How to make an alarm out of your phone. How to properly connect a mobile device to an alarm system? Sensors are the eyes and ears of the security system

If you find an error in the text, highlight it with the mouse and press Ctrl+Enter. Thank you.

Modern security systems for cars are, of course, reliable and quite effective, but additional protection in the form of a GSM alarm will never be superfluous.

A small device can promptly warn the owner of an attempt to break into a car or, for example, a garage where it is stored.

Principle of operation

Even the most simple GSM Do-it-yourself alarm system provides many advantages:

firstly, thanks to a mobile phone (the main element of the system), even in the event of theft, finding a car is significantly simplified;
secondly, when an attempt is made to break into the car (garage), a message is sent to the previously programmed phone number. All the owner needs is to respond to the danger signal in a timely and correct manner;
thirdly, the cost of all structural elements is minimal. Most often, you can meet the amount of up to 1-1.5 thousand rubles;
fourthly, with basic knowledge of electronics, assembling a circuit and testing the device takes no more than a few hours;
fifthly, the security system will work even in the absence of power - on the battery built into the phone. At the same time, time battery life can reach several days.

Depending on the complexity of the scheme and the skills of the car enthusiast, GSM alarm may have this functionality:

transmit messages about various malfunctions in the car;
automatically block the operation of the main components of the vehicle;
control the device in an unlimited range (the main thing is that there is a mobile network);
give various commands(for example, to start warming up the engine).

Best options

If a stand-alone GSM alarm system is what you need, then choose one of the options:

buy a ready-made device in a store;

In the first case, you get a "black box" with full set functions (all that remains is to connect).

In the second, you must do everything yourself. It would seem that the option of purchasing an already assembled alarm system looks more preferable, but there is a big disadvantage - the high price.

Therefore, if you have minimal skills in the field of electronics, a thousand to one and a half rubles in your pocket and some free time, then it is better to do everything yourself. Moreover, there is nothing complicated.

Option one

Component materials you will need: push-button telephone(you can use the cheapest one, but still workable with good battery), a magnet, wires, a reed switch and a simple switch.

The assembly process itself is quite simple and consists of several simple steps:

1. Set up a call to the required number (for example, your mobile) on one of the buttons.

2. Remove the front panel of the mobile phone. This is necessary to gain access to contact group devices and wire connections.

But there may be several options:

- the function of accepting and rejecting a call is on one key. In this case, one wire is soldered to it, and the second - to the number that you assigned to call the required subscriber;

- if the call and hang up functions are used various keys, then you need to solder its own wire to each of the three keys and use a three-pin reed switch.

By the way, the advantage of this installation is that the phone will turn off along with the alarm, which can significantly save battery capacity.

3. Last step– installing a magnet on a door (garage or car), as well as setting up its operation.

The further principle is very simple: when the door is opened, the reed switch contacts open, and the car owner receives an alarm message about an intruder breaking into the car (garage).

A switch must be provided in the reed switch circuit, with the help of which the GSM alarm will be turned on or off by the owner. In this case, you can choose the location of such a switch yourself. The main thing is that the toggle switch does not catch the eye of intruders.

The advantage of such a self-assembled system is absolute autonomy. The main thing that needs to be considered is the issue of constantly recharging the battery.

Ideal option if Charger will be able to connect to on-board network car (in the case of installing protection in a garage - to a 220 V network via an adapter).

In this case, the phone will be constantly recharged over a long period of time.

The disadvantage of such a system is a slight delay in operation, because it should take some time to call a subscriber.

If suddenly the attackers quickly entered the garage (got into the car) and closed the door, then the circuit will be open and the signal may not reach.

But this problem can be easily solved - it is enough to equip the magnets with a special product that will prevent the circuit from opening again.

There are many options here to solve the problem. For example, one of the simplest is to install a magnet in such a way that when quick opening the door was moving.

In this case, after closing the door, the circuit will not open immediately and the GSM alarm will do its job completely.

