Call Me! Rotary Telephone + Arduino Escape Room Puzzle

[@RogerLeitch]

I used to work in Telecoms and wired many of these phones. The normal power supply would have been 50 volts over the 2 line wires. Ringing was 75 volts 25Hz ac. The line loop resistance would be anything from 200-1200 ohms. The 4 wires were for line, bell and anti tinkle or earth. If there were more than one phone, the bells were wired in series. While dialling, one of the dial contacts stopped you hearing clicks in your ear, another was used to prevent the bells on other phones tinkling. Dialling was 1-10 impulses (circuit breaks) at 10 per second, followed by a pause (300ms?) The phone internally had a number of tags that were connected to the circuit, various switched and the handset. They could be set in different configurations for different uses. It should be possible to just rewire it so that 2 wires in the line cord connect to the handset receiver and another 2 connect via the Switch Hook and dial contacts. There are circuit diagrams on-line.

[@PlayfulTechnology]

Roger Leitch Great information - thankyou!

[@RogerLeitch]

I bought all the bits for this rotary phone project, but didn't get to make it yet. blog.adafruit.com/2016/07/04/hack-a-rotary-phone-to-make-and-recieve-calls-arduinomonday/ There are some similarities - detecting dialled digits. I did get around to making a project using RFID cards, which used the SPI interface. This was a door access control system. These used a normally on electromagnet on the door. I used the opto-isolater and relay module circuit, but found the normally closed relay contacts failed open circuit after a few months. Went solid state and used a darlington transistor to directly drive the magnets. Single 12volt K80 supply (the built in relays failed) and a 7805 voltage regulator for the Arduino. I like the escape room ideas, so may adapt them for use at a fete for fundraising. (I used to have a fake safe - turn a dial, try the handle, if it opens win chocolate or set off an alarm).

[@manyshadesofbrown]

This is turning into one of my favourite KZbin channels

[@milapravda3916]

Well done! I am going to do some experiments thanks to your tutorial. Thank you for sharing your project.

[@IndrekL]

What happens if you start dialing while music is playing? Wouldn't it short PIN 9 to ground and possibly kill your Arduino?

[@kineticpaintings]

Thanks for making this video. I'm designing a project which needs just what you've done; a phone that plays back messages when you dial different numbers. Thank you

[@Crackeditnc1]

Once again, a great tutorial! This exact project has been asked about many times in the Escape Room groups on Facebook.

[@sergeynersesyan7340]

I have made this for my escape room. Thanks a lot

[@sandro-here]

Awesome project! Will attempt to hook it to zigbee/mqtt and use it for a smart home controller.

[@KB-yy7zt]

Best phone hookup I have seen. Have to find a phone in the U.S. and see if it works. Now can you make the phone ring?

[@PlayfulTechnology]

I believe that the final wire I didn't use (the blue one) is the "bell" wire, used for activating the ringer. However, certainly here in the UK, that requires a 50-60VAC current to activate, so I decided not to use it for this project. It wouldn't be too hard to place a small motor inside the phone that rang the bells on a lower DC current though!

[@MrBobWareham]

Well done you should never take apart an old telephone we had one when I was young it's like people converting old oil lamps to electric just wrong anyway loved the video, your very clever loved the Maglock part that dropped on the floor

[@Opa10]

Really good instructions and very understandable for a newbie like me. Always wondered how to fix something like this.

[@DawnsRage]

Is there anything I should avoid when looking for a phone? I am working on a period game and am looking to get a vintage-style 20s rotary dial phone.

[@politicassocialesugtsevill7776]

Thank you so much. I used and Heraldo Telephone from Telefonica España. The speaker didn't work and I didn't have time to solve it, because I had to open my Escape Room, but the dialer opens the door perfectly.

[@dancrocker8292]

Hi, great video. I am beginner and hoping you use this as part of a party I am doing. What did you use to splice the phone cable? The phone cable is so thin, I tried using some B connectors to connect the green and red cables to my jumper leads but it doesn’t seem to register :(

[@davidkempton2894]

Very interesting. I really liked your code explanation. Thanks!!!

[@flooplambada]

Super interesting and helpful. Thanks for the video!

[@MightyMicrobes-]

Is there a way for it to detect when the code is inputted wrong and make it say a warning message on the phone?? Maybe even after 3 times it shuts the power off, until manually restarted?

[@peterandreasen4649]

Hi, If you wanted to have player call 2 numbers to trigger other maglocks would you need a relay for each trigger?

[@lockdownescaperooms]

Hi. Would it be possible to combine this with the 4x RFID Tag game and instead of just audio being played, it would play a video file on a screen?

[@Magma-uw7yo]

How do you connect the phone with the board ? I'm beginner I don't know wich cables is used

[@logsil2012]

I've been working on this for a while. Everytime i dial a number it just repeats "Receiver Lifted, Receiver Replaced" over and over for the amount of pulses. Any idea what I'm doing wrong?

[@davidkempton2894]

Got the music playing now from the SD card. Probably worth pointing out that level shifting may be required to get the Arduino to talk to the SD card. Also the music must be mono 8-bit .WAV files , sampled at 32KHz or slower. And wav file names should not have more than 8 characters!

