Simple do-it-yourself alarms. Homemade alarm for a car How to make a homemade alarm with improvised means

The protection of private property has always been an urgent problem. Nowadays, there are many ways to protect your valuables or home: you can hire a security guard, set an alarm, insure, etc., etc. But what to do if these methods are too expensive in relation to the protected property, but you still don't want to leave unattended, for example, a summer residence. The author will tell you how he found a way out of this situation by making an autonomous burglar alarm with his own hands!

What we need to create an alarm:
1) Passive IR motion sensor (required for the system to react to an intrusion)
The author bought a light switch for 300 rubles.
2) Siren 12 volts (needed for intrusion alert)
In this case, a power of 105dB was used, but as you understand it depends only on your desire. The cost is about 200 rubles.
3) Battery holder
4) 6 V relay,
5) insulating tubes,
6) wires.
7) the batteries themselves.

So let's analyze what we need from the signaling itself.

The work of the notification should be for a short time and turn off itself after a certain period of time, and then again work in the standard standby mode. The system must be able to fire multiple times. Low voltage current, for long-term operation (at least half a year).

Let's start with reworking the motion sensor, you need to transfer it from 220V to 12V.

After analyzing the circuit, it becomes clear that it is capable of working even when powered from 8 V to 30 V. Actually, with the required 12V power supply, we must set the relay to 6V. We proceed to disassemble the sensor. The spherical part can be removed if one of the supports is bent. The element is fastened with latches.

After removing the board, it is observed that the sensor is nothing more than a passive IR receiver, the reaction of which is associated with a change in the power of IR radiation incident on it and a simple optics system. Sensor viewing angle 180 degrees.

Next, you need to power the points that are on the left. Negative and positive charges according to the charges of the power source (plus +, minus -).

The points on the right are needed to connect the relay coil. And the standard relay installed on the sensor (it looks like a black box) must be removed.

Since there is not enough space inside the spherical shell of the sensor, it was decided to lead the relay into the base of the housing through wires.

The actual power is supplied to the sensor through the switch, and when the system is triggered, power is also supplied to the relay. Which in turn leads to the inclusion of a siren, notifying us of the penetration.

By the way, the number of possible connected sirens is not limited.

As you can see, I will lower that the siren, that the batteries are connected to the system through the terminals. Above and to the right is the switch, and the relay itself is located at the bottom left.

And so we put together our security system!

ATTENTION! Protect your ears before checking the siren! Otherwise, you can damage your hearing, which is naturally undesirable. And do not be confused by the small size of the siren, it is really very loud.

What did we get. Thanks to the regulator, it is possible to set the time on the sensor that the siren will work after identifying the entry into the protected area. The author got from 10 seconds to 8 minutes.

The sensor is installed indoors (for example, at the door), and the siren is output to the street.

It is important to know that after turning on the power, the siren goes off, so the author suggests placing the switch in a place invisible to the eyes.
For the sensor to work for 6 months, 16 mixed alkaline batteries are enough.

Also, the system has been successfully tested in the freezer, which will make it possible to assert its excellent performance even in winter. at -30 degrees.

After the author installed the system in the country, he revealed:
1. Glare from water, unfortunately, can cause a false alarm.
2. If the sensor gets swept away, malefactors can seal it with iso-tape, thereby creating blind spots.

This article provides diagrams of the simplest electronic alarms that can be made by anyone who is at least minimally familiar with electronics or just knows how to hold a soldering iron in his hand. Such alarms will come in handy in many cases. They can be placed on the windows if there is a small child in the house who can open them. There is a guarded parking lot on the doors of an apartment or garage. And when triggered, the watchman will call the police. You can put such an alarm in the apartment if you are friends with your neighbors. Even if you go on a hike, it is not a sin to spread a security loop around the camp at night in case of wild animals or strangers.

First scheme electronic alarm is simple to the extreme, it couldn't be easier. This is just one transistor, resistor and an executive relay. If an audible alarm is supposed, then instead of a relay, an audible siren or a howler is turned on.

