Multi-Line Telephone Intercom

แชร์
ฝัง
  • เผยแพร่เมื่อ 12 ธ.ค. 2024

ความคิดเห็น • 141

  • @DryLog420
    @DryLog420 5 ปีที่แล้ว +6

    I made something simmilar for one of my first microcontroller projects. Your design is very nice, and I'm thinking if someone added a microcontroller to it, the "ring" line could also become a second line for 2 private conversations. With a few small changes I must add. Great project man very detailed!

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      Obviously if you want a second talk circuit, you'd need numerous more relays. It becomes an entirely different project. This project is basically "selective ringing."

  • @simonforget280
    @simonforget280 5 ปีที่แล้ว +3

    A known pair of 26AWG wire, one 9 to 12VDC battery and two test sets are more than enough to have two lineman/splicers to work together on phone lines. Thinking about this makes me missing that time... except when it was cold, hot, rainy, snowy, icy rain, windy in humid man holes or on spikes at the top of a pole for twelve hours. Keep up your excellent work!

  • @Derfboy
    @Derfboy 5 ปีที่แล้ว +35

    Holy crap, I haven't set up a system like this in.....decades...thanks for sharing! Loved it!

  • @4-6-3DP
    @4-6-3DP 5 ปีที่แล้ว +3

    Nice! I’ve scoured the internet looking for a commercial solution for something like this, and couldn’t find one. I’ve got a bunch of ancient phones, and will give this project a try!

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      Good luck with your project! If your phones are *really* ancient, with electro-mechanical ringers, this power supply may not provide adequate ringing voltage.

  • @gregm.857
    @gregm.857 3 ปีที่แล้ว +7

    Very cool and simple project. Thanks for the video.
    I built my own relay-based PABX when I was in college ~1965. It was all rotary pulse dialing, no DTMF. In addition to phones around the house (my brother's room, dining room, darkroom, etc.), we strung phone lines through the trees to some neighbors houses so we could talk to our friends. Rather than a common "party line" only the called party could talk to the calling party. Also used a real 20Hz 90v ring generator, since the phones all had electro-mechanical ringers.
    Thinking about your project, my personal feeling is that if anything needs improvement it's the ringing generator. Indeed, the high voltage requirement presents some design challenges. If I can come up with any relatively simple solution I'll send it along in case you ever want to make a "Mark II" version.
    Oh yeah ... wasn't it a PITA to punch the holes in the steel chassis? Solve that problem and the rest of the project is cake!

    • @BurkenProductions
      @BurkenProductions 2 ปีที่แล้ว

      Nice! How did you manage the part where only 2 ppl could speak to each other? Can't wrap my head around it.

    • @gregm.857
      @gregm.857 2 ปีที่แล้ว +4

      @@BurkenProductions Thanks. I'm not sure I understand exactly what you're asking, but let me summarize how my system worked.
      Each phone had its own series "line relay." Initially all the line relays received voltage from the supply. When one phone went off-hook, that removed voltage from all the other line relays; so other phones could not initiate any actions. Thus only one conversation was possible at any given time. (Given that we had only 7 or 8 extensions, and only 4 people were normally involved, it was unlikely that we'd have a need for simultaneous conversations.)
      The "active" phone also controlled "B" and "C" relays, which in turn controlled the stepper switch. When the phone dialed some other number, the stepper selected the "called" phone. If the called phone was (presumably) on-hook, ringing voltage was sent (via stepper switch contacts). If/ when the called phone went off-hook, ringing voltage was disconnected and called phone was connected to calling phone. That allowed the conversation.
      I honestly don't remember whether the two phones had a DC connection path, or whether there was a series "talk" capacitor connecting the called phone back to the calling phone. In the former case, the system would remain "tied up" until both parties hung up; in the latter case the system would be controlled by the calling party.
      In retrospect some other features would have been nice ... maybe some sort of audio tone injected into the talk circuit if a *third* phone went off-hook and wanted to use the system. Then when the first two parties heard that tone, they could hang up, freeing the system for the third phone. Etc. But this was 1965, when there no such thing as consumer-level logic chips, and I was spending my allowance to buy surplus relays.
      If that didn't answer all your questions, let me know and I'll try to recall more details.
      Cheers!

