DIY security alarm with mobile phone. GSM Alarm from an old mobile phone. Video on how to make a cell phone alarm with your own hands

Hello Lifehackers! We continue to broadcast interesting topics from the weekly electronic magazine. In the magazine we write about useful gadgets, amazing inventions, look a little into the future, and also give advice of varying degrees of usefulness. Subscribe to the magazine and read the entire content, but first read the tip on how to make an alarm out of an old phone. For example, automobile.

In a modern city, and not only in the city, very often you have to leave your car unattended in unguarded parking lots, or simply on the street out of sight. In this case, even if the standard alarm goes off when the car is opened by an intruder, you will not hear it.

It would be great if a car, when you try to steal it, would call your cell phone!
Why not! You just need to teach your car to use a mobile phone.
Let's do this with step-by-step instructions.

Surely you have an old mobile phone, or even two, lying around somewhere in a pile of junk.

Step 1

We take a phone that has a speed dial function (this condition is mandatory).

Step 2

Let's disassemble the phone. We cut a hole on the keyboard above the button with the number “2” and solder two wires to the contact pads of this button (to simulate pressing the button when the wires are shorted). We collect the phone.

Step 3

We connect the battery to the phone using a pair of wires, observing the polarity. In parallel, we solder the output of the car charger.

Step 4

We buy a new SIM card and install it in the phone.

Step 5

We write down your mobile phone number, activating its speed dialing in the car phone. In the car phone settings, turn off the ringer and indication.

Step 6

We connect the charger to the car battery using two wires, observing the polarity.

Step 7

We connect the wires coming from the button through the additional switch to the driver's door limit switch (the additional switch is needed to quickly disable the security function).

So, the alarm is ready!
When you open the door, a call will immediately come to your mobile phone, and you will realize that someone has climbed into the car. In addition, you can determine its location using the signal from your car phone.

Such alarms can work not only on cars, but also on any other objects, such as cottages, garages, etc. You just need to consider where to power the device.

However, not in all cases an alarm can help.

What would you use an alarm like this for? It can also be used as information system, calling, for example, when someone opened the refrigerator door.

We welcome comments and ideas for protected objects, even the most crazy ones.

We also recommend reading in our magazine about a minicomputer for $25 and what it can do, about a massage pen, and about which phones behave in cold weather.
It will be even easier to go straight to our magazine and not miss anything.

The magazine contained an article by the author Lyzhin R. “GSM security system for a summer residence.” There it was proposed to use a regular inexpensive cell phone as a GSM security alarm. I want to say that the “offer” is very tempting, because even the cheapest GSM security device costs an order of magnitude more than the old one cell phone. In addition, the author has found how to connect to a cell phone in the simplest way, which does not require any intrusion into its circuitry. And at the same time, the cell phone itself becomes a security device. To be honest, previously I had no idea about such capabilities of cell phones, because everything that I was able to read earlier on this topic required changes both in the circuit of the cell phone itself and required the need for an external electronic unit of the security system.

I needed to make a security system that responds only to a reed switch door position sensor. The author of the above article suggested in this case using a limit switch, the normally closed contacts of which should be connected parallel to the button of a wired headset of a cell phone. But this didn’t quite suit me, because the limit sensor is not designed to work in conjunction with front door. It does not take into account both the play in the door frame and its open contacts exposed to atmospheric and other influences. It is not for nothing that for these purposes, security devices use special reed switch “security detectors”, consisting of two halves - one with a reed switch inside is placed on the door frame, and the second with a magnet inside, on the door itself. At the same time, the design of the detector allows play in the door system within the limits of up to 2-3 cm, which is very important, especially if the room is wooden (the wooden opening “walks” depending on humidity and temperature), and natural wear and tear of the door can lead to “movements” .

But the fact is that the reed switch security detector works to open. That is, the door is closed - the contacts are closed, the door is open - the contacts are open. Here the opposite is required. Therefore, we had to make an “inverter” from a low-power relay with a 5V winding.
The figure in the text shows a diagram of my version of the GSM security alarm. The system consists of an old Philips E-1500 cell phone with its own wired headset and charger, an IO-102-14 security detector and a V23092-A005 electromagnetic relay with a 5V winding and switching contacts.

You only need to “mock” the wired headset and the charger cable. For a wired headset, you need to open the button housing and solder two mounting wires to its contacts. The charger cable needs to be cut and the red and black wires pulled out.

Relay coil K1 is connected between the red and black wires through the security detector. And in parallel with the headset button, normally closed relay contacts are connected.

