Do-it-yourself mobile phone alarm. Simple mobile phone alarm

We are talking about the use of such a scheme for installing a security alarm, in which, in an appropriate situation, a notification will be automatically sent to a mobile phone. The market offers many such solutions.

As a rule, we are talking about the installation of a complex of various security sensors that will give a signal in case of intrusion.

The following sensors can be used as sensors:

motion sensors;
door opening sensors;
window opening sensors;
smoke sensors, carbon monoxide spread;
flood sensors;
gas leakage sensors;
perimeter control sensors;
other sensors.

Note that the alarm system is not only engaged in countering illegal entry, but can also solve other tasks (early warning of fire, flooding, gas leakage 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 are not related to security functions, but to the Smart Home system. In this case, through your mobile phone, you can turn on or off certain electrical appliances in the house.

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

The system may be equipped with a remote control.

A feature of this kind of signaling is that in its simplest version it can be made independently. This choice looks justified when it comes to guarding a garage or a personal car.

Principle of operation

A special compact control device is provided, which is actually a receiving and transmitting device that is connected to a 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 the incident.

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 can be carried out both using wires and wirelessly.

How to make and install a GSM alarm system yourself

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

Necessary materials and tools

In order to get started, the following components are required.

The main element of the assembled circuit is an old mobile phone. It must be a button. Touch for our purposes will not work. It must also have the property that it must provide for abbreviated dialing.
You need to prepare a soldering iron. It would be helpful if you already had experience with this tool.
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 when this effect stops.
Magnet. It is needed to influence the reed switch.
Wires.
Normal switch.

How to install this system

First of all, you need to set up an abbreviated dialing number.(meaning the number to which the notification should be sent).
Next, you need to prepare the keyboard. To do this, remove the top layer and solder the wires to the key used for short dialing in such a way that when the current passes, the pressing of the corresponding key is simulated.
Here's what we're talking about here. When the button is pressed, the contacts are closed and the button is actuated. If you solder wires to both contacts and connect these wires somewhere outside the phone, then 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).
We install the reed switch on the door frame, and the magnet to the place on the door leaf, which, when closed, will adjoin to it. Let's run the wires to the reed switch. Thus, when the door is opened, the reed switch will work and the corresponding call will occur.
You need to install a switch on one of these wires. After all, the system should work in the period of time when it is needed. At other times, everything should be disabled.
Do not forget that the phone will gradually discharge. Therefore, we will make it so that it is constantly recharged with the help of its charger, which, let it be constantly connected to the network.
Do not forget that although we manufacture the system ourselves, but, similarly 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 operation could be more sophisticated. So, you can similarly act on the buttons to turn the phone on or off in order to save electricity. This point may be relevant in a situation where it is impossible to provide constant recharging of the phone. For example, in a garage or when installing a security system in a car.

It is undesirable to use a SIM card that can be called.

Let's talk more about connecting to buttons. It looks like this. The first figure shows the surface when the outer shell of the keyboard is removed.

Shown is how it will look when viewed from above. Next, we see silver metal caps opposite each button. They provide the passage of current when a key is pressed. We solder one wire to the ring contact, the other to the base. Then we collect everything back. Wiring done.

Sensors here can be used not only those that operate on the basis of a reed switch. The main principle here is that as a result of a security breach, the corresponding circuit is closed. We can even talk about all sorts of simple mechanical devices suitable for this purpose.

Efficiency

Of course, the simplicity and cheapness of the installation cause an insufficient degree of efficiency of such systems. But still, in some cases, they can be useful and irreplaceable.

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

Recently, an acquaintance complained that they climbed into his garage, and there was no way to find out about it. After all, there was no security device in the garage. A dog and private security are also not suitable.

I remembered that you can make a security device from a mobile phone. After all, in phones, the keys are the same normally open contacts, and what prevents these contacts from closing when the garage door opens?

So, an old, but quite working Nokia phone was chosen as a device for protection.

We open the phone. Solder wires to any convenient button. In almost all cell phones, you can use all the number keys except "1" and "0" for a quick call.

In this case, the “4” key seemed convenient to me. In this case, soldering is a delicate task, without special skills it will not work to solder in a quality manner here - you can ruin the phone. We carefully clean the necessary paths, tin.

