Do-it-yourself car alarm from a cell phone. GSM Alarm from an old mobile phone. The nuances of connecting a mobile device to an alarm system

M a rich application that turns a smartphone into an “electronic watchman” - the idea, in general, lies on the surface! As you know, in a good modern alarm system, in addition to the traditional reaction to body vibrations, breaking glass, opening doors, turning on the ignition, etc., it is possible to control it via a mobile communications channel and communicate with the owner via phone calls and SMS. And besides, do various useful things using GPS: report the coordinates of a parked car, when a car leaves the boundaries of a pre-designated area, draw a route track...

Actually, most smartphones could do the same thing if they were controlled by an application with an operating algorithm close to the operating algorithm of a car alarm. There are many such applications, and although some of them are designed to counter the theft of the phone itself, some are also designed to protect the car. It's easy to find them in the Google Play app store. And outdated devices that have long been “decommissioned” are suitable for these tasks.

“Alarm” applications

Let's install and test a couple of programs to understand their essence and capabilities. The application, simply called “Signalka,” is free and has a fairly simple and logical interface, which is good news. It also has two operating modes.

1. First mode of operation. In it, the application makes an “alarm” from the smartphone, calling and sending SMS to a pre-populated number in the event of a motion sensor being triggered, the car leaving a certain zone, etc. Accordingly, the second phone, to which alarm messages will be sent, does not need such an application and can even be a regular push-button phone. But then you will have to turn the alarm on/off manually, which is difficult to do if the smartphone is deeply hidden in the car.
2. Second mode of operation. In this case, you will need two smartphones - both have the Signalka application installed, after which one hides in the car interior and serves as a watchman, and the second smartphone, which the owner always has with him, uses the same application as a remote control for the first one via Bluetooth . This is the most convenient mode, allowing you not to touch the gadget hidden in the cabin unnecessarily - if, of course, it is constantly connected to the power supply.

In the application settings, you can adjust the sensitivity of the vibration sensor, the radius of the tracking zone, the exit of the car beyond which will trigger an alarm (from 20 to 120 meters), as well as the events for which SMS will be received - the activation of a motion sensor, turning on/off, low battery and etc. There is also a tracker mode, in which after the car leaves the tracking zone, the device will start sending you coordinates every 5 minutes.

The author of another application, under another “original” name “Security Alarm,” designed its interface, frankly, unsuccessfully. Not everything in it is intuitive, there are a lot of abstruse problems that burden the average user, such as a running graph of vibrations of the smartphone body.

There is no intuitiveness - you need instructions for use. There are instructions, but among the on-screen sections (“Main”, “Calibrations”, “Settings”, “Other”) it is not visible - it is found only if you click on the three dots in the upper right corner of the screen, where an additional mini-menu is hidden. Moreover, the application is also paid...

One way or another, it is curious that the developer in the program focused on the fullest use of the smartphone’s motion sensor – the accelerometer. The user can not only adjust its sensitivity according to the “more/less” principle, as in the previous program, but adjusts it in numerical values ​​independently along each of the three coordinate axes X, Y and Z. In the application settings, the user can set the angles, the achievement of which will lead to to trigger an alarm and send an alarm SMS. And in the same SMS you will receive digital data about changes in nodes along the coordinate axes.

If the position of the smartphone is known, it will probably even be possible to draw conclusions about what is happening with the car, recognizing jacking, subsidence on an ice crunch under the wheel, or loading onto a tow truck. Whether it is convenient and how necessary it is is an open question, but in any case, this solution is unusual, distinguishing the application from others.

This is what messages that come from a smartphone as an alarm look like:

Benefit or pampering?

An unpleasant feature of a telephone-based “alarm” is that it absolutely does not have any protective functions. It will be able to notify the owner of the alarm, but it will not be able to prevent thieves from starting the car if there are no other protective electronic or mechanical means on the car.

Accordingly, the question arises:

In what situations might a budget alarm system from an old cell phone make sense? Actually, there are two options here.

1. If the car already has a good security system consisting of an alarm system, an immobilizer and a hood lock, but the security system has weak service functions - a short-range key fob, no GSM and GPS. In this case, an old smartphone will be able to increase the usability of the existing security system - make the control range unlimited, report the coordinates of the car, remotely listen to the situation in the cabin, etc.
2. An even more budget-friendly option is to combine a smartphone with homemade simple locks, which can be done by many who have even minor electrical and radio engineering skills. A couple of tricky and unexpected locks based on hidden buttons, standard key combinations, etc. can sometimes turn out to be no worse than an advanced “signaling”. And the smartphone, again, will add remote communication with the car to homemade products.

Installation and power supply of a smartphone

Finally, an important digression. The descriptions of “alarm” applications do not say anything about the power supply of the smartphone, and not everyone will immediately think about it. However, powering a smartphone, if you suddenly decide to use it as an “alarm”, is a special issue.