Now, when the door is closed, the SG1 contacts are closed and the relay winding receives current from the charger Z.U. Relay contacts “11” and “12” open. If the door is opened, the contacts SG1 open, the current to the winding of relay K1 stops flowing and its contacts “11” and “12” close. Since they are connected in parallel to the cell phone headset button, the phone rings the number entered into its memory. This serves as a signal that the door has been opened.

Now about the cell phone settings, this is written in detail in L.1, but let me repeat it briefly.
A Philips E-1500 cell phone is used. You need to install the SIM card only in the SIM2 slot, while leaving the SIM1 slot empty. On this SIM card you need to save the only number that the cell phone will call when you open the door, save it under the name “1”.
Next, you need to enter the “settings” menu, then “profiles”, and select “mute”. Then enter the “calls” menu and select the “advanced” item, then enter the “answer mode” menu and select the “automatic” item.

Now you need to block incoming SMS. This cannot be done from the phone, so you need to contact your operator about this issue mobile communications so that the “incoming SMS” service is disabled. Or do it yourself in " personal account» on the website of the telecom operator whose SIM card you are using.

The only setting on the receiving cell phone (to which the security device will call) will be to enter into the “contacts” the number of the cell phone installed at the protected location and assign it an appropriate name (for example, “Barn Security”). As soon as the door to this barn is opened, your cell phone will ring and the message “Barn Security” will appear on its display. There is no need to answer the call, and everything is clear.

If there are several places that need to be secured, you can purchase an appropriate number of old cell phones and make several of these security devices. Accordingly, in the “contacts” of your phone there will be “Barn security”, “Garage security”, “Pantry security”, etc.
The choice of a suitable cell phone to work as a security device is written in detail in the article already mentioned above (L.1), but let me repeat it briefly.

First of all, the phone must have a wired headset, and it must start dialing the number stored in the memory with one press of the headset button.

There should be an auto-answer mode (or “hands-free”, “car”, etc.).

Many inexpensive cell phones meet these requirements. But there are also those who do not respond to the headset button, or react incorrectly, and to dial a number you need to press some buttons. These cell phones are not suitable for use as a security device. All this needs to be carefully checked “live” when buying a cell phone, because the instructions do not always reflect all the possibilities in sufficient detail.

Tarantsev N.I.
Literature:
1. Lyzhin R. “GSM - security system for a summer residence”, w. Radioconstructor, No. 3, 2016, pp. 20-23.

If you have a summer house, a car garage or a country house, then sooner or later you will think about means of protecting your property. The most popular means of protection nowadays is GSM alarm system. Now there are many types of GSM alarms from various companies. The only deterrent to purchasing a GSM alarm system is its price. For example, simplest GSM Magnum MH-825-03 GSM alarm system costs about $150. Based on this, if you need to secure your garage, cottage and home, then you will have to spend a lot. So that our readers can save a lot of money, we have prepared material in which we will describe the creation of a homemade GSM alarm system with our own hands. This alarm will based on a regular mobile phone, which has been idle for a long time.

We assemble a simple alarm system based on a mobile phone for a summer house or country house

The first DIY alarm based on a mobile phone will be very simple. To assemble it we need the following Components:

• old mobile phone;
• reed switch;
• standard Charger for battery;
• long wire;
• soldering iron;
• solder;
• magnet;
• additional SIM card.

Any old one will do for this alarm. push-button telephone. You can even use old models like Nokia 3310. Principle This type of alarm is based on the speed dial from the button to which the sensor is connected. That is when the sensor is triggered, the phone dials a number, configured in speed dial. Therefore, the first thing we will do is set up our phone to quickly dial the number that will receive a call when the sensor is triggered. In our case, the speed dial button will be the ninth button. You should also turn off the ringer and vibrator on your phone. It’s also worth considering whether we should use a charger for our phone or leave it running on a fully charged battery.

You should only leave your phone on a charged battery if it can hold a charge for about a month.

Below is a diagram of the assembly of such an alarm for a cottage or home.

The figure shows the connection diagram Nokia phone 6150 k reed switch. To connect the reed switch to the Nokia 6150, you need to disassemble the phone and carefully solder the wires to the contacts of button nine on printed circuit board(Speed ​​dial button). After this, the magnet and reed switch are attached to the door. The scheme works like this: when the door is opened, a signal is sent from the reed switch to the button, as a result of which the phone dials the specified number in speed dialing. The reed switch itself is a magnetic sensor, somewhat reminiscent of a diode.

In the same way, as shown in the diagram, you can connect a self-assembled GSM alarm system in a country house, cottage or garage.

Do-it-yourself GSM alarm system with infrared motion sensor for a country house or dacha

The operating principle of this GSM alarm is based on infrared motion sensor, and not on the reed switch. AND The infrared motion sensor is triggered when an object is in its field of view and sends a signal to the mobile phone. After the signal reaches the phone, it dials the number previously configured in the speed dial. The circuit itself of an autonomous alarm system using an infrared motion sensor is shown below.