Principle of operation: The security loop is a thin wire, or closed contact. When the wire is intact (or the contact is closed), the base of the transistor is grounded and the transistor is closed. No current flows between collector and emitter.

If you break the guard wire, or open the contact, the base will be connected to the power source through the resistor R1, the transistor will open and the relay (or siren) will work. It can be turned off only by turning off the power supply or by restoring the security loop.
Such an alarm can be used to guard your belongings, for example. A reed switch is used as a security contact, the alarm is hidden in the side pocket of a bag or backpack, and a magnet is placed nearby. If the magnet is removed from the alarm itself (move the thing), the siren will squeal in all voices.

Second circuit with more advanced custom functions

As in the first case, a security loop, a normally closed (in armed mode) contact or a reed switch closed by a magnetic field serves as a sensor. If the loop is violated, the alarm is triggered and its operation continues until the power is turned off. Loop recovery does not turn off the alarm, it will still continue to work for some time. The alarm has a temporary blocking button, which is necessary for the owner to leave the protected area. The alarm also has a response delay, which is necessary for the owner to turn it off when he enters the protected area.

Let's analyze how the circuit works. Before arming the alarm, you must turn off (open) the S1 switch. It must be installed in a secret place near the entrance. You can use, for example, a hidden reed switch, which closes - opens by rearranging an object with a built-in magnet, etc. This switch blocks the operation of the system and it stops responding to a loop break. When leaving, the switch S1 opens and the capacitor C2 begins to charge through the resistor R2. Until the capacitor is charged to a certain value, the system is "blind". And you have time to leave the facility by restoring the security loop or by closing the contacts. Choosing the values \u200b\u200bof the resistor R2 and capacitor C2, achieve an acceptable exit delay for yourself.

If the security loop is violated, then capacitor C1 will start charging through the resistor R1. This pair creates a slight delay in the alarm, and the owner has time to neutralize it by turning on the S1 switch. It is necessary to select the resistor and capacitor values \u200b\u200bfor a comfortable response delay time.
If the loop is violated by an intruder who does not know how to turn off the alarm, then some time after the loop is broken, the alarm will be triggered (both inputs of the D1.1 element will be logic "1", respectively, at the output "0". Having passed through the inverter D1 .2 it will again become "1" and will open the transistor VT1. The transistor will discharge the capacitor C3 and through the inverter will open the transistor VT2, which will make the executive relay work or turn on the siren.

Even if the attacker quickly restores the loop, the siren will continue to work, since the capacitor C3 will be charged for a sufficient time through the resistor R3. It is the denominations of this pair that determine the alarm operation time after the loop is restored. If the loop is not restored, the alarm will work continuously.
Microcircuit - K561LA7, transistors - any n-p-n (KT315, KT815, etc.) Power supply - any with a voltage of +5 - +15 Volts. The executive relay or siren can be connected to a more powerful power source than the circuit itself. In standby mode, the circuit consumes practically no current (at the self-discharge level of the batteries).

Everyone wants to protect their own property, but modern alarms cost a lot of money, but you can make an alarm from scrap materials literally for a penny. All tools can be found in every apartment.

Watch the video and try to make your own alarm yourself

We need:
- a medium-sized syringe;
- stationery buttons;
- scissors;
- rechargeable battery or battery;
- Super glue;
- firecracker;
- electronic match;
- ball from the bearing;

We take a medium-sized syringe, disassemble it by simply removing the valve.

We cut off the nose of the syringe, we no longer need it.

Using the pushpins at the base of the syringe, we make holes opposite each other.

We take a pushpin, wind a wire around it and insert the button into one of the holes made earlier.

Then we take any electronic device that will notify that an intruder has entered our territory. It can be a light bulb that will blink in case of danger or a serena with light effects, we will use an electronic match.

We attach a firecracker to the electronic match and we tie one end of the electronic match to the second paper clip and insert it into the second hole made.