Option 2

Here the circuit is a little more complicated, but the functionality is much richer than in the previous case.

Such a device is triggered when at least one input is short-circuited to the negative of the vehicle. Moreover, the alarm system itself has four security inputs: for the driver’s door, for all passenger doors, for the luggage compartment and, accordingly, the hood.

After turning on the power switch, you must quickly get out of the car (no more than 25 seconds). If suddenly the driver does not have time, the control LED will not light up until all the doors, hood and luggage compartment are closed. As soon as the conditions are met, the alarm will go into security mode.

When an attempt is made to steal and one of the doors is opened, the headlights turn on, and, if desired, the turn signals.

To turn off the alarm and remove all locks, just turn off the toggle switch hidden in a special place.

In the case where the attacker immediately closed the doors after the alarm went off, the blocking is not removed. At the same time, the car owner still receives an alarm call.

After 40 seconds, the control unit will poll all systems and, if there are no triggered sensors, will go into standard security mode. If, during the test, the opening of one of the doors is confirmed, the device goes into alarm mode.

As in the previous case, to implement such a scheme, you need to buy a mobile phone with the ability to quickly dial. In this case, the call will be made until the subscriber at the other end of the “wire” presses the reset button.

You can use an ATMEL product as a controller, although there are many analogues. Its advantage is its affordable price and reliability. In addition, such a controller can be easily found on the market in your city.

Any 12 V devices can be used as a relay. The toggle switch for turning the alarm on and off is also not difficult to find. In this case, it is advisable to hide it away from prying eyes. The more reliable the place, the better.

The toggle switch is inserted into the alarm power supply circuit from the on-board network.

Installation rules

When installing such a device, you need to consider a few simple recommendations:

Firstly, before starting work, study the gsm alarm diagram and strictly follow all the recommendations. If you bought a ready-made device in a store, work only according to the instructions;
secondly, to install and connect the device, it may be necessary to remove the instrument panel and dismantle the protective panels under the steering wheel;
thirdly, turn off the power (to do this, just remove the terminals from the battery);
fourthly, install the control unit (mobile phone) in close proximity to the fuses (this will greatly simplify the connection);
fifthly, install alarms and other sensors (if they are provided for in your circuit);
sixth, carefully lay out the wires so that they do not interfere with the process of driving the car;
seventh, connect the device to the on-board network.

Connection secrets

From the moment of installation, the GSM alarm system stands guard over your car, so every little detail matters. Moreover, there are a number of connection secrets that you need to know about during installation:

The main task is to provide independent power to the device, which can be turned off and on using a hidden toggle switch (we have already talked about this).
All wires must be laid in places where moisture never penetrates. This is necessary to avoid possible short circuit and system failure.
Try to mount the main unit, sensors (if any) and wires as far as possible from heating and vibrating elements of the car. Otherwise, there is a high probability of system damage and failure.
The device control unit must be removed from the phone, car antenna and radio to avoid interference.
The places where the wires pass from the body to the doors or from the body to the hood must be additionally reinforced with special rubberized tubes to avoid creases and damage.

Installing such an alarm system is a responsible process, so there is no need to rush here. Each connector must be cleaned with special care and carefully insulated to prevent dirt and dust from getting on it.

conclusions

Thus, a GSM alarm system can become your reliable assistant in ensuring the safety of your own car.

All that remains is to decide on your priorities - make the device yourself (by choosing one of the options) or buy it already ready-made system. But here a lot depends on the tasks assigned.

If your car already has an alarm system and you need an additional device, then why not do it yourself.

If the security system is on GSM principle will be the only one, then it is better to install more functional protection or buy a ready-made device. In any case, it's up to you.

If there is a video in the article and it does not play, select any word with the mouse, press Ctrl+Enter, enter any word in the window that appears and click "SEND". Thank you.

The other day an old friend contacted us. He lives in a private house and a couple of times unknown persons tried to visit him without an invitation. There is a need to install an alarm system. It turned out to be too expensive to put the house on the remote control. It seemed like the optimal solution was to simply notify the owner with a call to his mobile phone when one of the motion sensors was triggered.

