Great video Sarah, i love to see you tell how the old network worked, it could be fun to see you make some videos with evan doorbell, i think you two could make some very interesting videos together 😉😊
"through the magic of having two of them" is a very direct reference and I love it. If Sarah decided to watch and copy his style a bit, I'd say it's definitely a good thing.
You are so good at putting across information in a clear way. I only recently discovered your videos and intend to spend time watching more. I used to be a telephone technician in both step by step and crossbar exchanges in Australia until I transferred into the airline industry. Now I am retired, your videos are bringing back so many memories. Thank you.
As a retired 40+ years CO Tech (Switchman) I enjoy watching your knowable talks about the CO, it brings fond memories of my working years. Do you have a video that explains why the CO 48 volt battery, positive is grounded? That might be of interest to your viewers.
As a retired SxS switchman for SouthwesternBell in the 70's, I can't wait for the next video. These bring back alot of memories. Namely a very fulfilling career. Thank you so much.
THANK YOU, Maestro! I can claim to fame as 1 individual Data point in Bell's decision to change 0 from Information to Directory Assistance. kid at 7 whips the dial all the way around, fingertip stuck next to the 0 and lets go. rng rng ring "Information" "Hi, how are you today? How many Teaspoons are in a Tablespoon, please?" "There are three Teaspoons in a Tablespoon, young person. Have a great day." also, I deciphered the dialer and tested it. I could successfully 'dial' any number by tapping the hang-up button, technical term long forgotten. I learned everything I needed to know about everything, taking a bedside Westclox wind-up alarm clock, with no intention of putting it back together, just like science does. "The gears is what I was after. Aside from the sharp ends on their shafts pricking my little six year-old fingertips. Tiny spinning tops. Thank You!
I don't know how I rabbit holes into your video at 4:30am on a sleepless night, but as someone who was obsessed with the 2600 magazine (even more so the very fact they were sorta hidden at my Barnes & noble) I absolutely love your channel and am so excited that I basically just found a new channel to binge. Thank you for making this content. ❤
I can’t get enough of your videos, Sarah! Not only do you know your stuff, but you’re excellent at CONVEYING that info, while keeping it interesting. Looking forward to the next installment!
The 5 ESS uses the High Level Service Circuit which can generate any ringing voltage plus any coin phone control voltage. It is a four quadrant voltage source completely under software control. Output was +/- 200V. If a power surge came in during ringing, it would convert it to DC and charge the office battery. IIRC, it is the TN848, but it has been a long time.
Great job Sarah. I started my telephone career in 1965 as a Western Electric installer. My first assignment was the M&T building in Nashville, Tn. The ringing and tone generators were kept in the basement.
I started my career with West Electric, February 1963, retired after 36 years service. Today is, 9 11 2022. The worst day in our history I lost three friends in the North Tower. Made all the people that perished on that horrible day rest in peace.
"Ring Off" Love the postcard proudly displayed on your switchboard at 5:42 Excellent presentation, more please. I was in Vietnam we use magneto field phones and switchboards, no one rang off so the gruff sounding male operator operator would brake in into the phone conversation saying "working" and if you didn't answer working working, quickly he would break down the line.
Great Video. When you make the next video about the ringing generator, tell them that the ringing cycle was three seconds long. It was divided into three groups. Each group would ring for one second in sequence. This way the generator only had to power one third of the ringing phones at a time.
In the Marines, we had TA-1 phones with the same functional magneto to ring a point to point connection. It was often used to shock the heck out of another Marine, though.
I often watch videos on the channel, they are very interesting, this one is now a very good summary one of the early telecommunication technologies. Anyway, I think I can say on behalf of many of us, thank you so much for keeping these machines and for them to be seen in operation by those who didn’t even live when they were in their heyday.
Cool. A WECO 317 wall phone. As a retired Bellhead, I was glad to find a WECO 317 at a rural garage sale. It had all its internals including the magneto and two tired talking batteries!!
Sarah, great explanation. BTW United Telephone, Independent Telcos used different frequencies on party lines like 16 2/3 Hz 20, 25 and 30 Hz. Subscriber phones had frequency “tuned” bells to respond appropriately. Bell system didn’t adopt that scheme however. Bell used a distinctive ringing like two longs and a short or tip vs ring to ground on two party lines. Who knew!
