync. How the tones change as you match speed then go a bit further to hear that sound again.
I love how what was curiosity has turned you into an authority figure on the subject. And I love this topic!
Sir, you're mental and amazing and fun to watch and knowledgeable and a bit of a genius. Thanks for the show and tell. I've spent enough time fiddling with old cameras, so on some level this is pretty close to my heart. Greetings from Germany, keep it up.
As an ex Strowger telephone exchange engineer, the simple explanation of how those switches work was “A op’s (operates) B, op’s CD… and the rest is automatic”.
Those pulse-rediallers were commonly used on long distance trunk lines here in the U.K. where there could be a delay in establishing the link with the far end (could be a few seconds) before the end to end link was established so the digits could be received at the far end and the call routed.
You can route the output back to the input, and this will just self repeat (up to 40 pulses) so you can make a Christmas tree light flasher/sequencer with multiple pulse repeaters in parallel.
Great video as always.
cheers ian, yeah good idea on the christmas tree, i did run it around into itself but i had to think a lot about the pattern to make sure it wouldnt just go back to the simplest pattern, im trying to find another one or so to build a few of these circuits to get them to talk in a circle haha
OMG! I was in the last apprenticeship group that learnt to maintain step-by-step equipment in Australia.
I haven't heard the sound of a bi-motional selector in over 30 years, super cool, thankyou.
Thank you a lot, finally explaining easy enough how the slow and fast relays see when you hung up the call, that's so interesting
A long time ago you could run into a phone that had a blank plate instead of a rotary dial that was supposed to be meant for “incoming calls only”…
Would blow peoples’ minds when you would just tap out the phone number on the actual hook and make an outgoing call heh.
haha hackerman over here! nice
I was going to make a similar comment. My parents got a phone lock for the rotary phone but it didn't take long to work out you could tap out numbers on the hook, so didn't stop the crank calls we used to make :)
I learn to do that after watching Anthony Hopkins do it on Silence of the Lambs, it still works here in my country.,
I remember using an answering machine remote control on these phones, to make a call
Kevin Mitnick did this on the prison phones to make outgoing calls before the judge said he could use that to start WW3
I can’t imagine anyone looking at this without documentation and figuring out what it is or what you were trying to do. You’ve built a lot of crazy stuff but I think This takes the cake for the most incomprehensible contraption in your arsenal. WELL DONE I LOVE IT
electro mechanics is a fantastic world, really a shame that its no longer in use... luckly some people are preserving these amasing inventions and tell other people about them, and use it for other amasing things than what they where designed for.
Thanks for taking the time to make the video and share it.
I love this so much! Makes me think this is the language/soundtrack of the telephone system that's playing secretly across the phone lines whenever we make a call. Amazing.
That regenerator is a work of art, and your explanation of it was excellent. I have a lot of respect for the engineers who designed the old telephone equipment, and the technicians who maintained it.
As a ye olde 2-wire kellogg magneto+3V phone enthusiast, I wish I could thumbs up this video over and over. Excellent explanation! It also really gives you some appreciation for the early "RF" transmission line design since a lot of this technology could work at very low voltages (3-6V) over many, many miles even with resistive losses.
I remember, as a lad, opening the phone and squeezing that governor to make the phone dial faster.....can't recall why, but it did work! Great vid, Sam!!
These old electro-mechanical devices are just so fiendishly amazing. Back in the 80's I used to skive off college to the reference section of my local library and discovered Atkinson's telephony books. I used to pore over them for hours on end. This was around the time "System X" was being rolled out and I was the first subscriber to have DTMF dialing (bit of a thing when you're war dialling remote systems to see what answered in an interesting way - before War Games). Interesting times.
Holy god, this is my kind of nerdery. This is glorious. About 20 years ago I took a tour of a telephone exchange here in the northeastern US, and it was an enormous building just filled with thousands of those selector switches (what we see at the 2:00 mark in the video). The sound was so loud and awe-inspiring, that I actually got choked up... it was the sound of human ingenuity just ticking along -- the physical manifestation of people communicating. Most people in their homes were oblivious to how it all worked, and I suppose they had no real reason to know, other than it being cool to know how stuff works.
(The Dead Milkmen's most recent Big Questions video sent me here!)
Absolutely in love with how the selectors operate, its just so cool!
funky they are indeed
I love the telephone series. The ingenuity of infrastructure engineers in the pre-semiconductor age was simply phenomenal.
Also if you’re ever in Seattle, check out the Telephone museum in Georgetown. You’d love it!