First, we visited local stores that sell burglar alarms. However, the prices for the most budget GSM devices have been high - from 5 kilo rubles per unit. Therefore, we decided to build a GSM alarm system with our own hands.

We had a Nokia 1600 mobile phone with the screen backlight turned off (a chronic problem with this model after swimming) and a 12-volt power supply. We had to purchase only the most inexpensive Astra volumetric detectors (200 rubles each), a 12-volt battery with a capacity of 7.2 Ah (another 400 rubles), several meters of four-core installation wire (~50 rubles) and a cyclic daily timer (250 rubles).

We have chosen the following alarm operating logic. When at least one of the volumetric volumes is activated, the call button (green tube on the device) begins to be “pressed”. On Nokia phones The first press brings up the last dialed number on the screen, the second makes a call to this number. Subsequent presses do not affect the operation of the phone.

To implement the intended algorithm, we collected simple circuit on domestic logic.

This simple generator impulses. With the indicated ratings of R1 and C1, the pulse frequency is approximately 1 Hz. The generator load is an optocoupler. We pulled him out computer unit nutrition. Right part the optocoupler is connected to the contacts of the call button mobile phone. To do this, the phone is opened, the button contactor is removed, and thin wires are soldered to the contacts.

A tact button is included parallel to the wires. It is needed to configure the system.

The volumetric volumes we have selected in a normal state (no alarm) have a relay output with a normal closed contacts, which break the circuit when the device operates. We used this to control the click generator.

The volumetric output is switched on parallel to the optocoupler and, in security mode, simply short-circuits the generator output to ground. The current limiting resistor becomes the only load on the generator. When the circuit is opened, the current flows through the optocoupler and the system begins to work.

Now about setting up your mobile phone. Automatic keyboard lock must be turned off. Clear the log of all calls, set all call forwarding voice calls to the MCA number - Missing Call Alerting ("You have been called" service). This is important, otherwise it is possible that the system will answer a random incoming call instead of calling the owner’s phone. Then you need to dial the owner’s number and press the remote call button. If everything is assembled correctly, the owner's phone will ring.

Our volumetric units support only one operating logic: after triggering, the alarm loop opens for one minute. During the same time, the phone will try to reach the owner. It is impossible to get rid of him.

The relay outputs of several volumetric tanks should be included in the alarm loop in series. Then, when any of them is triggered, there will be an alarm in the circuit. The number of volumetric volumes connected in this way is limited only by the resistance of the wire.

The generator and volumetric units receive energy from a 12-volt power supply. The phone runs on its own battery, only once a day the timer is turned on (for an hour and a half, selected experimentally), which recharges the phone through a standard charger.
Arming and disarming of the device is carried out by a disguised switch inside the controlled room. Thus, the “arrangement through alarm” mode is performed. This is convenient; the functionality of the system is checked every time before turning it on.

An extended version of this alarm system has a battery backup. In our case, the 12-volt battery is connected in parallel with the main power supply. The power supply is turned on via a diode. It prevents the battery from being discharged through the power supply when it is de-energized.

Thus, if you have an old phone and direct hands, you can get a suitable GSM detector that costs less than a thousand rubles. Our system works for a friend without any complaints, false alarms does not give. For convenience, he even put separate ringtone in the form of a siren for incoming call from the system.

Installing an alarm in your garage is a very smart decision. At the same time, it is not necessary to buy something expensive and sophisticated. The simplest GSM alarm system you can mount and with your own hands.

All you need for this, besides a soldering iron and basic knowledge of electronics, is:

old unnecessary mobile phone (necessarily push-button);
magnet;
hermecon (sealed contact, regular or with three contacts, depending on which connection scheme you use);
wires and a regular one-key switch.

Theoretically, limit switches can be used instead of hermecon, but in a humid environment they are not very reliable. Why make an alarm system that you can’t rely on?