Great job keep up the work you're doing your educating me and I had 36 years with the company, West electric and AT&T. I never was involved with the power system I was more into the switching systems, but many things you had mentioned I was totally unaware of. As a retiree for a number of years now I'm still learning about how various systems within the system worked. You doing a great job keep it up for all us retired employees. When I look at the older equipment it brings back very fine memories God bless you stay safe keep doing what you're doing you're educating the world actually.
Been running a PBX for 10 years now, trained by an old head from MST&T who cut his teeth working SxS and Crossbar, and helped see us through to the age of SIP. He imparted a wealth of knowledge and a love of telephone systems to me, and finding this channel is just so great getting to see all of this stuff actually working.
"Through the magic of having two of them." Lol love the Technology Connections reference there, and I loved this presentation! So informative and easy to follow. Glad this channel has started showing up in my recs!
Thanks again for this great info. Looking at the larger ringing plant at the end of your video, I recognize the GE motor used for the AC motor in that setup. It looks almost exactly like the Western Electric branded GE motor in my 1925 BF Sturtevant workshop fan.
Thanks Sarah! I thoroughly enjoyed that and look forward to the next installments. Your enthusiasm and passion show through and it is great to see how comfortable you have become in front of the camera.
I worked for Southern Bell Telephone in Ft. Lauderdale, Fl. 1969-1983 I/R Switching Tech and Special Services. Cleaned the drums on ringing machines many times. Cool Museum
Stumbling upon this video has been a delightful turn in my quest to delve into the workings of rotary dial phones, particularly as I aim to construct supporting circuitry to transform an old rotary dial phone into an engaging conversation piece at my workplace. The clarity and ease with which you elucidate the theory of operation are truly captivating, showcasing your exceptional talent for making complex concepts accessible. It's evident that you've invested considerable thought and effort into creating this content, and for that, I extend my heartfelt gratitude. Your video has earned a like and a new subscriber in me, and I eagerly anticipate exploring the rest of your channel's offerings. Excellent work!
I had been curious about this topic and your video was suggested by the TH-cam algorithm. So glad it was! Very educational, organized presentation and it is obvious your knowledge on the topic is exceptional. Educational and entertaining video. Excellent work.
I never really thought about how complicated the old telephone system was. And how ingenious! It seems pretty wild that this stuff was hand built at one point, too.
Condensed and informative videos on a complex technology that most of us have grown up with and completely take for granted. I remember as a teenager being able to push a combination of buttons or jiggle the receiver hang up switch and voila....access to a party line. Thanks for the passion in this technology and making the videos.
In my small home town, we moved just "out of town" when I was 6, about 1954, into the house Dad and Gramps had built before WWII. The phone was still a wall mount hand crank "Farm" / country/ party line, with more than 20 customers. Our number was 19F4 which meant we were the 19th customer on the "Farm" line and our ring was "fast 4" or 4 short rings.
Love this series. Such clear and illustrated programs. I built switchboards for Stromberg-Carlson in mid-1950s. You’ve put together a wonderful history of phone technology. Thanks for keeping it alive.
I'm going to be 100% honest here because that's me...I really found you to be odd and slightly offputting when I first saw you in a video. That said, you are one really knowledgeable individual. I find your information to be extremely concise and well layed-out. I like the tone and cadence of your delivery. You made me a fan. It's all your fault! 😆
Very cool, and very helpful! I recently acquired a couple of 1950ish magneto phones, which I intend to wire up as an intercom. A lot of folks who've written up docs on using phones wired locally as intercoms lament that they don't have the devices needed to make the phones ring, and seeing this explanation reassures me that having the magnetos will sidestep that.
Every time I think the production quality of your presentations has peaked, I'm proven wrong. Great work - looking forward to the next installments!
2 ปีที่แล้ว +8
Absolutely wonderful! Can't wait for the next video. Where else will you find videos with people excited at describing ringing generators and tone plants!
Sarah, this is so freaking cool! I've learned so much from this video and it makes me so excited to hopefully be a part of preserving history at this museum someday!
