DIY Spy Phone




This project is good for learning the basic idea about electronics and its fun to do. The build is very easy to make and safe to use (no hazardous parts).

The idea about spy phone is that it looks like an ordinary phone. I made this instructable just for the spy contest (and have thousand ideas to come) . challenge in this project is to make everything small as possible. You can use in this project any phone you have (including mp3 players and everything that is small and mobile). The thing about the phone is that is actually a super sensitive hearing device that you can use everywhere and no one will ever know what you hear. Now if you build this, i'm not responsible for any action you use this device for.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: This Is What You Will Need:

obviously you will need an old phone(or new if it's not about cash) or a dummy phone. you will probably find an old phone from your own home/ ask your friends that do they have any or buy from Ebay, second hand store. You can find also a dummy phones from internet, google is your friend.

The components that you will need are:
The amplifier IC -TDA2822M
Few resistors- one about 30Kohms for the microphone and 4.7 ohms
four condenser- one 0.1 uF, one 10 uF and two 100 uF.
Battery (i used a phone battery because its small and easy to recharge on another phone. it has 3.7 volts and 600mAh so it will last. keep in mind that the amplifier needs only 1.8 volts to work and maxes out on 15 volts)
small switch
3.5mm audio jack
microphone (smallest that you can get)
and something to solder the parts to
and some wire
and tape
... i think that's all. use your imagination if needed

Tools that you will need:
sharp knife to cut the plastic if needed
Small screwdriver
Soldering iron

Ps. If you have the chance. do this project to surface-mount (i'm not sure about the right word) and use the smallest parts possible.

Step 2: Clear the Phone From the Old Parts

Just screw all the screws from the phone and "empty" it. meaning that take everything out from it. leave the plastic parts only (keep in mind that the phone has a small microphone that you can use. i didn't :D)
also if you have an battery in the phone that is in some sort of case ( like in this phone) empty it too. But be careful not to puncture the battery inside the case.
After you have removed all the parts from the phone it should look like in the last picture.
(by the way. Thank you instructables for the leatherman juice s2!!. It is very handy tool to use :))))

Step 3: Building the Circuit

First about the TDA2822M chip:

The TDA2822M is a monolithic integrated circuit in
8 lead Minidip package. It is intended for use as
dual audio power amplifier in portable cassette
players and radios.
very handy chip in use and low cost

In this project its only one channel (mono) because i didn't have the room to add few capasitators more. the audio jack makes it for the both channels but from the chip its only on one channel (you can make stereo by using both channels and using two microphones or bridge the channels)

Now when you have the circuit board ready. start soldering the parts on to it by copying the layout from picture 3 (if you have something to say about the layout please do say it. i'm not perfect about it and it might have lots of work to do about it, but for me it works just fine).
In the layout at the speaker part you put the audio jack.

Remember to fit the circuit to the phone after every added component that it fits in the phone.

Step 4: Battery Installation

I was about to use V23GA battery instead of the phone battery but could not find any. But the phone battery works just fine.
So i mounted the Battery inside the screen lid with the microphone (microphone wires not showing in the picture 2, just trying to see that the battery fits in the lid). If you do the same thing put the text side up so it seems that there is light on the display
I put the microphone to the same place where the phones speaker used to be.

Step 5: Final Touches

So Just push everything inside the phone and hope it fits there. also if you like you can put a button aside the phone so if you press it, its on and if you don't its off. also i put the audio out jack to other side the phone. just drill a small hole where you want it.

Step 6: The_Spy_Phone

And by now you have a working spy phone. now go and secretly listen conversations you   tease your neighbor or do what ever you like. (i'm not responssible of any action  made with this).
Have Fun! :)
Any questions will be answered!.
And most of all
Greetingsfrom Finland!
Stay tuned. Huge project comming in a few months. i have been building it for about half a year. It will include computer, drawing, huge touch screen and also angry birds.
small projects like this one will come soon too.

If interested Check these out too:

How to make a tablet pc from an old laptop


Xbox Hackintosh casemod

Vote For Spy Contest and rate and comment!!!!!

Spy Challenge

Finalist in the
Spy Challenge

Make It Real Challenge

Participated in the
Make It Real Challenge

Education Contest

Participated in the
Education Contest



    • Indoor Lighting Contest

      Indoor Lighting Contest
    • Make It Fly Challenge

      Make It Fly Challenge
    • Growing Beyond Earth Maker Contest

      Growing Beyond Earth Maker Contest

    35 Discussions


    8 months ago

    Or you can just simply install spytomobile app on the target phone


    1 year ago

    Can I use old capacitors and other parts?


    Reply 3 years ago

    This idea is to make a powerful hearing aid to look like a phone...


    Reply 3 years ago on Introduction

    Sure. Why not? This is a example how to do it with basic electronic components. ie. how to make a amplifier.


    Well. It amplifys the sounds around you so you can hear much better. For in this project the headline "Spy Phone" should say something.


    6 years ago on Step 3

    can you tells us which pins of the TDA2822 you used in the circuit ? the numbers of the pins. thank you :)

    2 replies

    Reply 6 years ago on Step 3

    The pin numbers can be seen in the datasheet. just google tda2822 datasheet.


    Reply 6 years ago on Step 3

    Will do :) thanks for the instructable, I plan to try it out in the not so distant future.


    Reply 6 years ago on Introduction

    amplifying the sound around you so you can hear anything clearly and things that you wouldn't hear with normal hearing. "The thing about the phone is that is actually a super sensitive hearing device that you can use everywhere and no one will ever know what you hear." Read the damn thing and then ask questions.


    Reply 6 years ago on Introduction

    you didnt had to be rude....its all electronic ( I read all the post but its to much electronics hehehe) reaally really nice post! I`m thinkings seriusly to start learning electronic . If I do I`ll definitly try these one !


    Reply 6 years ago on Introduction

    The best way to start learning about electronics is to buy a toy electronics test board (the kind they sell at toy stores). Its the best and easyest way to start learning electronics because if you screw up you can easily start again (i always try my builds on the same kind of board before soldering to see if it works). so no soldering there. When you "master" that and think you can go to the next level. try soldering. just solder random components to a breadboard or something like that or try to build something to the board you have allready build on the toy test board.
    You will need:
    decent multimeter. just for measuring voltages etc. and learn that way the use of it. and has got hell lot of information in the future.
    Soldering stuff. don't buy the cheapest you will find. its just pain in the ass. buy something you can change the temperature of the solderer(don't know if a real word.)
    And open mind for anything
    Remember. Start small and go big.

    and remember also. when you get the idea of the components and the idea of electronics. its time to try programming the electronics. if you want i can send you a picture of 8-bit Attiny 2313 test and programming board (yea. you can do knight rider lights with that... so Nothing cool really ;) )