  • @HIEPPIEFUSARO
    @HIEPPIEFUSARO 5 ปีที่แล้ว +15

    Hey you are the guy from The Current Source. Nice to see you here

    • @AmRadPodcast
      @AmRadPodcast 5 ปีที่แล้ว +6

      I am! Thanks, it's nice to be here.

  • @whitesapphire5865
    @whitesapphire5865 4 ปีที่แล้ว

    I'm liking very much! And to think, I spent a wad of money to buy a pabx to do this job. We connected my cabin and my dad's bungalow, and then added a few other phones around the farm, not so much that we needed them, but because we had all those spare outputs going, well, spare!
    That pabx is a pretty well feature rich system, and it does its job admirably, but it's not as much fun as this setup!
    Years ago, we had a very basic "upstairs/downstairs" (two telephones) and basic power supply so that we could call from ground to first, and vice versa, floors of the house, but it lacked the sophistication of this system. It could only ever be two phones, commoned on a single DC line, with a separate ringer circuit.
    A Nice video/tutorial, thank you.

  • @sharedinventions
    @sharedinventions 5 ปีที่แล้ว +14

    Very professional, quality content. Thank you! I have collected some old phones in the hope, that I will use them in a project like this some time. At least now I know how to do it properly.

  • @TonyBarr99
    @TonyBarr99 5 ปีที่แล้ว +3

    Finally, new content from one of my favorite youtubers, The Current Source! I'm so glad you are doing well!

  •  5 ปีที่แล้ว +3

    Very simple approach. Congrats. I am surprised that you did not have to add a series choke inductor on one of the line wires. The 33 ohm resistor + LM317 have a rather low impedance compared to the audio signal. When I tried this back in the 80's, I had added the primary winding of a power transformer in series with the +9V DC supply, otherwise we would not hear anything. Thanks.

    • @K2teknik.
      @K2teknik. 5 ปีที่แล้ว

      Yes, you need a coil in serial with the power, otherwise you will just kill the audio with the power supply, but here they use a resistor, will work but not that well as a coil.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      Agreed 100%. Think about a TELCO central office subscriber line circuit. A big mother 48v battery (0 ohms AC impedance) in series with two relay coils which produce a *high* impedance to the audio.

  • @vsevkrawczeniuk8019
    @vsevkrawczeniuk8019 5 ปีที่แล้ว +2

    Derek is my favorite host on this channel so far! Great work!

  • @chrissnyder2091
    @chrissnyder2091 4 ปีที่แล้ว +2

    I have build similar ring generators using a astable 555 timer driving a push-pull amp with 2 power transistors and a large value cap in series with the out put, works great.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      IMHO that's a much better solution than the one presented here. Better waveform, fewer HF harmonics so less problems with transformer impedance, etc. The challenge is finding a transformer that can pass 20 Hz with reasonable efficiency.

  • @armouredco6935
    @armouredco6935 4 ปีที่แล้ว +1

    Thanks for the video. It turns out it's kinda easier than I thought. I'm building a half scale M4A2 Sherman tank for a School project. And I was looking around to see how to make an intercom system and now I know how 👍🏼

  • @williefleete
    @williefleete 5 ปีที่แล้ว +5

    I have sort of enjoyed telephone systems, especially electromechanical exchanges. I think what you made is a very crude PABX

  • @danstark462
    @danstark462 4 หลายเดือนก่อน

    Hello sir. You have made a informative vid on telephone intercom. Very clear and professional Thank you.
    My project idea is to make my landline phone to announce the arrival of guests coming down my driveway with a distinct series of audio rings.

  • @dalemettee1147
    @dalemettee1147 2 ปีที่แล้ว +1

    In my retired years, I now help out with the senior center's drama club. I am the sound guy. I use the PA system for all sound reinforcement and sound effects. One of my projects is to use old phones for certain skits. Ringing the phones would be great. So far, after reading up on the requirements for ringing the older phones needed a current of ~ 90 v. @ 20 HZ. So according to your video, that spec. can be obtained without too much bother. So, can I actually build a circuit for this. A little help would be much appreciated. Thanks Dale Mettee

  • @colonelbarker
    @colonelbarker 5 ปีที่แล้ว +3

    This video was so good. Thank you for the content. It's nice to have a project I could make and understand that wasn't hooking a Pi upto something..