Perhaps an in-depth topic for one of your videos regarding ringing: multiline business phones from the 1960s-80s (1A2 phones) often had single gong bells that only responded to 1/2 of the AC wave. If you put a diode in series with the bell, it would either ring normally, or not at all, depending on which side of the AC wave it blocked. This came up because with these phones, ring voltage was provided on a dedicated wire pair, separate from the tip/ring pairs from the telco, and ringing was "programmed" by the installer, to control which incoming lines rang which extensions on the multiline sets. A diode matrix block was used to control this, one diode per line per extension. The diode matrix managed a locally provided 30Hz ring voltage that was usually a small AC "frequency generator" (often a Western Electric 118a, or sometimes larger KSU supplies) that divided down the 60Hz to 30Hz using a special phase shifting transformer. I remember wondering why the presence of the diode matrix didn't affect the loudness of ringing in these phones, but soon came to realize that the bells in these phones only rang on 1/2 of the AC wave anyway, with or without the diodes. To use diode matrix ringing, the ring capacitor in series with bell in each phone set had to be bypassed, and the installer had to get the polarity of the diodes right, otherwise the bells wouldn't ring at all. The bells actually have a red and black wire, and if you accidentally switch them, the bells won't ring if a diode matrix is used to control extension ringing, as they really did /nothing/ if the wrong side of the AC wave was blocked by the diodes.
You're a great educator and communicator. Thanks for the great video. Not only do you describe how the magneto works, you give great examples of how it was used. I really appreciate your videos! Thanks, and be well!
In some ways, a central battery, POTS phone line is more reliable than digital IP phone service. If your power goes out, the phone still works, unlike your IP phone, which goes dead when your network goes down.
Yep, I run a PBX, so mostly H.323 and SIP IP endpoints/signalling. But we have a fair share of analog going on for lots of longer runs and fax/data. Nice to get a taste of the old school with the analog stuff.
Hi Sarah This brings back a lot of memories of my days at Cincinnati Bell back in the 50's and 60's when we all studied the old principles. A lot of what you are describing goes back further but I still have the old books that I was given back then. I watch all your videos and find them very well put together. I hope to get out there late this year and visit the museum. Steve
Nice to see you back! Great episode and lovely antique tech, because what else would I expect from you? Goofing off for a while? Yeah, that's cute too. Missing Astrid a bit :) By the way, I got an idea of connecting (probably by VoIP) the Connections Museum with Sam Battle's one (Look Mum No Computer / This Museum Is Not Obsolete). Would be cool to call each other, and even cooler to set up a trunk connection :)
You have an excellent presentation style. Not too dry and not too "over the top." Very cool to see younger generations knowing how the "electromechanical world" used to work :) Oh and LOVE the mention of phone phreaks :) Evan Doorbell would be proud!
The ringtone as I remembered was 109 volts, the ring generator was down with the power supply for the communication systems. All the wet cell batteries will link together either 24 or 48 volts. I am not a power expert but I am an expert in electronics switching number one number four number five, tsps and ETS systems, 36 years, working for Western Electric, AT&T, qualified system specialist. In all of the above. Today's date 9/11/2022, the worst day in our history. Make all those that lost their lives rest in peace.
I only got the 10c spiel on ring generators, I've mostly done wireless cell/MTSO. It probably varies depending on generation of equipment, manufacturer etc. The ring voltage was a doubling of whatever the DC plant voltage was. A 48v plant is almost never running at 48 volts. Primarily, at least in smaller plants the manufacturer's specified float voltage range for the batteries dictates how the voltage is set. Plus you figure in voltage drop between the DC plant and the ring generators but that should be small. So you can see 49 and change to 56 volts at the plant. Typically 52 (ish) volts. I know I've come across 110v ring voltage, it hurt.
Just came across your channel. Very good info. FWIW, you are aware that the spring between the motor and the magneto at 9:33 is to align the two different shafts so there is no misalignment and take up shock between the 2.
I just discovered and subscribe to your channel and I'm totally addicted on the first video! I am an IT engineer retired and have always been fascinated by anything with mechanisms that are associated with everyday things like the telephone so keep up the great work, your videos will be viewed by thousands of thousands of people for instruction in the future.
They're often called ignition batteries. Early cars ran their ignition systems off of them. Four wired in series make 6 Volts, just right to excite the ignition coils of a car. Ford changed things when he decided to run his model T from a magneto instead, to avoid reliance on batteries that could go dead at inconvenient times. The batteries could be saved for just starting, instead. Also, when I went to school, we used them frequently in our science labs.