When you mentioned dialing using the hook switch, it reminded me of the university where I studied telecommunications. None of the PBX extensions contained a zero as it was reserved for dialing out into the public network. Only a few select phones had the ability to dial a zero (others either had their dial's travel lijited or for those with keys, the zero was removed), the idea being that students shouldn't be allowed to dial out as it was expensive... After learning how phones worked, it didn't take long to figure out that one could dial a zero from any phone just by tapping the hook switch ten times at the right speed!
This is amazing. Gotta admire the ingenuity of these electromechanical devices. And it is so pleasing to literally see them tick.
17:10 ok, it's been 9 monts now, and I still listen to this. I just LOVE how it's sounds. I feel like it's resonating with my emotions and stuff.
This is far above and beyond amazing. Brings back so many memories for me of the "good ole days" when engineers truly made the world go round, and how much we take for granted the things that just work. Amazing sir :)
EM gear is and always will be astounding!
HOLY SHIT I LOVE THIS THING, I'm glad i dont have disposable income since if i did I would spend whatever it would take to make this thing. As simple as it is compared to some of your bigger projects, its unique sound(especially when you record the mechanics of it to, I love that metallic clinking before you hear the synth. Ah! I love it!
I just found 2 of these electromechanical regenerators in a loft of a house I bought, I was finding it very hard to find info on them not knowing what they were other than likely GPO related (found other GPO paperwork), until this video! Awesome work.
I was at the Science Museum of Minnesota (USA,) decades ago, and they showed selector hardware operationally. Was very cool to see how it worked back in the day.
it's amazing the phone system ever worked at all with all those mechanical pieces being involved.
I frickn' LOVE this channel! I recently watched a feature on a 1960s era wurlitzer jukebox.all click and bang. at its heart was a component called the "selection accumulator" essentially a memory to save selections made while one record was playing. electro-mechanical engineering at its fiinest!
Im always amazed that someone was able to figure these things out.
Thank you, Sam, for showing them to us.
You used to get big advertising board things in public places. They'd have a phone on one side and individual buttons to ring local businesses like taxis and restaurants. Anyway, it turns out you could ring any number using the 'flick the hangup switch and count' trick. It was pretty useful, I don't know why they got rid of them.
The ambient music that your play at the end of the video is wonderful stuff. I could listen to it for hours on end. Clever stuff!
I used to work on these regens, No1 problem was if any oil got on the pins they had a tendency to fire out and the whole thing would get confused. They were replaced with an electronic plug in replacement that was more reliable and less susceptible to temperature changes. If I remember it was a 1 week course to learn how to adjust them but I never got sent on that course.
It was a 4 day (1/2 day Monday & Friday to allow for travel) course at the Training Centre in Stone here in the U.K. I applied each year, but never got selected during my Strowger maintenance days 🙁
I also worked on regents. I was lucky to go on a course, not at “sunny” Stone but a regional training centre in Leicester. As usual I had been working on these for some time, so it wasn’t to difficult. However 1 person did fail the course, seemed to remember if you couldn’t get it to receive a pulse then send a pulse on all 40 pins, then fail. Bent pins seemed to be the main fault with these. Happy days.
@@willsgrandad bent pins! blimey i bet that took a bit of force, im trying to track down some more to get a loop of the auto auto circuits running, only manated to track down this one and one that has some bits removed. on the hunt! fascinating little things, apparently also they could lock up and become a fire hazard??? is that the case?
@@LOOKMUMNOCOMPUTER
All exchange equipment had fuses, so fuse blows before overheating. However can’t remember ever having a hot coil on these. Correct adjustment is paramount .
The motor drive uniselectors, which you have shown before,however, where prone to blowing fuses. They put fuses in the test jacks instead of metal links. Can smell burnt coils now!
If you go to Bletchley Park, to the computer museum, they have a model of the machine that cracked the enigma code. It is made up of Strowger equipment.
Interesting note : the adverts deemed worthy of this video are : Yve st Laurent Handbags, Velvetine Hot Chocolate AND McCain bag of chips !! At least in my area (Uk). Greetings from Cornwall, home of Pasties and clotted cream.
The human ingenuity never ceases to amaze me. This is some crazy electromechanical monster! Also your ingenuity and willingness to fiddle with this stuff, learning and then sharing with us what you learned about this fine specimen is truly remarkable.
Turning this then into a steampunk music machine is the topping and absolute genius!