Solder flexible wires. We exclude short circuit on the case. To do this, you can stick a piece of electrical tape on the metal under the keyboard.

Wires soldered to phone keypad

We degrease the solder, remove the flux. Then we cover the place where the wires touch the board and the place of soldering with rubber glue of the Moment type in order to reduce possible mechanical stresses on the place of soldering.

The wires are soldered, the most responsible behind

We assemble the phone case. After such an intervention, the keyboard will most likely not work so reliably. The keyboard is skewed, some buttons will now not be pressed as easily as before. The case will also not be able to ideally fit the “fat” phone. However, convenience and beauty are useless for such a phone. For aesthetes, I can advise you to solder wires in varnish insulation with a diameter of 0.2 - 0.5 mm. Reliability is what will suffer in this case.

We solder the connector for the convenience of connecting thicker and more convenient wires that will go to the limit switch mounted on the gate. This is what the security device looks like:

A limit switch of any design is connected to the connectors, for example, any of the following series:

The device works in this way. When the garage door is opened (no matter who, the owner or the thief), the contacts of the limit switch are closed. This is equivalent to closing the shortcut button. In my case, this is the “4” button. This button is programmed to call the number of the owner of the garage. If the owner entered the garage, he presses the call reset on his phone, checking the connection will not hurt. Well, if the robber - the owner acts according to the circumstances.

A few little things to keep an eye on.

The phone must be connected to the charger at all times.
The phone screen will light up when you call. This should not attract the attention of an attacker. Therefore, it is necessary to carefully isolate the light emission from the display - for example, place the phone in a box with the screen down.
It is clear that the money on the phone account should always be. But if you do not make a single paid call for a long time, problems may arise. The fact is that some mobile operators have a maximum time for which a subscriber must make a paid call. If during this time (from 3 to 6 months) not a penny is deducted from the account, the number may be blocked and our security system will stop working.
Be sure to turn off the vibrating alert and all sounds on the phone and lower the speaker volume to a minimum - in silence, any sound can alert the robber.
It is desirable, if possible, to limit or disable the receipt of incoming calls or SMS. In addition to possible sounds, this may cause an incoming SMS or missed call message to appear on the screen. And this can block the quick call when the button is pressed.

On the basis of a limit switch that closes when the front door is opened, you can also make another device - a switch for a light bulb. When the door opens, it turns on in the garage (or shed, storage room, utility room). For you - convenience, and for the robber - extra nerves, it can frighten him off or attract witnesses.

Stair switch on impulse relay.…

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 all the content, but first read the advice on how to make an alarm out of an old phone. For example, automobile.

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

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

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

Step 1

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

Step 2

We disassemble the phone. We cut a hole on the keyboard above the button with the number "2" and solder two wires to the pads of this button (to simulate pressing the button when the wires are closed). We collect the phone.

Step 3

We connect the battery to the phone using a pair of wires, observing the polarity. In parallel, 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 the number of our mobile phone, activating its speed dial in the car phone. In the phone settings of the car, 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 an additional switch to the driver's door limit switch (an 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 understand that someone has climbed into the car. In addition, the signal from the car phone can determine its location.

Such alarms can work not only on cars, but also on any other objects, such as cottages, garages, etc. It is only necessary to provide for what to power the device from.

True, not in all cases, the alarm can help.

What would you use such an alarm for? After all, it can also be used as an information system that calls, for example, when someone opens the refrigerator door.

We are waiting for comments and ideas of protected objects, even the most delusional 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 immediately go to our magazine and not miss anything.

Security and alarm systems are improving every day, and the need for them is only growing. As prices for new models are rising. If we take an average security system and consider it as a contender for installation in a house, a summer house or a garage, then it will be incredibly difficult to fit into 20-30 thousand rubles. Meanwhile, it is possible to make an alarm system yourself from the old trash that everyone has in the house. It will be a fully functional intrusion alarm system or an addition to an already installed system.

What is a GSM alarm

To begin with, it is worth understanding the types of alarms and the principles of their operation. It is possible that we will choose among them the most optimal option for a particular object. For example, if it is necessary to protect a cottage on the outskirts of a holiday village from burglary, then the sound alarm itself will not help much here.

Putting a house under remote protection is effective, but expensive. But do-it-yourself GSM alarm from the phone will be the ideal option in this case.