I was always told it was 80 vac half wave, in other words 80 volts DC turned on and off at 60 hertz. I used to install phone systems for a telephone company in the 1980's. All the literature I ever read at that time said 80 vac half wave for the ring voltage and 48 vdc, We had one customer too far from the switching stations, who had multiple phones in there HUGE "mini" mansion style home. The phone line could NOT ring all the phones nor could it enough current for voice if multiple phones were picked up. Using a few transformers rectifiers and relays we created a mini switching station, when a phone was lifted within the house, the 48vdc generated by a transformer, bridge rectifier, a few capacitors, one 150 ohm resistor and a relay with a 150ohm coil, would connect the house hold phones to a transformer for voice, and connect the telephone line to the secondary of the phone line. Ring current for from the telephone line, would activate a relay instead of a bell, and the relay would in turn supply 80 vac half wave to the house hold system which in turn rang the the telephones through out the house. Since the voice signal was passed through a 1:1 transformer, the signal was lower than usual, but was still completely audible.
This is one of the most comprehensive & easy to understand explainer about telephones I ever seen. I really love your presenting style, like a modern version of Tim Hunkin (look him up if you haven't heard of him).
This is the coolest personality i've ever come across on a tech channel... you had me at the coupler sound-effects but I Dream of Jeannie clinched it. Subscribed. :)
Thanks for a great video. You're a natural instructor. Of course modern technology performs light years ahead of this old school stuff. Though the minds that built this cutting edge technology of a century ago, deserve respect. As well, the craftmanship of yesterday often surpasses modern build quality.
Thanks for the very informative video. I'd heard the phrase "Ring off" before but never understood its origin. I find the evolution of technology quite fascinating and the creative ways that problems were overcome.
The ring voltage was a small workplace "hazard" for those that worked on telco equipment. It was a spicy reminder if you touched connections while ring voltage was present.
Great job Sarah, Your knowledge of the phone system is phenomenal! You have a very understandable presentation of the subject. Keep up the great videos.
Ok omfg.... I've "known how it all works" since a curious kid 30 years ago but holy shit you just made it all click with regards to how our phone being "off the hook" closed the circuit allowing it to reach the CO... OMG FINALLY after decades it actually clicks in my brain. THANK YOU
Amazing, I've always wondered if there is more to the phrase "Ring Off", even dictionaries skip the history and say it's just something people say at the end of a call. Thank you for solving this mystery.
Like the technology connections style presentation, don't know if it was intended or not but great stuff either way!
I believe Sarah is, professionally, a teacher, so the style seems likely intentional. I love it as well -- always love a good history lesson :)
"through the magic of having two of them...." most definitely an homage
Great video Sarah, i love to see you tell how the old network worked, it could be fun to see you make some videos with evan doorbell, i think you two could make some very interesting videos together 😉😊
"through the magic of having two of them" is a very direct reference and I love it. If Sarah decided to watch and copy his style a bit, I'd say it's definitely a good thing.
3:38 Is that an homage to our friend Technology Connections? Either way, I love it.
You are so good at putting across information in a clear way. I only recently discovered your videos and intend to spend time watching more. I used to be a telephone technician in both step by step and crossbar exchanges in Australia until I transferred into the airline industry. Now I am retired, your videos are bringing back so many memories. Thank you.
3:38 Subtle Technology Connections reference there? Lol
As a retired 40+ years CO Tech (Switchman) I enjoy watching your knowable talks about the CO, it brings fond memories of my working years. Do you have a video that explains why the CO 48 volt battery, positive is grounded? That might be of interest to your viewers.
Good idea. I should do a whole video on CO power!
"And through the magic of having two of them..." Ah, a reference to Technology Connections.
So I’m not the only one that noticed that 😂
As a retired SxS switchman for SouthwesternBell in the 70's, I can't wait for the next video. These bring back alot of memories. Namely a very fulfilling career. Thank you so much.
Worked SxS Switching for Southwestern Bell in Oklahoma City from 1970 to 1977. Where did you work?
@@gpwgpw555 eldon missouri. Class4 and 5 SxS with cama.
THANK YOU, Maestro!
I can claim to fame as 1 individual Data point in Bell's decision to change 0 from Information to Directory Assistance.
kid at 7 whips the dial all the way around, fingertip stuck next to the 0 and lets go.
rng rng ring
"Information"
"Hi, how are you today? How many Teaspoons are in a Tablespoon, please?"
"There are three Teaspoons in a Tablespoon, young person. Have a great day."
also, I deciphered the dialer and tested it.
I could successfully 'dial' any number by tapping the hang-up button, technical term long forgotten.
I learned everything I needed to know about everything, taking a bedside Westclox wind-up alarm clock, with no intention of putting it back together, just like science does.