[@freespirit1177]

David Kempton , a big thank you to you! I was just getting static, when I converted my wav file to 8 bit it started working. Happy days :-)

[@davidkempton2894]

Russell Hardman Really glad that solved your problem Russell. It's a neat little project isn't it!

[@romanstafl4381]

Thank you! this helped me as well!!

[@thepvporg]

You can eliminate bounce problems by an analogue method and you then can devote the code to just the logic, not evaluating bounce issues.

[@PlayfulTechnology]

Yes, you can. Personally, I find that including debounce procedures in the code makes the problem (and the solution!) more explicit and easier to understand, but you can certainly do it using a purely hardware solution instead if you prefer.

[@charlottedewaal5204]

would I be able to try this experiment with an office phone from the 90s?

[@Tehral]

it th eisolator the same as the optocoupler? I am getting my parts from banggood and I only find those

[@romanlowen8001]

Really clever how you insulate the circuits, But in my opinion you use to much single parts. There is a option to use a single device which does all the operations on it's own. Check on KZbin DigitalTechUSA or The Lockey escape rooms in UK

[@damianleszczynski2463]

WOW! It's great! How is the phone powered? The video shows a phone cable connected to a module next to the arduino - what is it?

[@PlayfulTechnology]

The phone does not need any power - if you mean the thing slightly down and right from the Arduino, that's just a line of terminal blocks to allow the cables to be easily plugged into the breadboard, e.g.: c1.staticflickr.com/9/8723/29338211736_27581c12ca_o.jpg

[@damianleszczynski2463]

Thanks!

[@jakejohnson875]

Is there anyway to be able to do different length of digits? In the code its defined by "const int numDigitsInPhoneNumber = 5;" What would be the best way to have it be able to dial different length numbers eg; 999, 12345, 12345312 TIA

[@lockdownescaperooms]

In the CONSTANTS; this line of code can be altered: const int numDigitsInPhoneNumber = 7; Change the 7 above to any length you want

[@owen7671]

Just created my first home Escape Room using ideas from your sequence lock - Thank you! Your videos have been extremely educational. On this rotary phone project, would it be easy to have a dial tone sound play when the receiver is first picked up that turns off when dialling a number?

[@music4note]

Amazing Short question my phone has 4 cables How do I know which is which :S?

[@music4note]

The colors are Brown White Red Blue Blue and black share the same powersocket pin

[@davidkempton2894]

Did you use an original unconverted 746 for this project? If so do you think one of the new 746 phones that is designed to work on the modern phone network would also be compatible with your project? If fear not since I believe that it is only two wires now rather than four.

[@PlayfulTechnology]

I'm using a completely unconverted 746 which I bought off eBay that had come from someone's aunt's loft I think, where it had lay for many years! I'm not familiar with "new" 746 phones, but if they use tone dialling I'd use a different approach instead - using a PAPT and a private PBX server running on a Raspberry Pi, say - to intercept and act on the DTMF tones instead of listening to rotary pulses.

[@davidkempton2894]

Thanks!

[@duncanx99]

@@PlayfulTechnology That increases the cost considerably though... Do all BT phones come with the BT Connector, or are the later ones RJ-11? ( (I left the UK a long time ago!)

[@PlayfulTechnology]

@@duncanx99 UK phones use 431A connectors, not RJ11. As for cost for my other solution, a Raspberry Pi is around £30, and a PAP2T is around £20. More expensive than this approach, yes, but also more powerful and feature-rich (and doesn't require any hardware modification)

[@PlayfulTechnology]

I started a new tutorial series explaining this approach - first two videos are now online here: kzbin.info/www/bejne/oZOydXuYf954jpY

[@manuosiris4291]

What is that lock??

[@tomhurst9629]

Hi there, struggle to get mine to work at the moment. When the handset is lifted the serial monitor doesnt have it registering as lifted and then when the i pull one of the numbers around it then displays reciever lifted and when the dial spins back it displays reciever replaced. It only does this when the actual handset is off the hook. Any thoughts on what is being messed up here? Thanks

[@PlayfulTechnology]

Tom Hurst Have you tried swapping over the phonePin and hookPin?

[@tomhurst9629]

Yeah and that partly solves the issue of registering the phone off the hook but then every time you dial a number it just flickers the reciver lifted/returned without counting dial numbers. On startup i get this on the serial montor Serial connection started Setup Complete (handset lifted at this point) Receiver Lifted Receiver Replaced Receiver Lifted Receiver Replaced Receiver Lifted (handset now in the air. pull number 1 around and let go) Receiver Replaced Receiver Lifted Receiver Replaced Receiver Lifted Receiver Replaced Receiver Lifted

[@PlayfulTechnology]

Tom Hurst Hmm. Do you have access to a multimeter? And what sort of phone are you using? Have you got the white wire connected to GND?

[@ClocktowerTom]

Playful Technology could you drop me an email to info (at) adventure vault.co.uk thanks. [e-mail]

[@hiteshpatel-hg7cz]

I'm stuck at this stage. Were you able to solve this?

[@yourNAMEwasTAKEN]

What type of maglock is that?

[@wqwwqwqqpoppopoo]

I think the general term for it would be "electric cabinet lock". If you search for "12v cabinet Lock" on Amazon you should see some similar ones for sale (at least if you live in the USA)

[@NoviceRobot]

Nice