  • @scholi3039
    @scholi3039 2 ปีที่แล้ว +2

    Exactly what I was looking for. Very well explained. Thank you so much ❤️

  • @awesome3165
    @awesome3165 5 ปีที่แล้ว +2

    Big thumbs up to this guy. He's really good.

  • @danideca69
    @danideca69 ปีที่แล้ว +1

    i have been looking, for a long time, this informarion. thank you very much

  • @Subgunman
    @Subgunman 11 หลายเดือนก่อน

    There is a company that makes a module that will provide 90 volts at 20 Hz. Unfortunately I do not have the link saved on this computer and the other machine is in deep hibernation.
    A multi number add on would be nice for this system, don’t have to worry about dialing binary. A simple 3 or 4 digit extension would suffice. No need to have fancy ring cadences either. The only thing a ring cadence would provide is a signal to a decoder within each phone on the system so it knows when it is called. Would eliminate "home run" extensions when a loop would suffice.

  • @duuqnd
    @duuqnd 5 ปีที่แล้ว +5

    I've always wanted to learn more about analog phones. Great video, too bad about the low amount views though.

  • @zhblue
    @zhblue 5 ปีที่แล้ว +1

    best explaination on how telephone works ,ever !

    • @gorillaau
      @gorillaau 2 ปีที่แล้ว

      This is not a bad explanation that gets you most of the way for an PBX. Add an arduino such that if a party line is in use, then other calls can't be made. There are some chips that is made for the matrix switching, such as 8 rows by 8cols or even 16 lines. This video and schematic has got me thinking!

  • @sandro-here
    @sandro-here 5 ปีที่แล้ว

    Explaining tech, you're doing it right. I was thrilled.

  • @NiHaoMike64
    @NiHaoMike64 5 ปีที่แล้ว +5

    Have you thought about making a circuit that uses a USB sound card and GPIOs to interface an analog phone to VoIP using a Raspberry Pi?

    • @tieline1333
      @tieline1333 5 ปีที่แล้ว +1

      Just use a HT502 ATA?

    • @NiHaoMike64
      @NiHaoMike64 5 ปีที่แล้ว

      @@tieline1333 An open hardware solution would be nicer. Also, for a lot of individuals, they'll still need the Raspberry Pi or whatever to run Asterisk on.

  • @williefleete
    @williefleete 5 ปีที่แล้ว +1

    I might make some improvements to this and design a proper PCB, I might use discrete logic (or maybe an arduino) to decode the DTMF decode output to individual signals for the phones so at least 9 or so phones can be used and maybe use 0 to switch into to the landline etc if used. I would have to treat the phoneline as another phone and design the input of the landline jack to act as if it was a regular phone, so it will likely need to be isolated and need to detect ring signals broadcast to all phones and take the line off hook when any of the other phones go off hook

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว +1

      You don't need an Arduino. Just use a BCD-to-decimal decoder, e.g. 7445, to drive the relays. Interface to landline using a relay and 600:600 ohm audio transformer, and you'll need some logic to keep that landline circuit latched on until the calling local phone goes on hook.

  • @optroncordian7863
    @optroncordian7863 6 หลายเดือนก่อน

    You could use a binary to decimal decoder chip to extend the number of lines.

  • @williefleete
    @williefleete 5 ปีที่แล้ว

    I've improved on the design a bit, adding the ability to address 8 individual phones and the ability to access a landline etc, I've added a microcontroller to the DTMF decoder and a 74HC138 to the ring relays. I have to revise the board a bit but if you want the design files etc let me know

    • @sam462m
      @sam462m 4 ปีที่แล้ว

      Can you send that to me as I am very interested in this

    • @rossherbert1591
      @rossherbert1591 4 ปีที่แล้ว

      I am also interested in this project

    • @williefleete
      @williefleete 4 ปีที่แล้ว

      @@sam462m github.com/WRFleete/PABX-project has the code + schematics + gerbers, havnt tested with the RJ45 connectors on that schematic etc but I did have individual ports for each phone. Code may be a bit of a mess and I may comment on it a bit. The code has basic support for pulse dialing as well and the ability to connect to a POTS/PSTN phone line (and dialing to get the "outside line" and "hold" feature)

    • @williefleete
      @williefleete 4 ปีที่แล้ว

      @@rossherbert1591 posted a link in another reply to the git repo

  • @mikkenieminen9603
    @mikkenieminen9603 5 ปีที่แล้ว

    I miss those old golden times.