"The gears is what I was after. Aside from the sharp ends on their shafts pricking my little six year-old fingertips.
Tiny spinning tops.
Thank You!
I don't know how I rabbit holes into your video at 4:30am on a sleepless night, but as someone who was obsessed with the 2600 magazine (even more so the very fact they were sorta hidden at my Barnes & noble) I absolutely love your channel and am so excited that I basically just found a new channel to binge. Thank you for making this content. ❤
“Through the magic of having two of them” haha! I love the Technology Connections reference!
I can’t get enough of your videos, Sarah!
Not only do you know your stuff, but you’re excellent at CONVEYING that info, while keeping it interesting.
Looking forward to the next installment!
The look of absolute joy on your face when these old machines still work and ring a simple bell! Wonderful 😊
The 5 ESS uses the High Level Service Circuit which can generate any ringing voltage plus any coin phone control voltage. It is a four quadrant voltage source completely under software control. Output was +/- 200V. If a power surge came in during ringing, it would convert it to DC and charge the office battery. IIRC, it is the TN848, but it has been a long time.
Great job Sarah. I started my telephone career in 1965 as a Western Electric installer. My first assignment was the M&T building in Nashville, Tn. The ringing and tone generators were kept in the basement.
I started my career with West Electric, February 1963, retired after 36 years service. Today is, 9 11 2022. The worst day in our history I lost three friends in the North Tower. Made all the people that perished on that horrible day rest in peace.
"Ring Off" Love the postcard proudly displayed on your switchboard at 5:42
Excellent presentation, more please.
I was in Vietnam we use magneto field phones and switchboards, no one rang off so the gruff sounding male operator operator would brake in into the phone conversation saying "working" and if you didn't answer working working, quickly he would break down the line.
Great walking commentary with following camera work, smooth. Love these old machines. Spotted a nice old Comptometer in the background.
Saw you folks on CuriousMarc's video, and I guess the Algorithm noticed!
"Through the magic of having two of them"
Subscribed.
Great Video. When you make the next video about the ringing generator, tell them that the ringing cycle was three seconds long. It was divided into three groups. Each group would ring for one second in sequence. This way the generator only had to power one third of the ringing phones at a time.
Props to the crew that does a spectacular job of refurbing these beautiful pieces of telephone history
In the Marines, we had TA-1 phones with the same functional magneto to ring a point to point connection. It was often used to shock the heck out of another Marine, though.
Ex-telephone engineer here... loving this. And much of that takes me back decades (too many to admit). Keep up the good stuff.
I often watch videos on the channel, they are very interesting, this one is now a very good summary one of the early telecommunication technologies. Anyway, I think I can say on behalf of many of us, thank you so much for keeping these machines and for them to be seen in operation by those who didn’t even live when they were in their heyday.
Yes thank you
Cool. A WECO 317 wall phone. As a retired Bellhead, I was glad to find a WECO 317 at a rural garage sale. It had all its internals including the magneto and two tired talking batteries!!
It was fun the day the mechanical ring machine contacts welded themselves together and the entire 20K line CO got uninterrupted continuous ringing.
The foley and sound design around 9:38 is stunningly realistic and I love it.
Sarah, great explanation. BTW United Telephone, Independent Telcos used different frequencies on party lines like 16 2/3 Hz 20, 25 and 30 Hz. Subscriber phones had frequency “tuned” bells to respond appropriately. Bell system didn’t adopt that scheme however. Bell used a distinctive ringing like two longs and a short or tip vs ring to ground on two party lines. Who knew!
Great job keep up the work you're doing your educating me and I had 36 years with the company, West electric and AT&T. I never was involved with the power system I was more into the switching systems, but many things you had mentioned I was totally unaware of. As a retiree for a number of years now I'm still learning about how various systems within the system worked. You doing a great job keep it up for all us retired employees. When I look at the older equipment it brings back very fine memories God bless you stay safe keep doing what you're doing you're educating the world actually.
LOVE that shaft coupling!
This stuff was built to last!
Been running a PBX for 10 years now, trained by an old head from MST&T who cut his teeth working SxS and Crossbar, and helped see us through to the age of SIP. He imparted a wealth of knowledge and a love of telephone systems to me, and finding this channel is just so great getting to see all of this stuff actually working.
"Through the magic of having two of them." Lol love the Technology Connections reference there, and I loved this presentation! So informative and easy to follow. Glad this channel has started showing up in my recs!
This is pretty cool. Seeing how the ringing function works electrically was something i never expected to learn.
