Introduction: Convert Your Old Phone to a Remote Switch
Ever wondered what to do with your old basic phones? The advent of a smartphone in last decade made all the basic phones obsolete. Even though they had good battery life and decent look they are less when compared to big smartphones which have big screens and lots of features. Even I had lots of these phones lying around. I did this project long back i.e 5 years back when I was in 11th grade. Here I did slight advancement when I saw this old project. In this instructable, I'll use an old basic phone as a remote switch which can be turned on and off from practically anywhere in the world. ( P.S: Where there is cellphone network)
In India, the power supply is not 24x7 in many rural areas. Farmers in the rural area have to supply water to their fields consistently otherwise there might be the loss of crops due to water shortage. The fields are situated far away from their houses. Therefore this project aims to provide a solution for switching pump set remotely to help farmers. But this can be used to switch anything.
Step 1: Get the Parts
1. Old basic phone (I'm using legendary nokia 3310)
2. Soldering Iron
3. Wires
4. Arduino Nano ( Any microcontroller is fine)
5. A relay module (5V 10A)
6. Some LEDs
7. 16x2 display (optional)
8.Perf board
Step 2: Disassembly
Now you need to disassemble your old phone so that you will have access to the vibration motor connections.
I have attached a video of disassembly of Nokia 3310. But the procedure will be same for almost all basic phones.
Open one by one till you reach the main PCB. There you can see a vibration motor inside.
Step 3: Vibration Motors Inside
Vibration motor: It is used to provide haptic feedback to the user when a message or call comes. In vibration motors, there are two types,
1. Coreless motor with an unbalanced weight on the shaft. This results in change in moment of inertia resulting in wobbling and hence the vibration.
2. Coin cell type vibration motor which is sealed.
We have to find the connection points of vibration motors.
And solder these points with 2 wires for extending it. Pretty much every basic phone has a vibration motor either of two types.
Step 4: Connecting It to Arduino
Connect these wires to one of the GPIOs of Arduino. Here I'm using pin number A0. And negative pin to ground. LCD connections are as usual.
Relay module signal pin to pin number 4 and VCC, GND to Arduino's VCC and GND. You can use jumper wires for the connection here I have made a perf board circuit by soldering all components.
Step 5: Upload the Code.
Here I will read the analog port and look for a high signal. And switch the pins accordingly. I have written everything in comments and code is self-explanatory. Whenever it reads a certain voltage at analog pin it activates the switch. This switch can be deactivated by again calling or by sending an SMS.
Attachments
Step 6: Working Video.
Here I have attached a working video how the whole process works. I hope you enjoy recycling your old phone for a good purpose.
Applications of this project are following:
1. Actuation of a pump set in an agricultural land
2. Switching your room heater before going home.
3. Switching your water heater for bathing
4. Turning off the main switch of your home remotely.
And many more. Let me know if you guys find out anything else.
The best part is you can trigger these switches from any part of the world where there is network access.
Thanks a lot for reading.
Don't forget to vote in contests.
Step 7: My Old Design
I just wanted to show my old design of switching circuit. Back in those days i.e when I was in 11th grade I didn't have access to a computer and I never knew about microcontroller. Everything was analog. I have uploaded a video about my switching mechanism. Here I had used a DC motor to get the signal from the phone. When call or message comes this will rotate the motor in one direction and motor's gear rotates a rack of gear which presses a soft push button which I had extracted from a DVD drive. When the pushbutton is pressed it completes the circuit leading to the switching on of small DC pump set (Extracted from Car's wiper water supply).
This supplies water to the field in my demo.Then a water level controller circuit based on opamp senses the moisture level and when it crosses the threshold, it used to spin back the DC motor in other direction releasing the push button. This was the total control system I used in my older project.

Participated in the
Pocket-Sized Contest

Participated in the
Microcontroller Contest

Participated in the
Trash to Treasure
24 Comments
4 years ago on Step 1
Can you send me the design(circuit diagram) of this project?
Question 4 years ago
Looks nice! if anybody calls that particular number, it will switch ON. or only from particular number. My understanding is since you are using vibration motor thats triggered every time a call comes or SMS is received. More over can i find if my motor is switched ON or OFF. Get the current state of the switch if thats switched ON or OFF.
Answer 4 years ago
Yeah. I will work on those things. Thanks a lot for suggestions.
4 years ago
Great Project!!! and truly useful, which is something of worth, and not so often in the Arduino-like world! Congratulations!
Reply 4 years ago
Thanks a lot for your words. This motivates me write more
4 years ago
Exactly how IED's are set off.
Reply 4 years ago
Oh. I didn't know that.
Reply 4 years ago
Hate to say I was thinking the same thing when I saw this. Also, I am absolutely positive that Vishwas Navada was not thinking along those lines, or he wouldn't have even posted this. Let's try to keep our heads just as clean, right?
4 years ago
Very nicely-done, sir! I'll vote for you!
Reply 4 years ago
Thanks a lot for your response
Question 4 years ago on Step 6
connection to actual motor?
Answer 4 years ago
Yeah. That was my old mechanism with gears and all. But you can do that with a microcontroller
Question 4 years ago
Forgive me if I misunderstand, but wouldn't you have to pay for service to the phone?
Answer 4 years ago
Yes. U just need to have a SIM card and you can give miss call which won't cost you anything
4 years ago
Interesting project! Will try it out and let you know. Great job! Keep these interesting posts coming.
Reply 4 years ago
Thanks a lot.
4 years ago
Basic idea is great! Since we do not have a feedback on the switch status and as there is likelihood of false trigger based on calls not made by us, I suggest you include a time sequence. Something like, 2 calls in 2 minutes is ON and 3 calls in 2 minutes is OFF. Thanks for sharing!
Reply 4 years ago
Oh. That's a good idea for feedback. Thanks a lot sir.
4 years ago
this is truly great, th anks for sharing!
Reply 4 years ago
Hey thanks a lot for your good words.