With GPS and GSM turned on, as well as with the G-sensor constantly active and waiting for vibrations of the car body, the device will be discharged in a maximum of half a day. And if we use a “retired” old man or a new, but ultra-budget gadget, the battery of which is far from the records of capacity and quality, it’s good if the battery lasts for several hours...

This means that you will have to provide constant power to the phone. This is not a difficult task, but it requires some fiddling. First, you need to find a place for your smartphone in the car interior that is both invisible during a superficial inspection and relatively accessible so that you can perform some actions with the touch screen if necessary. Well, so that the GPS works. These are, to put it mildly, mutually exclusive things, but we hope you can handle it.

After this, you will have to connect the power wire to the place where the smartphone will be hidden from a point where 12 volts are constantly present (regardless of the position of the ignition key). And then, in the immediate vicinity of the smartphone, you need to turn these 12 volts into 5 volts - using a car charger with a microUSB plug on the cord.

It should be noted that constantly connecting the phone to charging is an acceptable, but not the most optimal solution... Yes, after the charging is complete, the battery controller goes into a seemingly safe standby compensation mode, but...

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, the simplest GSM alarm Magnum MH-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 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 battery charger;
• long wire;
• soldering iron;
• solder;
• magnet;
• additional SIM card.

Any old push-button telephone will be suitable for this alarm. 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 a diagram of connecting a Nokia 6150 phone 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 contacts of button nine on the 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 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 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. 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). 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 than 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 fact is that the GSM module GPRS 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 must replace “XXXXXXX” with the 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 can take a long time to register in 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 all the simple ways to assemble a GSM alarm with your own hands. 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 instead of a GSM module there is a push-button mobile phone. 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

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 an information system that rings, for example, when someone opens 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.

Good evening, dear friends! Another weekend has arrived, which means you can relax or make something out of a pile of used household appliances. I’m sitting on the social network VKontakte, scrolling through the page, but my thoughts are completely different, I’m thinking about what useful things can be made. And then suddenly my gaze fell on my cell phone. I remembered that I had an old cell phone lying around in my bins that worked, but the model was outdated and there was no longer a need for it. Without thinking for a long time, I came up with an idea to make an alarm out of it via a GSM channel. So let's get started.

First you need to find an old cell phone that you don’t mind taking apart and “spoiling” a little. I personally had the Siemens S65 model on hand. The old, good, reliable model was, in principle, and remains so now :-) Your phone should have a speed dialing function (well, when, for example, you press key 2, your saved subscriber under this key is called).

I disassembled it without any problems, since I had a set of these screwdrivers for a long time. We will need a green keyboard board.

This is what it looks like from the side where the buttons are pressed. We find key 2 (personally, you can use any of the numbers) and remove the round metal plate on it.

When the metal plate is removed, your result should look like mine. These are the contacts that closed when key number 2 was pressed.

Now we take a soldering iron and carefully solder two wires there, one wire to the central point, and a second wire to the ring. Take a thin wire, otherwise the case will not close later. Now we put everything back in place, all parts of the phone should be where they were before disassembling the phone.

That's it, we have the phone assembled, but two wires are sticking out, we clean them out. Now we take an additional SIM card and install it in this phone. I want to say that if the SIM card is new, it will be even better, since no one will call this number and unnecessary messages will not come either (in particular, any advertisements from short numbers). After this, we save your personal number under key 2 as a speed dial, and in your personal phone the number of this SIM card that you inserted into this modernized telephone with wiring, for example, under the name “Car Security”. On the same phone, you can turn off the screen backlight, be sure to turn off vibration and ringing. That's it, now you close the two wires and wait for a call to come to your phone from the alarm system of this phone. Thus, you can listen to what is happening where this upgraded phone is installed, for example, the conversation of robbers. I have a reed switch at the end of the wires (this is a glass tube, there are contacts inside it, the contacts are activated when a magnet is brought to it). They are available in radio stores, but instead of them, you can install a regular microswitch with open contacts. Their number is not limited; you can install as many switches as there are protected doors, for example in a car or in a country house.
Well, I forgot to say, if the phone is very old, then always leave it on charge, this will give you more guarantee that the battery will not run out. Well, that’s all I wanted to tell you today. This article will be improved and become more complex, so to begin with, I started with something simple, so that even those who have never picked up a soldering iron, much less disassembled household appliances, could assemble it. Collect, try, experiment, and share what you get out of it :-) See you again, Dear friends! Thank you for your attention!
P.S. I even made a short video of how it works.

We are talking about the use of a security alarm installation scheme in which, in the 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 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 device is better than no security at all. In addition, for some applications (garage security, for example), this degree of security may be quite sufficient.