The installation of the GSM alarm system itself takes place in several steps:

The principle of operation of such an alarm is very simple: when the gate opens, the reed switch closes the contacts and the phone rings your number.

In order to put the alarm in the “combat” position and, conversely, turn it off, an additional switch is provided in the circuit. Where exactly to place the telephone, switch and other structural elements depends on the structure of the garage. The main requirement is that these places be protected from moisture and from prying eyes. Actually, the more inconspicuous the installed system, the better.

An undoubted advantage of such an alarm system is its independence from the electrical network. You just need to charge your mobile phone battery in time, using standard adapter. If you have electricity in your garage, then it is advisable to install this adapter into the network, as shown in the diagrams above, so that the phone runs directly from the battery only during power outages.

Finally, we need to provide one more important nuance. This GSM alarm needs a certain amount of time to trigger– a few seconds while a connection to your number is established. Therefore, if intruders quickly close the doors immediately after breaking in, the circuit will open again and the call will be reset.

Do you know how it is produced? This article will help you avoid major mistakes when installing an alarm system.

Video surveillance is also good for home protection. And video surveillance kits, which you can find out about at, will help you save time and money when purchasing equipment.

If you want to independently choose video surveillance equipment and install it, we recommend that you read the article located at

To prevent this from happening, you need to equip the magnet on the moving part of the gate with some kind of additional device, which will not allow him to open the circuit again. There are a lot of options here, it all depends on specific device gate and from your ingenuity.

The simplest option is to make the magnet move slightly from its place when the gate is opened. Then, if the gate is closed, the magnet will not come into contact with the reed switch and will not open the circuit. To bring the system into the initial state, you will only need to move the magnet to its original place.

Modern society is simply unthinkable without security alarms. A security alarm can be either a fire alarm or a regular one that works against intruders. It all depends on where it is installed and what functionality it should carry. Do-it-yourself GSM alarm system - relatively inexpensive and sufficient effective solution for protecting a garage or home.

Now there are a large number of companies ready to install alarm systems, including GSM. Scheme similar systems not as complicated as it might seem at first glance. The main thing is to understand some of the nuances and it is quite possible not to resort to help third parties, but make an alarm with your own hands. It will cost much less, and it constant maintenance will depend only on you. That is, you can repair it and carry out service yourself.

If you want to do it right, do it yourself

The most widespread use of such alarms is in the garage. The simplest homemade GSM An alarm system will help solve a number of problems and add confidence in the safety of your car.

What do you need to have to make an alarm yourself?

If you look closely at the above list, you can come to the conclusion that the cost future system not tall. A DIY security alarm like this will last a long time if you follow all the following steps correctly.

Installation work

A good GSM alarm with your own hands will work for a long time and correctly if you follow the following steps step by step:

In cases where shutdown and hangup coincide, you need to solder a wire to this button. The second wire is soldered to number key, which corresponds to the function quick call. This is where your phone number is dialed. As for the hermecon, you need to use one that has a standard circuit.
In cases where the shutdown and hang up do not coincide, it is necessary to solder another wire to another button. In this case, one of the wires will be common. As for the hermecon, the one with three contacts is used.

Proceed with the installation of the closed circuit, working with the diagram. It is necessary to install a magnet on the garage door, and then adjust the reed switch so that contact with it means an open circuit.

The resulting security alarm works quite simply. If the garage door begins to open, the contacts are closed using a reed switch. As a result, a call comes to your phone. This serves as a wake-up call.

It is important to note that before starting installation, you should consider how to do the work so that the security alarm is least noticeable to prying eyes. In addition, all elements must be protected from moisture.

The list required for installing an alarm system includes a switch. It just serves to turn the system on or off. Everything is very simple and functional.

You will immediately be able to appreciate the main advantage of installing such an alarm system. The fact is that it does not depend on the electricity network. You will only need to timely charge the mobile phone used in the system. There are batteries that can hold a charge for more than two weeks. By the way, similar mobile phones with batteries cost from 890 rubles and more.