  • @drsambhajirathod9700
    @drsambhajirathod9700 2 ปีที่แล้ว

    Hey, It's pretty cool one ! Can you please make a project of circuit acting as bridge to connect GSM SIM module (eg SIM800L) with normal phone instrument (Benatone Concept 711) to dial phone and receive calls coming to sim number ?

  • @chadith
    @chadith หลายเดือนก่อน

    I want to incorporate this into our home that we're in the process of acquiring using the existing phone lines to all the rooms. I'll just need to find the main junction of the individual lines.

  • @repeatman
    @repeatman 4 ปีที่แล้ว

    You gave me an idea of repurposing a box of old telephones. I just ended up just buying a pabx unit due to my lazyness but thanks for the idea! :D subscribed!

  • @kbejustervesenet7261
    @kbejustervesenet7261 หลายเดือนก่อน

    Did you ever expand the system to be able to dial out to the GSM net ? (and in from it??)

  • @Sohave
    @Sohave 5 ปีที่แล้ว

    Another interesting version would be one that works with rotary phones, Instead of a touch tone frequency rotary phones sends out a pulse. An Arduino set up to read the pulse could work as the decoder.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      I've thought about the same thing. In fact the Arduino could also accept input from the DTMF decoder IC, so it would work with either type of phone dialing.

  • @RotMos12
    @RotMos12 5 ปีที่แล้ว +3

    Awesome video! Very well explained and interesting content. Looking forward to more videos.

  • @Mezmorize99
    @Mezmorize99 5 ปีที่แล้ว +2

    Nice to see you on this channel :D

  • @techguy9023
    @techguy9023 3 ปีที่แล้ว

    Dip package is easier for the DTMF decoder if you can still find one

  • @QlueDuPlessis
    @QlueDuPlessis 5 ปีที่แล้ว +1

    Nice, but how do we make it capable of loop-disconnect dialling? Oh, and can we do it entirely with relays..,
    :p

  • @anthony4acre
    @anthony4acre 4 ปีที่แล้ว

    Nice simple system for a large house.

  • @JEB2024
    @JEB2024 2 ปีที่แล้ว

    😆 loving the video editing
    Thanks man for sharing your art

  • @bowlerhatman01
    @bowlerhatman01 ปีที่แล้ว

    Thanks for the explanation! I may have just missed it, but can you please explain how the system recognises when the phone receiving the call has picked up? I dont understand it, as I can't see any way for the circuit to determine if phones are on or off the hook.

    • @jackevans2386
      @jackevans2386 8 หลายเดือนก่อน

      The system doesn't recognize when the phone receiving the call has picked up, but only rings for as long as the caller is pressing his keypad button, so a quick press should be enough for the called phone to realize someone is calling them, as long as someone is in the room that is.

  • @spokehedz
    @spokehedz 5 ปีที่แล้ว +1

    This is so wholesome.

  • @chrissimpson4436
    @chrissimpson4436 4 ปีที่แล้ว

    Great presentation. I built it using a modified chinese 9170 module, works great except for the current source supply for the phones. Seems to work great at around 9v out of the 317, but as i crank it up to 24 the DTMF signal diminishes, stops working around 13v. I use cheap oricom tp4 phones, does the current source for this (317) need audio decoupling with a choke or filter??? I guess there is a lot of "phone guys" out there, suggestions welcome, THX Chris