Types of security systems

In principle, today the most common types of security systems are:

Sensors - eyes and ears of the security system

Each of these systems makes sense only when it can respond to penetration, violation of the integrity of doors, windows, walls, to the presence of movement in the protected area. And for this, sensors are needed, of which there are several. The most expensive and not the most reliable is an ultrasonic sensor. It fixes the intruder quite accurately and accurately, but only if there is no interference. And no one can guarantee this. In addition, such sensors are quite expensive and difficult to install and configure.

The magnetic sensor is the most popular, simple and reliable. It is a magnet placed on a door or a window, and a reed switch, which is in a closed state when in contact with the magnet. As soon as the magnet leaves the field of view of the reed switch, the reed switch opens, giving a signal to the warning system. There are also infrared motion sensors. If the integrity of the IR beam is violated, the system works. Such sensors have a high percentage of false inclusions, since they can respond to any movement or vibration. Sometimes you can find vibration sensors that react to the presence of vibration when trying to destroy a gate, door or wall.

The simplest door opening sensor can be generally a penny design - this is a group of contacts mounted on a door or on door hinges. When the doors are opened at least halfway, the contacts are closed, the GSM system is activated and the owner receives a call to the mobile phone. The most effective way, of course, is to install not one, but several sensors, connecting them using a special GSM controller shown in the photo below.

The principle of operation of GSM alarm

The principle of operation of a GSM system for a home or garage is simple and straightforward. Any mobile phone that has already served its purpose will be used as an active system. Our task is to make him call the owner when the sensor is triggered, but for this it is necessary that the balance on the card installed in the alarm phone is positive, and the phone itself is in the mobile operator's work area.

In order to assemble a GSM alarm system with your own hands, you will not need any special knowledge and a complex tool. Everyone who at least once in his life held a soldering iron in his hands can assemble such a system. Here is a list of the main tools and fixtures for assembling a signaling from a mobile phone:

old but working mobile phone;
reed switch and magnet, which will be a door opening sensor;
soldering iron and soldering kit - solder, rosin, flux;
ordinary household switch;
phone charger;
electrical tape, multimeter, wires.

How to assemble an alarm from a phone

First you need to make changes to the design of the old phone. Small, but they are needed. To start dialing the host number, as a rule, the standard green key is used. The desired number is entered and with each subsequent press of the call button, a call will be received not by the owner's phone. The button will work by closing the contacts. To do this, just remove the keyboard from the phone and solder two wires to the contacts of the call button, as shown in the photo.

In fact, the system is already operational. It remains to hide the door opening sensor, run a wire from it to the mobile phone, to those two contacts on the call button. The phone itself is installed in an inconspicuous place, it is also desirable to hide the wires, and connect the power supply, phone charger, to the network. The beauty of a simple system is that it will not lose performance even in the absence of current in the network - the battery of a mobile phone can last quite a long time without recharging.

Such a system has, of course, its drawbacks. The fact is that it takes several seconds to operate, that is, exactly the time that a mobile phone needs to make a call. This disadvantage cannot be called critical, therefore, in principle, the system is fully operational and can be used for home, for summer cottages, for garages, as the main or as an additional GSM system that duplicates an autonomous, already installed one.

We hope that the alarm, assembled by hand from a mobile phone, will not disturb the owners too often, and its undoubted advantage can be considered the price and absolute efficiency. Successful work!

If you have a dacha, a car garage or a country house, then sooner or later you will think about the means of protecting your property. The most popular means of protection in our time is the GSM alarm system. Now there are many types of GSM alarms from various companies. The only deterrent from buying a GSM alarm is its price. For example, the simplest GSM alarm Magnum МН-825-03 GSM 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, we have prepared a material in which we will describe the creation of a home-made GSM alarm system with our own hands. This signaling will be 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 residence or a country house

The first do-it-yourself alarm based on a mobile phone will be very simple. To assemble it, we need such Components:

old mobile phone;
reed switch;
standard battery charger;
long wire;
soldering iron;
solder;
magnet;
additional sim card.