The diagram shows, as in the first example, the motion sensor is connected to the ninth button.

It is worth noting that the motion sensor itself requires a separate 12 V power supply.

You can use the Astra 515 device as a motion sensor itself.

This motion sensor has a range of 10 meters. For example, if any object falls within this range, the alarm will go off and make a call.

Another feature of this motion sensor is the IP41 protection level, which allows it to operate at temperatures from 0 to +50°C.

It is convenient to use such an autonomous GSM alarm, assembled with your own hands, at the dacha and in a country house to protect their territories.

We assemble a GSM alarm system with our own hands without an old mobile phone

There may be a situation when you don’t have an old mobile phone at hand, but you want to save money on a GSM alarm system. In this case it will help us Arduino board with built-in microcontroller. Distinctive feature What makes this board stand out is its low price and functionality. In our example we will use the board Arduino Uno, which costs about $4 (depending on modifications). For the basis of this example, we will take the article “GSM Home Alarm V1.0”, authored by Hugo Gomez. You can find this article on the official website www.arduino.cc of the Arduino project. To assemble our alarm system with our own hands, we will need the following Components:

• the board itself with the Arduino Uno microcontroller;
• GPRS Shield V2.0 - GSM module;
• power supply 12V@2A;
• ultrasonic distance sensor HC-SR04;
• connecting wires;
• bread board;
• SIM card.

The cost of all components of such an autonomous alarm system will be $35, which is still much cheaper ready-made solutions. Principle the actions of this alarm are based on an ultrasonic sensorHC-SR04, which detects the difference in distance and sends a signal to the mobile phone. For example, if a person gets into the sensor’s measurement area, the sensor will record a distance less than the intended one and the Arduino Uno will send a signal to the mobile phone. The measuring length of this sensor is 4 meters and the viewing angle is 30 degrees. Thanks to these characteristics, the sensor can be used at home, in the garage and in the country.

To assemble this alarm, the first thing you need to do is install a SIM card in the GSM module.

You should also disable the PIN code on the SIM card in advance. Now let's connect all the components with wires according to the diagram shown below.

The assembled GSM alarm will look like this.

In order for our GSM module GPRS Shield V2.0 worked in conjunction with Arduino Uno, we need to download the library SIM900. You can download this library at this address http://www.gsmlib.org/download/GSM_GPRS_GPS_IDE100_v307_1.zip. After downloading, install this library. In a further step, we will need to open and edit the GSM.cpp file, which is located in a file in the SIM900 library folder. The point is that GSM GPRS module Shield V2.0 in conjunction with Arduino Uno uses pins 7 and 8. Therefore, open the GSM.cpp file and correct the values ​​of lines 27 and 28 to:

#define _GSM_TXPIN_ 7 #define _GSM_RXPIN_ 8

#define _GSM_TXPIN_ 7 #define _GSM_RXPIN_ 8

Now we need to open the GSM.h file, which is also located in the library folder. In this file we need to comment out lines 20 and 45, and correct 8 to 9 in line 44.

We've sorted out the module, now we can go directly to our alarm code. The code itself can be downloaded from this link https://create.arduino.cc/code_files/47730/download. In line 11 of the code you need to replace “XXXXXXX” with phone number, to which the signal will be sent. By uploading the code to the Arduino Uno, you can test a standalone GSM alarm system. To do this, connect power to it and open the port monitor. The GSM module itself may take a long time to register on the network, where you will see the message “ Waiting for Network Registration". If registration in the network is successful, the alarm can be tested. To do this, move your hand over the operating area of ​​the HC-SR04 sensor, after which you will see a message in the port monitor about the data taken from the sensor. In addition to messages in the port monitor, a call should be received to the phone specified in the code.

From the example it is clear that a person who has already worked with Arduino Uno can easily assemble a similar GSM alarm system with his own hands. In addition, such a warning system can be modified. For example, install several HC-SR04 ultrasonic sensors on it. You can also add an infrared sensor to this alarm system, the price of which in Chinese online stores starts from 50 cents. You can also add temperature sensors to this warning system, which will notify the owner of a house, garage or cottage in the event of a fire.

Let's sum it up

In this material we have collected everything simple ways DIY GSM alarm assembly. In addition to methods for assembling a GSM alarm with your own hands from an old phone, we described a method for assembling an inexpensive system using an Arduino Uno board and a GSM module, which acts as a replacement for a mobile phone. Also on the Internet you can find examples in which a push-button mobile phone is used instead of a GSM module. This alarm is similar to the examples described above, but thanks to the Arduino Uno it has much higher functionality. We hope our material will help you assemble a GSM alarm system with your own hands, while allowing you to save a lot and protect your garage, house or cottage.