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว +1

      Let's start with the design parameters for a POTS telephone system. About 48v DC (very well filtered, but regulation not too critical) when all the phones are on hook. Then you need enough series resistance so the voltage *at the phone* drops to around 10-15 volts when the phone is off hook (even a bit lower voltage is OK). This will make the tone generator and talk network work correctly.
      The series resistance is important because it isolates the telephone audio from the zero ohm AC impedance of the power supply. In a real telephone exchange, this resistance comes from the windings of the coils on the subscriber's line relay. The coils have inductance, which provides even more isolation than a pure resistance would.
      Many local office systems (PBX = Private Branch Exchange) will start with 24v DC, rather than 48v. No problem, you just need less resistance in the relay coils, to achieve proper working voltage at the off-hook telephone.
      My point is that you do not need a constant current supply. You can achieve good operation with a random DC supply (must be well filtered!) and series resistance, or better yet series inductance. You do want to end up with around 10-15 volts at the phone *when* the phone is off hook.
      The constant current supply is OK. When one user is talking and that one phone is instantaneously drawing less current (negative audio peak), the current will be forced into the other phone, and vice versa ... that's how the audio signal is transferred between phones. Personally, I prefer filtered DC *voltage* supply with series resistance or inductance ... that's just me, what's what the phones were designed for.

  • @louiesrego
    @louiesrego ปีที่แล้ว

    are there online stores sell this kind of project?

  • @lit2021
    @lit2021 5 ปีที่แล้ว +2

    What if you ring a phone that's already off hook? Would the speaker in the phone burn out?

    • @AmRadPodcast
      @AmRadPodcast 5 ปีที่แล้ว +3

      Ah, good question that I didn't cover.. phones are equipped to handle a horrific barrage of voltages and transients that could appear on the line, including ring voltage when off hook. It just makes a clicking noise on the receiving end. If I had used an off-hook detection circuit and maybe a microcontroller, then I could prevent this from happening. But, I wanted to keep it relatively simple so that anyone could build it. Thanks for the excellent question.

    • @Claudiu.
      @Claudiu. 5 ปีที่แล้ว +1

      @@AmRadPodcast Still a very good coverage and nice way of explaining them. Hope to see more of your videos here!

  • @BurkenProductions
    @BurkenProductions 3 ปีที่แล้ว

    it's about 110 volts in a regular phone system for ringing.

  • @marbyyy7810
    @marbyyy7810 5 ปีที่แล้ว

    Cool video! I’ve actually been thinking about old phones lately and what to do with them

  • @nsenthilkumar2007
    @nsenthilkumar2007 ปีที่แล้ว

    I want to know, Matrix Visionpro308 maximum distance from epabx to normal beetal c11 phone distance ?

  • @abittwisted
    @abittwisted 5 ปีที่แล้ว

    Could you utilize the power from the phone line itself and could you make an intercom even though the land line is still used as an outside line? Very interesting. Interesting thing is our home was setup initially to have 4 different land lines and all the lines still have power.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      It's not clear to me exactly what you want to do. However, the TELCO phone line provides a maximum of about 50-75 mA, not nearly enough power to run the ring generator and other electronics in this system.

  • @chrisrichard298
    @chrisrichard298 5 ปีที่แล้ว

    75 mA output is a little hot. Standard lines are spec'd at 32-37. Too hot and you can burn up components in the phones. Probably won't hurt the old electromechanical phone, but those electronic phones and cordless phones won't like 75mA for too awful long.

  • @liyak1371
    @liyak1371 ปีที่แล้ว

    Hi there, can I buy this kit from you?

  • @chadith
    @chadith หลายเดือนก่อน

    Would this work with old rotary phones?

  • @WriteSign
    @WriteSign 10 หลายเดือนก่อน

    Oh.... I really want to buy this system. I would like to be able to build it myself but wow, this is awesome stuff and I fear I am not this level yet. I was saying to another phone modifier youtuber "I've been steadily going deaf for a while now & I got these awesome rotary phones with a red blinking light on top (I'll need two more still) that I want to hook up in all the rooms of my house so I can blink the kids and tell them I want them to come help me with something (yes people, deaf doesn't mean I can't speak anymore LOL). There are some deaf aid things like it, but it is basic tech and should NOT cost an arm, a leg, a pint of blood, and your first born for crying out loud! Honestly, the best I've found is ordered out of England and the shipping costs more than the product! Also they are ugly as sin, without even a fraction of the (finished & beautiful) look you've created. They are more like cheap, plastic junk that never caught up with modern tech (which are trying hard to prove that Deaf lives Don't matter). Maybe it could have a cool toggle switch wall panel to ring each phone! I would colour code them and all 💗💖" I really love that it is blue too... Silly, but I love it!