Any old push-button telephone will do for this alarm. You can even use older models like the Nokia 3310. Principle such signaling 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 the number, configured in speed dial. Therefore, first of all, we will set up our phone for speed dialing, which will receive a call when the sensor is triggered. In our case, the speed dial button will be the ninth button. Also, turn off the ringer and vibrator on your phone. Another thing to consider is whether to use a charger for our phone or leave it to work on a fully charged battery.

Leaving the phone on a charged battery is only worth it if it can hold a charge for about a month.

Below is a diagram of the assembly of such an alarm for a summer residence or a house.

The figure shows how the Nokia 6150 phone is connected to reed switch. To connect the reed switch to the Nokia 6150, you need to disassemble the phone and carefully solder the wires to the pins of the nine button on the printed circuit board (Speed dial button). After that, the magnet and the reed switch are attached to the door. The scheme works like this: when the door is opened from the reed switch, a signal is sent to the button, as a result of which the phone dials the specified number in the speed dial. 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 an infrared motion sensor for a country house or cottage

The principle of operation of this GSM alarm system is based on infrared motion sensor, and not on the reed switch. AND infrared motion sensor is triggered when an object is in its field of view and sends a signal to a mobile phone. After the phone receives a signal, it dials the number previously configured in the speed dial. The scheme of an autonomous alarm on 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 should be noted that the motion sensor itself requires a separate 12 V power supply.

As the motion sensor itself, you can use the Astra 515 device.

This motion sensor has a range of 10 meters. For example, if any object gets into this radius of action, the alarm will work 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 system, assembled with your own hands, in the country house 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 is a situation when there is no old mobile phone at hand, but you want to save money on GSM alarms. In this case, it will help us Arduino board with built-in microcontroller. A distinctive feature of this board is its low price and functionality. In our example, we will use the board Arduino Uno, which costs about $ 4 (depending on modifications). We will use the GSM Home Alarm V1.0 article by Hugo Gomez as the basis for this example. 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 need such Components:

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

The cost of all components of such an autonomous alarm will be $35, which is still much cheaper than ready-made solutions. Principle the action of this alarm is based on the ultrasonic sensorHC-SR04, which captures the difference in distance and sends a signal to a mobile phone. For example, if a person gets into the measurement area of the sensor, then the sensor will fix the distance less than the set one and the Arduino Uno will send a signal to the mobile phone. The measurement 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 step is to install a SIM card in the GSM module.

You should also disable the PIN code on the SIM card in advance. Now we will connect the wires according to the diagram shown below, all the components.

The assembled GSM signaling will look like this.

In order for our GSM module GPRS Shield V2.0 earned in conjunction with the Arduino Uno, we need to download the library SIM900. You can download this library from this address http://www.gsmlib.org/download/GSM_GPRS_GPS_IDE100_v307_1.zip. After downloading, install this library. In the next step, we will need to open and edit the GSM.cpp file, which is located in a file in the SIM900 library folder. The fact is that the GSM module GPRS Shield V2.0 in conjunction with the Arduino Uno uses pins 7 and 8. So let's open the GSM.cpp file and change 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 in line 44, correct 8 by 9.

We figured out the module, now you can go directly to the code of our alarm. The code itself can be downloaded from this link https://create.arduino.cc/code_files/47730/download. In the 11th line of the code, you need to replace "XXXXXXX" with the phone number to which the signal will be sent. By uploading the code to the Arduino Uno, you can test the standalone GSM alarm. To do this, connect power to it and open the port monitor. The GSM module itself can register on the network for a long time, where you will see the message “Waiting for Network Registration”. If the network registration is successful, then the signaling can be tested. To do this, move your hand over the 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, the phone specified in the code should receive a call.

The example shows that a person who has already worked with Arduino Uno can easily assemble a similar GSM alarm 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, the price of which in Chinese online stores starts at 50 cents. Also, temperature sensors can be added to this warning system, which will notify the owner of the house, garage or cottage in case of fire.

Summing up

In this material, we have collected all the simple ways to assemble a GSM alarm system with our own hands. In addition to how to build a GSM alarm system with your own hands from an old phone, we described how to build an inexpensive system using an Arduino Uno board and a GSM module that acts as a replacement for a mobile phone. Also in the open spaces of the network you can find examples in which a push-button mobile phone acts instead of a GSM module. Such an alarm is similar to the examples described above, but thanks to the Arduino Uno, it has much higher functionality. We hope that 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.