Wish there was something stronger than a thumbs up for this one! Well done. Great production value on this one also - looks great Sarah!
Thanks again for this great info. Looking at the larger ringing plant at the end of your video, I recognize the GE motor used for the AC motor in that setup. It looks almost exactly like the Western Electric branded GE motor in my 1925 BF Sturtevant workshop fan.
Thanks Sarah! I thoroughly enjoyed that and look forward to the next installments. Your enthusiasm and passion show through and it is great to see how comfortable you have become in front of the camera.
I worked for Southern Bell Telephone in Ft. Lauderdale, Fl. 1969-1983 I/R Switching Tech and Special Services.
Cleaned the drums on ringing machines many times. Cool Museum
Stumbling upon this video has been a delightful turn in my quest to delve into the workings of rotary dial phones, particularly as I aim to construct supporting circuitry to transform an old rotary dial phone into an engaging conversation piece at my workplace. The clarity and ease with which you elucidate the theory of operation are truly captivating, showcasing your exceptional talent for making complex concepts accessible. It's evident that you've invested considerable thought and effort into creating this content, and for that, I extend my heartfelt gratitude. Your video has earned a like and a new subscriber in me, and I eagerly anticipate exploring the rest of your channel's offerings. Excellent work!
I had been curious about this topic and your video was suggested by the TH-cam algorithm. So glad it was! Very educational, organized presentation and it is obvious your knowledge on the topic is exceptional. Educational and entertaining video. Excellent work.
I never really thought about how complicated the old telephone system was. And how ingenious! It seems pretty wild that this stuff was hand built at one point, too.
Condensed and informative videos on a complex technology that most of us have grown up with and completely take for granted. I remember as a teenager being able to push a combination of buttons or jiggle the receiver hang up switch and voila....access to a party line.
Thanks for the passion in this technology and making the videos.
Can’t wait for that next video about the ring machine. Nice job Sarah!
In my small home town, we moved just "out of town" when I was 6, about 1954, into the house Dad and Gramps had built before WWII. The phone was still a wall mount hand crank "Farm" / country/ party line, with more than 20 customers. Our number was 19F4 which meant we were the 19th customer on the "Farm" line and our ring was "fast 4" or 4 short rings.
Love this series. Such clear and illustrated programs. I built switchboards for Stromberg-Carlson in mid-1950s. You’ve put together a wonderful history of phone technology. Thanks for keeping it alive.
Thank you so much! I'm restoring an antique phone And this was very insightful. Can't wait to hear it ring again
I'm going to be 100% honest here because that's me...I really found you to be odd and slightly offputting when I first saw you in a video. That said, you are one really knowledgeable individual. I find your information to be extremely concise and well layed-out. I like the tone and cadence of your delivery. You made me a fan. It's all your fault! 😆
Very cool, and very helpful! I recently acquired a couple of 1950ish magneto phones, which I intend to wire up as an intercom. A lot of folks who've written up docs on using phones wired locally as intercoms lament that they don't have the devices needed to make the phones ring, and seeing this explanation reassures me that having the magnetos will sidestep that.
Every time I think the production quality of your presentations has peaked, I'm proven wrong. Great work - looking forward to the next installments!
Absolutely wonderful! Can't wait for the next video. Where else will you find videos with people excited at describing ringing generators and tone plants!
Excellent, Sarah! Looking forward to more on the ringing machine.
I have loved telephony since I was about 6 years old. Really excellent presentation (I kept wanting it to go on longer)
Sarah, this is so freaking cool! I've learned so much from this video and it makes me so excited to hopefully be a part of preserving history at this museum someday!
Perhaps an in-depth topic for one of your videos regarding ringing: multiline business phones from the 1960s-80s (1A2 phones) often had single gong bells that only responded to 1/2 of the AC wave. If you put a diode in series with the bell, it would either ring normally, or not at all, depending on which side of the AC wave it blocked. This came up because with these phones, ring voltage was provided on a dedicated wire pair, separate from the tip/ring pairs from the telco, and ringing was "programmed" by the installer, to control which incoming lines rang which extensions on the multiline sets. A diode matrix block was used to control this, one diode per line per extension. The diode matrix managed a locally provided 30Hz ring voltage that was usually a small AC "frequency generator" (often a Western Electric 118a, or sometimes larger KSU supplies) that divided down the 60Hz to 30Hz using a special phase shifting transformer. I remember wondering why the presence of the diode matrix didn't affect the loudness of ringing in these phones, but soon came to realize that the bells in these phones only rang on 1/2 of the AC wave anyway, with or without the diodes. To use diode matrix ringing, the ring capacitor in series with bell in each phone set had to be bypassed, and the installer had to get the polarity of the diodes right, otherwise the bells wouldn't ring at all. The bells actually have a red and black wire, and if you accidentally switch them, the bells won't ring if a diode matrix is used to control extension ringing, as they really did /nothing/ if the wrong side of the AC wave was blocked by the diodes.