In garages that have an electrical network, the adapter can be mounted directly into the network. Then you will need to ensure that there are no power outages.

A nuance that is important to know

If thieves get inside your garage, which is equipped with an alarm, they can quickly find it and turn it off. At the same time, the alarm has certain time for it to work. This lasts literally a couple of seconds. In it time is running

the process of establishing a connection with your mobile phone number.

When the door is quickly closed, the call is immediately dropped. In order to prevent this, you can install another device to the magnet. It will have to prevent the magnet from opening the circuit.

Currently, it is also recommended to install a video surveillance system. But these are additional expenses. In most cases, it is enough to have a DIY GSM alarm system, which will help you find out in time that a stranger has entered the garage.

A distinctive feature of wireless alarm systems is that the tracking sensors communicate with the central unit via GSM network. To operate, a SIM card of the selected operator is installed into it. GSM equipment is a home alarm with telephone notification. After switching on, the central unit finds all installed sensors and begins taking readings. If one of the sensors is triggered by movement or another indicator of a violation, an alarm is sent to the center and a siren sounds, and a message is sent to the owner’s mobile phone.

The device is programmed so that the phone beeps until it receives a signal. The mode of the central unit is set by the owner, each zone is programmed to specific signal, and when it arrives, it becomes clear in which sector the tracking sensor is triggered. The equipment is installed in various fields production, used in offices, private buildings, GSM installed

Benefits of a wireless tracking system

The device has many advantages over conventional alarms:

wireless system works easily in homes and separately standing rooms, in which there is no telephone or electricity;
not paid subscription fee for a quick response and the arrival of a security detail, the signal instantly notifies the owner, and he acts at his own discretion;
The system design provides protection against false responses to the movement of insects and animals, which is very valuable compared to conventional equipment.

Components

The device is available in a standard or extended version. Standard scheme equipped like this:

tracking sensor;
alarm sensor for opening a door or window;
siren device;
set of key rings.

The standard equipment is expanded by additional number sensors, and additional notification devices are added gradually after installation of the main equipment.

Review of the model "Guardian Falcon Prof"

Set of devices High Quality used in wireless "Guardian". GSM home alarm is a representative of a new generation of systems to which sensors can be easily connected various types. It is possible to install a microphone to listen to the protected area. Alarm messages and dialing are sent to three telephone numbers. For notification, the central point contacts 9 wireless notification zones, round-the-clock operation is provided for

SMS messages in Russian are transmitted by a home alarm system with notification by telephone. "Guardian" is characterized by a battery large capacity, allowing you not to recharge the system for up to three days. Programming the system is done from the remote control or by telephone message, which saves telephone costs. If the signal level at the central point loses intensity, then the owner’s phone receives a message about the use of a cellular wave suppression system in case of a hacking attempt.

To determine the operating mode, a wired free-standing beacon is used, which notifies random visitors about the security of the premises or object. If there are places in the territory where the radio signal is blocked by various reasons, then connection is provided wired devices To general center. The specified GSM alarm system for the home works as a reliable and functional system.

Alarm Falcon Eyei-Touch

The equipment belongs to standard wireless devices. Sold with installed program, expansion of the field of activity is provided through the installation of additional reading sensors. Wireless GSM alarm system for home and garden differs in that up to 50 sensors and about a dozen remote controls are connected to it remote control, which are easy to manage. For an alarm message there are 5 telephone numbers, from which the operation of the device can be easily reprogrammed. A notification to the owner comes when the batteries are low, the capacity of which allows them to work autonomously for 5 hours.

Falcon Eye Simple security system

The model is intended for installation in residential buildings. The successful design look easily fits into the most sophisticated interiors. Standard set components of the devices are the same as in the "Guardian" system. GSM alarm systems for the home are also expandable if there is a need to increase the surveillance area. Work with a large number information readers, has a voice message, listening to the controlled area. The communicator is easy to maintain and control, programming is carried out telephone message. The battery lasts about 8-9 hours.