  • @fjeinca
    @fjeinca 3 ปีที่แล้ว

    16:40 lol, this is a great little vid, thanks 🙏🏻

  • @RM.-_-.
    @RM.-_-. 3 ปีที่แล้ว

    Taking cup phones to a whole new level!

  • @henrydocksis7408
    @henrydocksis7408 3 ปีที่แล้ว +1

    This project is a beautiful but an error is hidden in the circuit of this multiline telephone. Here is the error: phone 4 calls phone 2 and at the same time phone 4 is communicating with phone 2, calls phone 1, phone 3.
    For telephones 1 and 3 the line is occupied by telephones 4 and 2. and they cannot communicate at the moment
    With this circuit only 2 telephones can be called and the other telephones are blocked until the end of the calls of telephone 4 and telephone 2
    In order for it to have two instantaneous communications at the same time, the circuit should be modified.

  • @charliebowen4232
    @charliebowen4232 5 ปีที่แล้ว

    Very cool project... I am going to have to try this!
    By the way... where did you get you facehugger shirt?

  • @user-xz7fk3iz8w
    @user-xz7fk3iz8w 4 ปีที่แล้ว

    Hi , I tried this project . But I find that the relay keeps chatterring and the bell keeps ringing in the phone. could you help me to rectify this ?

  • @anasaffection300
    @anasaffection300 5 ปีที่แล้ว +1

    U r wonderfull... Thats content I was googling long time... thanks to share this.... well done

  • @user-xz7fk3iz8w
    @user-xz7fk3iz8w 4 ปีที่แล้ว

    Is there any provision for privacy , like an engaged tone when a third user tries to make a call ?

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      Obviously no such provision, since all the phones are normally connected together on the "party line."

  • @HermanTheHacker
    @HermanTheHacker 5 ปีที่แล้ว

    09:47, Column=vertical and rows=horizontal. You said the opposite.

    • @AmRadPodcast
      @AmRadPodcast 5 ปีที่แล้ว

      Not so sure about that. The ‘text headers ’ may be one direction, but I’m speaking about the buttons. Columns of buttons going vertically, rows of buttons horizontally.

  • @mrfincher
    @mrfincher 5 ปีที่แล้ว +2

    interesting topic and great explanations!

  • @exosdel
    @exosdel 5 ปีที่แล้ว +2

    Great project!

  • @brandtharen
    @brandtharen 5 ปีที่แล้ว +8

    Now it needs to be extended to support pulse dialing 😁 . .. .... ........

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      Just add a stepping relay, plus "A," "B" and "C" relays to control it.

  • @SimontheSayer
    @SimontheSayer 3 ปีที่แล้ว

    This is very cool! One question: Any chance this will work with rotary phones? (I have a large house and very old phones on hand).

    • @0ciii
      @0ciii 2 ปีที่แล้ว

      It wont.

    • @jackevans2386
      @jackevans2386 8 หลายเดือนก่อน

      Yes it WILL work but you'd need a pulse to tone converter as well.

  • @looselycollected7505
    @looselycollected7505 5 ปีที่แล้ว

    I'd love to have a set up like this. But I'm not really that good with electronics. Especially soldering. We've been buying cool old novelty phones. We just bought a house and I thought it would be cool to set them up as a home intercom. But after watching this I'm not sure that I could pull it off. It all seems way over my head.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว +1

      Talk to the electronics shop teacher at your local high school. He will set you up with one of his students who would love to build this and would appreciate a little cash in return.

    • @looselycollected7505
      @looselycollected7505 3 ปีที่แล้ว

      @@gregm.857 I don't think we have hardly any shop program at our local HS anymore. A lot of it was shut down in the 90's after I graduated and went to college.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      @@looselycollected7505 Where I live, most of the shop programs have been moved out of the local high schools and into centralized vo-tech schools. Maybe your local HS administrative office can direct you to a nearby vo-tech school.
      Alternatively, try the local amateur radio community. Admittedly, times have changed, and now a lot of "hams" do NOT know how to solder and build their own gear; they just buy a radio online and start talking. But there will be a few "old timers" who are proficient at hardware construction and might be eager to help you with this project.