"And through the magic of having two of them..." Ahh, I see, you are a person of culture...
i see you are also a person of culture
You're a great educator and communicator. Thanks for the great video. Not only do you describe how the magneto works, you give great examples of how it was used. I really appreciate your videos! Thanks, and be well!
Every one of these videos is better the last! I miss you guys and the museum a great deal - I’m glad to see that scope getting some good use :D
Zip!
Absolutely wonderful, as always, thanks again for positing!! I’ll be merrily awaiting your next video. :)
Thanks Sarah, excellent presentation. Looking forward to the next one
I mainly do digital phone systems, but I absolutely love learning about the really old telephone gear. Thank you for the video!
In some ways, a central battery, POTS phone line is more reliable than digital IP phone service. If your power goes out, the phone still works, unlike your IP phone, which goes dead when your network goes down.
Yep, I run a PBX, so mostly H.323 and SIP IP endpoints/signalling. But we have a fair share of analog going on for lots of longer runs and fax/data. Nice to get a taste of the old school with the analog stuff.
i love your videos. so facinating. I love the phone system and i'm always glad to learn .
I have to agree, that spring system on the ringing machine is neat! A nice dampening system.
Hi Sarah This brings back a lot of memories of my days at Cincinnati Bell back in the 50's and 60's when we all studied the old principles. A lot of what you are describing goes back further but I still have the old books that I was given back then. I watch all your videos and find them very well put together. I hope to get out there late this year and visit the museum. Steve
These are the best! Great info in an ideal length video. Looking forward to visiting the museum this year.
Great accessible summary - loved the demos. Your presenting knowledge and enthusiasm for the subject kept it very engaging.
Nice to see you back! Great episode and lovely antique tech, because what else would I expect from you? Goofing off for a while? Yeah, that's cute too.
Missing Astrid a bit :)
By the way, I got an idea of connecting (probably by VoIP) the Connections Museum with Sam Battle's one (Look Mum No Computer / This Museum Is Not Obsolete). Would be cool to call each other, and even cooler to set up a trunk connection :)
You have an excellent presentation style. Not too dry and not too "over the top." Very cool to see younger generations knowing how the "electromechanical world" used to work :) Oh and LOVE the mention of phone phreaks :) Evan Doorbell would be proud!
Technology Connections shout out at 3:38
Great job with the channel and this cool video, I also want to point out the fact tha the production quality and how much fun following the video was.
I love watching your videos. I would love to check out the museum one of these days.
Glorious!!! You had a LOT of fun making this...
I LOVE the still frame used for the thumbnail 😄
Thanks! That was wonderful. I want to go see the museum! Great fun presentations.
The quality of this video is amazing! Thank you so much for all your passion about phone tech, it really shows through!
The ringtone as I remembered was 109 volts, the ring generator was down with the power supply for the communication systems. All the wet cell batteries will link together either 24 or 48 volts. I am not a power expert but I am an expert in electronics switching number one number four number five, tsps and ETS systems, 36 years, working for Western Electric, AT&T, qualified system specialist. In all of the above. Today's date 9/11/2022, the worst day in our history. Make all those that lost their lives rest in peace.
I only got the 10c spiel on ring generators, I've mostly done wireless cell/MTSO. It probably varies depending on generation of equipment, manufacturer etc. The ring voltage was a doubling of whatever the DC plant voltage was. A 48v plant is almost never running at 48 volts. Primarily, at least in smaller plants the manufacturer's specified float voltage range for the batteries dictates how the voltage is set. Plus you figure in voltage drop between the DC plant and the ring generators but that should be small. So you can see 49 and change to 56 volts at the plant. Typically 52 (ish) volts. I know I've come across 110v ring voltage, it hurt.
Just came across your channel. Very good info.
FWIW, you are aware that the spring between the motor and the magneto at 9:33 is to align the two different shafts so there is no misalignment and take up shock between the 2.