Signal XM - reliable security

The text in the message is sent to English language, which is not always convenient. If the ambient temperature drops to -5ºС, then the capacity of the batteries in the sensors may decrease. It has affordable price with good functional ability. A type of alarm system used for installation in a garage is called Signal XQ. This device has several types of sensors that respond to vibration, smoke, and movement. It is possible to receive a message once a day by phone or every time upon request.

Alarm System SGA-G10A Android

Ideal for indoor installations for various purposes. Wireless GSM alarm system for home is a ready-made kit for use in a garage, apartment, house, or office. All devices are adjusted, and the kit is easily installed by a person without preliminary preparation, That is in a great way saving money on inviting a specialist.

The alarm box has a successful design solution, allows its installation in various styles of room decoration. Touch elements are provided for control, technical specifications systems are displayed for viewing on the screen. The work is simplified to pressing one button, increasing the number of sensors is much easier than in other systems. For today it is best GSM alarm system for home. User reviews are positive.

It is allowed to connect up to a hundred wireless surveillance zones and two wired ones to the central unit, the number of numbers for voice notification is 5 pieces, SMS messages are 3 pieces. The intruder is detected at a distance of up to 12 meters, the increased viewing angle of the zone is 110º. The alarm operates with sensors at a frequency of 433 MHz. Sensors are used various types: opening the doorway, movement, breaking glass, vibration.

The activation of the siren can be heard at a distance of several hundred meters; if there are many objects, then you can see which one is in danger on the screen (mini-display), and the response time is also displayed there. The system operates in two standards telephone communication, works with all operators, connects, at the owner’s request, to a landline telephone.

It is possible to program commands from the phone; now there is no need to remember complex digital and alphabetic codes, operations are carried out by pressing one button. The name of the security zones from the number is renamed according to the name of the premises, for example, kitchen, bedroom, etc.

Security alarm kit 30 A

Appeared on the market recently and has already collected a lot positive feedback, thanks to excellent quality at a relatively low price. The device consists of plastic case with an opening lid, the keyboard is backlit. Built in with a well designed interface. Modern device newest generation becomes not only an assistant to the owner against encroachment on the territory, but also speaks of the luxury of home ownership.

The call is made from voice message to 6 phone numbers. A home alarm with telephone alert sends a message to three numbers if the sensor is triggered. Up to one hundred information collectors are connected to the system, which are placed on all possible variations of penetration, for example, a door, a window, a safe, or collapsible enclosing structures. The system settings are displayed on the screen, working condition alarm system, the alarm unit is used as a telephone for calling friends and acquaintances.

Selection criteria and price

Having considered the features and specifications all systems, choose the optimal parameters for installation in the selected room or open area. For large areas, systems with connectivity are used large number sensors, but such kits are more expensive. Small economical premises, garages are protected by small functional systems to reduce the cost by not large quantity sensors

Price is often a determining factor in purchasing equipment, but for wireless alarms it is one of the advantages. On average, the cost of a standard set is about 7-11 thousand rubles, which makes it affordable for the general public. This is a low price to pay for peace of mind for your property, with the condition of prompt notification in connection with violations.

A home alarm with telephone notification is selected taking into account the name of the manufacturer and the country of production. Chinese lightweight models are equipped with a case made of low-quality plastic, batteries are often not included in the package, and sometimes there is no warranty for the equipment. Such systems are cheap, but the quality leaves much to be desired.

Security equipment is selected taking into account functionality, the best set serves as a GSM alarm system for the home, it instantly transmits a signal to the owner’s phone and allows him to react very effectively. If the system is equipped with a siren, then strangers will not want to be in the apartment even after a successful break-in.

When choosing, take into account the possibility of connecting wired systems, battery capacity, availability convenient screen With clear interface. Based on this data, choose optimal solution to protect the facility. Important components of the kit are additional functions, such as temperature control, network voltage.