Thank you for doing this. Seriously considering sponsoring you on Patreon.
Sam you seem to know exactly what you're doing and I feel really fortunate to be along for the ride
Every time I watch one of your videos, it amazes me how much you know, but it's even more amazing that someone invented it in the first place.
I'm just regurgitating facts the people that made this are the smart ones! Like you say!
@@LOOKMUMNOCOMPUTER But to retain the facts and implement them is quite a feat.
@@agomodern I agree with that. He underestimates his intelligence! I would be lying if I said I REALLY understood half of the content he puts out!!
Pure brilliance - what would those who designed these electromechanical items back in the day have thought? They could not fail to be impressed I am sure!
14:24 Man watching old mechanical switches and devices is just fascinating. To think someone or several people came up with these is just nuts, compared to the simplified electrical chips of today.
This shows the absolute beauty of electro-mechanical engineering and how there were lots of genius solutions that seem really simple in concept and execution but took a lot of time and thought to come to in the first place. I wonder, would you be able to use that memory unit in a jukebox for disk selection?
Fabulous ! Takes me back to the old days working in Strowger exchanges in the 70s! Thanks, Sam!
As nuts as ever! It never ceases to amaze me what can be done and has been done with relays.
Love this musical steam-punk Edison, a true educator of pre-Digital history putting the lights on truly fascinating bits with fun remaining primary!
The sound of this is really haunting. Reminds me of stuf Delia Derbyshire did for BBC science programmes
good old memories seeing that, we all used that tech in Deutsche Telekom even into the early 1990s when i was there learning communication eletronics, think Sam learned more about the old telephone exchange stuff in short time than we at telekom in a year.
That reminds me of my childhood. I spent every afternoon the Mountain Bell offices in Jackson hole Wyoming growing up. My father was a serviceman in the main facility. I hated it when they did their modernization. The new equipment was borring, just sitting there making fan noises. The old equipment was so alive with activity. The silence was disturbing.
I am old enough to remember actively using pulse-dial telephones. In fact, when I was in the US Army, my first active-duty assignment had me working as a military journalist at a location that still did not have touch-tone telephones. I knew that the pulse dial phones worked by 'flashing' the line quickly, but I never knew how the rest of the system made that work. Knowing what I know today through my work as a software engineer, seeing this explains to me why occasionally we might connect to the wrong phone number; anything that relies overmuch on timing is prone to errors. I appreciate even more how well that system worked, despite the occasional wrong number. Gads... could you imagine if we continued to use this system today, with all those phones (particularly all the cell phones), each one requiring all this mechanical stuff?
You should do a video of the "Close Encounters of the 3rd kind" tone sequence on this thing as a Short.
The motor- driven pulse generator made me think of the Hammond organ tonewheel system.
I don't recall any videos of Look Mum No Computer discussing the Hammond, seems right up his alley.
Briefly, two of the most interesting qualities of the Hammond 1) ability to proportion individual harmonics 2) unique unequal temperment (because gears and tonewheels have integer tooth counts, harmonic frequencies end up being a collection of sharp and flat, making the sound much richer, in my opinion)
Many Hammond organs also included an ingenious vibrato system (different than rotary speaker) wherein a spinning multi-section air gap plate capacitor picks off the signal progressively from an L-C phase shifting line. Brilliant.
Yeah! The ringing machines from exchanges are what the Hammond tonewheel was based on apparently. Search it up. As for a vid on Hammond I do videos on what I can get hold of. Hence none on a Hammond organ like that! Not happenned upon one to dismantle
You clearly work so incredibly hard. You mustn't stop.
It was great to visit the museum this summer, I'd love to come again but it's a fair way from Manchester!
Always wondered how that works... thank you for explaining!
In the 'old days', there used to be two bare wires to the house from the telegraph pole. In high winds they would oscillate and the wires could touch... If the emergency number was 111 or 000 the wires could easily 'tap' together nuisance calling the emergency services. Other numbers such as 7's or 8's were reserved for other services. It was also decided 999 was easy to remember and dial in darkness/smoke as it was one finger hole below the '0'. This regenerator was also used as a delay until the equipment was ready to receive the pulses further down the connection.
The combined sounds of the synth and mechanical bits are what make it great.
Music you’ve made with this thing is mesmerising and charming. Well done!
Your content has been brilliant lately! Keep at it!
Very educational with a lot of well focused close up shots of the mechanisms, this is premium quality! And there are nice Hainbach vibes at the end :)
This is an amazing video. Aside from the really interesting knowledge you're sharing, the lighting and camera work are top tier. Great job!