I just discovered and subscribe to your channel and I'm totally addicted on the first video! I am an IT engineer retired and have always been fascinated by anything with mechanisms that are associated with everyday things like the telephone so keep up the great work, your videos will be viewed by thousands of thousands of people for instruction in the future.
I loved the #6 dry cells. My grandparents had two of them powering their doorbell. Railroads also used them heavily in the old days.
They're often called ignition batteries. Early cars ran their ignition systems off of them. Four wired in series make 6 Volts, just right to excite the ignition coils of a car. Ford changed things when he decided to run his model T from a magneto instead, to avoid reliance on batteries that could go dead at inconvenient times. The batteries could be saved for just starting, instead. Also, when I went to school, we used them frequently in our science labs.
I love your videos my dad worked for northwestern bell for 40 years
I was always told it was 80 vac half wave, in other words 80 volts DC turned on and off at 60 hertz. I used to install phone systems for a telephone company in the 1980's. All the literature I ever read at that time said 80 vac half wave for the ring voltage and 48 vdc, We had one customer too far from the switching stations, who had multiple phones in there HUGE "mini" mansion style home. The phone line could NOT ring all the phones nor could it enough current for voice if multiple phones were picked up. Using a few transformers rectifiers and relays we created a mini switching station, when a phone was lifted within the house, the 48vdc generated by a transformer, bridge rectifier, a few capacitors, one 150 ohm resistor and a relay with a 150ohm coil, would connect the house hold phones to a transformer for voice, and connect the telephone line to the secondary of the phone line. Ring current for from the telephone line, would activate a relay instead of a bell, and the relay would in turn supply 80 vac half wave to the house hold system which in turn rang the the telephones through out the house. Since the voice signal was passed through a 1:1 transformer, the signal was lower than usual, but was still completely audible.
This is one of the most comprehensive & easy to understand explainer about telephones I ever seen. I really love your presenting style, like a modern version of Tim Hunkin (look him up if you haven't heard of him).
Congrats on making it into the Overflow blog
This is the coolest personality i've ever come across on a tech channel... you had me at the coupler sound-effects but I Dream of Jeannie clinched it. Subscribed. :)
"Through the magic of having two of them"? Ha, you copied that from Alec at Technology Connections, huh?
This is absolutely fascinating! Keep these videos coming!
Thanks for a great video. You're a natural instructor. Of course modern technology performs light years ahead of this old school stuff. Though the minds that built this cutting edge technology of a century ago, deserve respect. As well, the craftmanship of yesterday often surpasses modern build quality.
Thanks for the very informative video. I'd heard the phrase "Ring off" before but never understood its origin. I find the evolution of technology quite fascinating and the creative ways that problems were overcome.
This is so super interesting, big thank for preserving this impressive know how of our past generations!
The ring voltage was a small workplace "hazard" for those that worked on telco equipment. It was a spicy reminder if you touched connections while ring voltage was present.
Great job Sarah, Your knowledge of the phone system is phenomenal! You have a very understandable presentation of the subject. Keep up the great videos.
Ok omfg.... I've "known how it all works" since a curious kid 30 years ago but holy shit you just made it all click with regards to how our phone being "off the hook" closed the circuit allowing it to reach the CO... OMG FINALLY after decades it actually clicks in my brain. THANK YOU
Amazing, I've always wondered if there is more to the phrase "Ring Off", even dictionaries skip the history and say it's just something people say at the end of a call. Thank you for solving this mystery.
I wondered about the etymology of the phrase "[to] ring off". Now I know. Thanks!
I love this so much! I'm a VoIP engineer and telecom nerd! I have GOT to come check this place out!
That’s great presentation, the large effort I assume you put into it for sure paid off! Thanks for sharing this very educational video!
Thank you for all your hard work!
Yet another fantastic video! Thank you!
This was awesome! More like this, PLEASE AND THANK YOU! 😁
That is so cool! Would love to visit your museum, but unfortunately it is a bit too far away.
I'm a recent subscriber, but I can see I am going to have to start binge watching - you are a very good teacher!
Really interesting video, looking forward to the rest.
"…and through the magic of having two of them…"
I sense a Techology Connection
"It rings a bell"...
... and that wasn't the only alec-ism in this video!
Great vid! Love any and all telco history.
2:25 nice to see, i still use this extra ringing bel in my house from i think 1963 and it works well on the telephone line in 2024.