Connection instructions

GSM home security alarms are easy to install and will not take much time even for an untrained user:

selecting a location for installing the central control unit;
tracking sensors are mounted in the places of their monitoring purpose, preferably on equal distance from the central block;
infrared sensors are placed on the line of possible human passage, at a height of no less than 2 m from the floor surface, the angle of inclination is no more than a right angle;
sensor motion detection range is about 8 meters, inspection angle is no more than 110º;
opening sensors are installed on a fixed frame, a magnet is placed on a movable sash, a gap between them is maintained of no more than 1 cm;

Making an alarm with your own hands

Craftsmen create wireless alerts in the event of dangerous situations on their phones themselves, which helps save money. For work, purchase materials and tools:

mobile phone with the ability to quickly dial the selected number;
sensor for reading sounds from the surrounding space in the form of a microphone;
push-button sensor for opening an opening (window or door);
12V acid-gel battery (you can take a battery with a larger capacity, which will increase the time offline use in the absence of electricity);
Accumulator charging;
soldering iron, solder, pieces of wire.

A home alarm with telephone notification works on the principle of closing a contact on the cell of one of the numbers in the phone for which it is programmed speed dial owner numbers.

Procedure

A number is selected on the keyboard, and the ability to quickly dial is configured in the phone functions. To avoid surprises in the future, speed dialing is checked when a key is pressed. After this, the back surface of the mobile phone is removed, then the front part with the screen is removed, and the board, protected by a white film, is released for work.

To connect the wiring, two cuts are made under the desired button. After lifting the film, a metal membrane located with inside. This part performs the function of closing two contacts, the midpoint and the ground. The wire is soldered to two contacts; it is advisable to take one so that there are two wires in the winding, this will reduce the number of interference and false calls.

To prevent unexpected short circuits, a small square of insulating tape is glued to the membrane, closing it. If it is planned to eventually return the phone to normal working use, then the membrane is not removed. The cell phone is prepared for operation, and then a home alarm system is installed with telephone notification. It’s not difficult to make such a connection with your own hands; you decide on the option of closing two contacts.

Two microcircuits are used: K561LN2 and K561LA7, this alarm sets the time for the owner to leave the boundaries of the protected object and determines the period for the owner to enter the territory to turn off the alarm. At this time, there is a delay in response to movement and other parameters. A self-designed wireless GSM home alarm system expands its application possibilities by installing additional sensors.

Options for connecting a phone to an alarm system

For one of them, a relay with open contacts is used. The relay coil is connected to the alarm output. If an alarm is triggered, voltage is applied to the winding, the contacts are connected, and the phone button is pressed, sending a call signal to the owner’s phone.

The second method is to connect a bipolar transistor directly to the phone keypad. The output of the transistor is in contact with the common wire, and its collector is connected to the push-button contact. Voltage is supplied to the transistor base through a resistor and the GSM home alarm system starts working. Reviews from those who use this scheme indicate its sufficient reliability.

Connecting a telephone using an optocoupler helps create an isolated circuit from a galvanic point of view. An optotron is an electronics device containing a light emitter and a photodetector, enclosed in a common single housing. Both components of the optocoupler do not have common contacts, so security circuits are powered from different sources without common wires.

All three connection methods are valid when connected cell phone to any alarm. A GSM alarm system can be installed for a home or garage and can be easily connected to car security.

How to ensure uninterrupted power supply

Apply charging phone battery an ordinary device. This is a simple method, but the battery is constantly in fully charged, And lithium battery is gradually destroyed.

An ordinary phone battery is used, but for charging a fixed power source voltage of up to 4 volts is used with a permissible load current of 700 to 1000 mA. This power supply allows you to accumulate not the full volume in the battery, but only up to 70-75%.

Another option is to bypass the landline telephone battery and connect to a battery security system, which is up to 12 volts and is constantly recharging. In this case, a current converter or transformer is installed. Before connecting such a device to the phone, be sure to check the output voltage, which should not exceed 3.9-4.0 volts.

A sagacious owner must protect his home, work enterprise, garage, or car from attempted break-in and entry. Wireless alarms help to perform this function reliably, economically, without difficulties and problems.