  • @sarhtaq
    @sarhtaq 5 ปีที่แล้ว

    Now to grab a few cheap wireless sets and build a wireless intercom :)

  • @internetuser3203
    @internetuser3203 ปีที่แล้ว +3

    Christ this is complicated. Do they not sell a plug and play system?

  • @MrCloroxious
    @MrCloroxious 3 ปีที่แล้ว

    can u sell it for 4 port use .. we just can buy n just link the wire only

  • @mddastgirkhan8338
    @mddastgirkhan8338 4 ปีที่แล้ว

    Awesome idea and knowledge 👌

  • @WWPermaculture
    @WWPermaculture 3 ปีที่แล้ว +1

    is there an off the shelf product that can do this? I would be very interested. Perhaps decommissioned business phone systems?

  • @BurkenProductions
    @BurkenProductions 2 ปีที่แล้ว

    Now make it so you can dial two phones and have two separate conversations as well. A common partyline isn't that good to have.

  • @powerhour4602
    @powerhour4602 2 ปีที่แล้ว

    Can you turn digital DTMF back to analog?

    • @jackevans2386
      @jackevans2386 8 หลายเดือนก่อน

      DTMF is actually analogue audio.

  • @calebbennetts7203
    @calebbennetts7203 5 ปีที่แล้ว +1

    Can we have a ten-minute video with a random sequence of whiteboard squeaks like the ones starting at 1:33?

    • @AmRadPodcast
      @AmRadPodcast 5 ปีที่แล้ว

      Caleb Bennetts yes!!!

    • @REXXSEVEN
      @REXXSEVEN 3 ปีที่แล้ว

      What is that ASMR ?

  • @itanongmokayengineer
    @itanongmokayengineer 4 ปีที่แล้ว

    so informative and clearly explain i thank God for I found this thanks a lot element 14

  • @DancingRain
    @DancingRain 5 ปีที่แล้ว

    I would recommend some diodes on your transformer to protect your MOSFETs.

  • @dnb5661
    @dnb5661 4 ปีที่แล้ว

    What about a dial tone?

  • @yunchen5653
    @yunchen5653 5 ปีที่แล้ว

    The mechanical ringing voltage needs to be very high,maybe the mechanical bell needs 20hz. 50 or 60hz makes it dull

    • @tasbalaa9489
      @tasbalaa9489 5 ปีที่แล้ว

      That's why he connected a multivibrator to a transformer.

  • @Fifury161
    @Fifury161 5 ปีที่แล้ว

    Great project, just 30 years too late! I can drop in via Alexa, ping them on WhatsApp, Life 360, ring their mobile or send them a message via Xbox live! Back in the day my parents had intercoms, which ended up getting replaced by POTS as we had a wired phone in each room. I installed Cat5e cabling in my own home, along with AppleTalk, Cat3, RG59 & generic 6 core cable, only the Cat5e cabling is still used now though...

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      You miss the entire point. The point is to find a "fun" use for some vintage wired telephone sets.

    • @Fifury161
      @Fifury161 3 ปีที่แล้ว

      @@gregm.857 You have your own agenda as you clearly didn't read what I posted...

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      @@Fifury161 I did read what you posted. You said this project was "too late" because now you can use a lot of modern apps (instead of telephones). My reply was that this project is not meant to be the "latest and greatest" but rather it is to intentionally use some thing that is vintage. I don't know what agenda that indicates.

  • @PhilippBlum
    @PhilippBlum 5 ปีที่แล้ว

    Wow, that is really complicated. So, I can be really happy to be born in the 90s :D I mostly experienced VoIP. Compared to the analog way, more simple to implement a multi telephone system :D

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      There is nothing the least bit complicated about this project. It's the heart of simplicity. In fact you don't even need the constant current supply (TELCO systems don't have one in the speech circuit) ... it could be replaced by a filtered supply and a series resistor.

  • @NaoPb
    @NaoPb ปีที่แล้ว +1

    Awesome!