Video on the topic

We are talking about the use of a security alarm installation scheme in which, in the appropriate situation, automatic mode A notification will be sent to your mobile phone. The market offers many such solutions.

As a rule, we are talking about installing a complex of various security sensors that will give a signal in case of unauthorized entry.

The sensors used can be:

• motion sensors;
• door opening sensors;
• window opening sensors;
• smoke sensors, carbon monoxide distribution;
• flood sensors;
• gas leak sensors;
• perimeter control sensors;
• other sensors.

Note that the alarm system not only deals with countering illegal entry, but can also solve other problems (early warning of fire, flooding, gas leaks or other issues).

One or two control panels can be installed, communication with a security company to call its employees.

Some GSM systems can be supplemented with functions that relate not to security functions, but to the Smart Home system. In this case, you can use your mobile phone to turn on or off certain electrical appliances in the house.

Attention-attracting systems (for example, a siren or a special spotlight) may also be additionally provided.

The system can be equipped with a remote control.

The peculiarity of this type of alarm is that in its simplest version it can be made independently. This choice seems reasonable when it comes to protecting a garage or personal car.

Principle of operation

A special compact control device is provided, which is actually a receiving and transmitting device, which is connected to the mobile communication system and has its own SIM card and, accordingly, a telephone number.

To turn the alarm system on or off, an SMS message of a strictly defined type is sent to it. When certain events occur, a message is sent from the same number with information about what happened.

As a rule, from one to three mobile phones are notified, depending on the type of security system.

Various security sensors are connected to the control device. Their connection itself can be carried out either using wires or wirelessly.

How to make and install a GSM alarm yourself

Of course, in this case we are talking about performing basic functions. Nevertheless, the system made in this way is, although simple, but at the same time quite reliable security system.

Required materials and tools

To get started, you need the following components.

1. The main element of the assembled circuit is an old mobile phone. It must be push-button. Touch is not suitable for our purposes. It must also have the property that it must provide abbreviated dialing.
2. You need to prepare a soldering iron. It would be helpful if you already have experience with this tool.
3. Reed switch. What is meant here? This is the name of a switch that opens an electrical circuit under the influence of a magnetic field and closes it when this influence stops.
4. Magnet. It is needed to influence the reed switch.
5. Wires.
6. Regular switch.

How to install this system

1. First of all, you need to install an abbreviated dialing number(meaning the number to which the notification should be sent).
2. Next you need to prepare the keyboard. To do this, remove the top layer and solder the wires to the key used for short-term typing in such a way that when current passes, an imitation of pressing the corresponding key is performed.
3. This is what we are talking about here. When you press the button, the contacts close and the button operates. If you solder a wire to both contacts and connect these wires somewhere outside the phone, this will lead to the same effect as pressing a button (the programmed number will be dialed and you will receive a signal from the security system).
4. We install the reed switch on the door frame, and the magnet to the place on the door leaf that will be adjacent to it when closed. Let's run the wires to the reed switch. Thus, when the door is opened, the reed switch will work and the corresponding bell will ring.
5. You need to install a switch on one of these wires. After all, the system must operate in the period of time when it is needed. At other times everything should be turned off.
6. Don't forget that the phone will gradually discharge. Therefore, we will make sure that it is constantly recharged using its own charger, which will be constantly connected to the network.
7. Do not forget that although we manufacture the system ourselves, similar to the circuit connecting the reed switch, you can supply an industrially made controller with various sensors connected to it. If desired, this can significantly increase the protective potential of such a security system.

Some additional notes

Button manipulation can be more sophisticated. So, you can operate the buttons in the same way to turn the phone on or off in order to save energy. This point may be relevant in a situation where it is impossible to ensure constant charging of the phone. For example, in a garage or when installing a security system in a car.

It is not advisable to use a SIM card that can be called.

Let's tell you more about connecting to buttons. It looks like this. The first picture shows the surface when removing the outer shell of the keyboard.

Shown is what it will look like when viewed from above. Next we see silver metal caps opposite each button. They allow current to flow when a key is pressed. Solder one wire to the ring contact, the other to the base. Then we put everything back together. The wires are connected.

Sensors here can be used not only those that operate on the basis of a reed switch. The main principle here is that a security breach should result in the closure of the relevant circuit. We can even talk about various kinds of simple mechanical devices suitable for this purpose.

Efficiency

Of course, the simplicity and low cost of installation determine the insufficient degree of efficiency of this type of system. But still, in some cases they can be useful and irreplaceable.

In any case, an alarm system is better than no security at all. In addition, for some applications (garage security, for example), this degree of security may be quite sufficient.