Amazing simpel and effective device.
A 40 impulse FIFO looping stack memory.
And since it has the same dial speed and only adds one impulse sequence delay,
it can effectively transmit a infinite number of impulse sequences. Genius.
i actually find this really interesting, i'm always fascinated by by mechanical old things that do simple things in complex ways.
Another time but from the time I grew up when it was the last days of picking up the phone, getting and operator and requesting that they connect you to their party with their patchboard! Well done Sam and making music at the end, intriguing piece with a real sense of ghost in the machine!
Absolutely great, and I love the sounds the machine makes.
Its crazy how old stuff required so much thought and ingenuity to create a solution to a problem and now its pretty much just circuit boards and code.
I can see the song at the end being used as some kind of sci-fi alien language. I love it
This was a great episode. Loved the obscure electomech, explanation, and sounds.
the amount of ingenuity that wass put into theses phones to preform a hand full of tasks, communicating being one of them, is hard to grasp when we use silicon and precious metals. the limitations they had to design somethiing that we take for granted is so cool
Just fudging ace Sam! Mental. The biggest puzzle of all is how you fit all this stuff into the same number of hours as we all have to work with?! Cheers man. Lee
ok, This is seriously the coolest device you've shown on the channel
The wonderful world of human engineering. You are a magician. Thank you for this work of memory.
Very impressive, never before heard of these diallers restoring the dial pulse timing but very interesting. You mentioned all the signals going over the two wires but you didn't mention the 60 Volt AC bell signal that goes over the same wires. Probably not as relevant to the dialler explanation but still an additional signal over the same wires.
Sam, this video and your channel are simply amazing. You take relay logic to a whole new level with such an elegant hint of wild genius. The explanation of what was clearly a technology to marvel at in its heyday (and again now) really was excellent, although I perhaps only grasped 50% on first viewing input comprehension not output problem ;-). Nicely done Sir.
I love this fusion of telecom and music making so much!
Looks like the machine ET used to call home - but cool.
Love it!
my neighborhood was JUST forced to switch to 10 digit dialing. we have all had the same area code and first three digits (this is a us number) for decades, and the change has caused a massive problem with the older folks. the phone company gets daily calls that the lines are down because the old folks can't just dial the seven numbers anymore. some of them don't even know the area code because they literally never used it! There was even an older time where you only needed the last four digits to call the other people in this town. oddly enough, the huge company i worked for had their phones set up the same way and dialing just the last 5 digits would get you another internal number. it had to be 5 and not 4 for some reason, but the 1st digit was always the same for every internal number.
i also kind of miss lines getting crossed back in the day. it was funny to hear other people talking and to butt in and start shouting stuff at them lol. when cordless phones because super popular, we got a revival of this because your phones would pick up the neighbor's phones and we could shout at them again haha
Wow... a mechanical ring buffer. Interesing concept!
Really puts a new (or old) spin on the term "ring buffer"
Over 25 years ago, i saw this telephone connecting relays in live working in an german telecom distribution house with a few thousands working at the same time. immens noise and very impressive.
relays are one of my favorite percussion instruments.
mesmerizing , the mechanical inginuity is awsome, and to get it all connected into a system is serious cudos. Inspired by your cabinets to buy my dad a lable printer for christmas. Cheers. Bizzarely was just watching a video about a regenerator, in a thermal pump.
huh...I guess I never understood why they were called relays until now....this vid is PACKED full of info!
I think Tommy Flowers (True British Hero) would enjoy what you have created and continue to create!
There's something surreal about the sudden motions of the programming arm pushing the pins. It's so precise and so quick that the eye can barely track it. Also: is this machine a risk of mangled fingers when powered?
Years ago when you got a motel room there would be a lock on the phone dialer. But if you were clever and could tap out a number with the switch hook tapping out one number at a time like tapping a morse code key ,you could still call out without unlocking the dialer. I can do this and have often shown this to people and friends that have landlines . The phone system still works with rotary phones and you can have fun demonstrating this to friends.
saw the insides of a gas/petrol pump today while it was getting serviced - thought of you. It was gnarly!
You should do a video on sound powered telephones. It's basically witchcraft.
Great bit o' kit there! Retro-future-steampunk thing going there. Awesome.
That’s really cool, it reminds me of the record selection system in a 60’s rock ola jukebox I just fixed up for a friend of mine. I wonder which came first, the mechanical jukebox memory or the telephone one.