  • @anselmdsouza3077
    @anselmdsouza3077 4 ปีที่แล้ว

    how do i do this with arduino

  • @TylerJorden6
    @TylerJorden6 4 ปีที่แล้ว

    Can you send me one with eight telephones

  • @samengle8068
    @samengle8068 2 ปีที่แล้ว

    sweet thank you

  • @anbu7406
    @anbu7406 5 ปีที่แล้ว

    Pls share sch.

  • @salimkumar9748
    @salimkumar9748 5 ปีที่แล้ว

    Thanks

  • @patriciomonti773
    @patriciomonti773 2 ปีที่แล้ว

    Great. Tks

  • @lalyquispe6327
    @lalyquispe6327 5 ปีที่แล้ว

    Awesome .

  • @rasakkamorudeen86
    @rasakkamorudeen86 5 ปีที่แล้ว

    Good

  • @IchchaSharmaEdit
    @IchchaSharmaEdit 4 ปีที่แล้ว

    DEAR SIR I WANT TO MAKE A FIRE ALARM PANEL CONVENTIONAL(4 ZONE ) HOW COULD I IT

  • @andyblackpool
    @andyblackpool 2 ปีที่แล้ว

    Very interesting I suppose but the question that begs is why bother? Everyone has a mobile phone these days anyway.

  • @pavlekocbek
    @pavlekocbek 7 หลายเดือนก่อน

    year, steere it, drive it, ...that's right. You're insane !!!! :)))) wtf

  • @s1harmonie
    @s1harmonie 5 ปีที่แล้ว

    Just install Asterisk

    • @AmRadPodcast
      @AmRadPodcast 5 ปีที่แล้ว +1

      True this is definitely an option, and maybe a subject for a future video, but in this case I wanted to focus on old analog phones. I do have asterisk running on RPi which I use for daily communication - and to be honest, it's a bit sluggish.

    • @s1harmonie
      @s1harmonie 5 ปีที่แล้ว

      @@AmRadPodcast you can add old analog phones to asterisk by adding a gateway.

    • @dylancruz1131
      @dylancruz1131 5 ปีที่แล้ว

      @@AmRadPodcast npstn.us -- Uses Asterisk Systems linked together to call into vintage telephones and switching equipment, You could even connect your circuit you built into asterisk using a Gateway, Then configure Asterisk to dial onto the circuit, dial a number and connect a call. Asterisk can do Everything Analog & everything digital, It's awesome!

  • @larrypriest5789
    @larrypriest5789 5 ปีที่แล้ว

    amps matter not volts

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว

      You can't have amps without volts.

    • @larrypriest5789
      @larrypriest5789 3 ปีที่แล้ว

      @@gregm.857 my point was that a 10000 V charge with 1 amp will not really hurt you but a 12V charge at 100Amps will fry your - toast.

    • @gregm.857
      @gregm.857 3 ปีที่แล้ว +1

      @@larrypriest5789 I'm not sure I understand why you made the comment in the first place,
      and I surely do NOT agree with your conclusions.
      10,000 volts will overcome your skin resistance and will go through
      your body. It takes only 100mA (0.10 amps) to kill a person. So
      10,000V and 1 amp certainly WILL hurt you! The usual cause of death
      is ventricular fibrillation where the current causes the heart to stop
      beating normally. It also usually stops respiration so asphixiation
      is a possibility, and at 1 amp there will be a lot of burned tissue.
      On the other hand, 12V is not enough to overcome normal
      resistance of dry skin, although if your skin is wet with perspiration
      (basically salt water) or you're standing in a puddle of water then
      12V will go through you. And 100 Amps literally might boil some of
      your internal organs due to resistive heating.
      If you want a simple experiment, use your car's electrical system. It
      is all negative-ground. So first put your hand on the positive
      terminal of your 12V car battery ... you won't feel a thing. But if
      you pull back the insulating cap on one of your spark plugs and put
      your hand on the connector inside (around 12,000 V or more) you
      will get a hell of a shock. And BTW I do *NOT* suggest doing this
      because it *MIGHT* be lethal even if you are not grounded.
      The situation that you said "will not really hurt you" has 10,000 V
      times 1 A = 10,000 watts of power. The situation that you said is
      worse has 12V times 100 amps or only 1,200 watts. So your "safe"
      situation has eight times more power and can potentially cause eight
      times more damage.
      I definitely do NOT agree with your conclusion.