It is very important that when you tilt the syringe, the ball does not roll out of it, but only touches both parts of the push pins.

All our alarm system is ready, all you need to install it and connect the remaining wires.

It will act as follows, if we touch our structure, the ball will roll down and close the wires, the match will light up and the firecracker will explode.

Alexei

A dacha, detached outbuildings in the courtyard of a private house can also become an object of encroachments by thieves. It is impractical to install an industrial security system in them, it will cost more than all things stored in such premises.

But it is not worth leaving it completely without protection, amateurs to profit at someone else's expense, if they do not take away your property, will harm the structure of the building, the restoration of which will require funds. Therefore, many believe that a simple burglar alarm would be the ideal solution; almost everyone can make it with their own hands.

What is included in such a system?

Typically, such models use an IR motion sensor, a siren and other components to assemble the device. But since wired detectors are designed to operate on a 220 V network, it will have to be upgraded and converted to 12 V. For this, a 6 V relay is added to the circuit. Power is supplied to the sensor through a switch. When the device is triggered, voltage is applied to the relay coil, it is triggered and leads to the siren turning on.

If necessary, up to several audio signaling devices can be connected to such a circuit. The presence of a regulator in the sensor allows you to set the signal time after the siren is triggered, usually it is no more than 10 seconds. The circuit is turned off using a special device that is switched with a key.

The considered simple security alarm is one of the most primitive, it is easily assembled with your own hands and is economical in terms of energy consumption. For example, no more than 16 alkaline batteries are required for the winter. Such a scheme works in any conditions and is capable of withstanding even negative temperatures, so it is quite suitable for installation in unheated summer cottages.

Types of homemade schemes

Do-it-yourself assembly and installation of the system has several advantages. It saves money, eliminates the possibility of complicity of the installation company employees, thieves. But most importantly, in the manufacturing and installation process, you will carefully study the structure of the alarm, you will be able to troubleshoot problems yourself, make adjustments to it by connecting additional sensors and improve your design.

We watch the video, homemade security system:

There are several ways to equip a house with a simple burglar alarm, assembled and installed by yourself. The first and the simplest, but at the same time the most expensive one is to invite the employees of a special company who will develop the project, select the necessary equipment, install it and perform commissioning. This option is suitable for residential and warehouse premises, but not suitable for summer cottages, since the costs will exceed the value of the property stored there.

Another way is to buy equipment, carefully study the instructions for its installation and operation, and perform the installation yourself. In general, there is nothing impracticable in this approach.

Moreover, many trading companies are engaged in programming the control panel, which will save you from the need to purchase a programmer, learn the rules of working with it and try to complete this stage of work without outside help.

For the simplest type of signaling, it is required to program the device loops, connect them to the general network and write down the required number of keys for access in the memory. They will be required to disarm and arm the object. In addition, the switching on of the light device is programmed, and with a limitation of the operating time of up to 10-20 minutes and a relay output for dialing a mobile phone.

Watching the video, in addition to the basic mobile phone alarm;

On the market, you can find many GSM modules to send a signal to a specified number when the contacts are closed at one of the inputs. These devices are universal and can be connected to any control panel.

If you are already, then their next step is to connect them to the programmed device, which is easy enough for anyone who is able to find the "plus" and "minus" in the circuit. Again, with self-made installation, you will be able to understand in detail the laying of cables and, in the event of a breakdown, fix it without problems.

Watching a video about the purchased GSM system:

For those who are not satisfied with the wired system, you can choose the wireless option. In this case, the installation is even easier, since you only need to hang the sensors in the required places and insert batteries into them. The advantage of such systems is the ability to operate on one power source for up to a year, and their cost, when equipped with one or two sensors, is low.

The detectors also have their advantages. They can be moved from one place to another, if necessary, without much hassle. The option considered above can be made cheaper by buying used equipment. This option is easily assembled with your own hands.

Another, the cheapest, but also ineffective way is the installation of dummies. Such a system is unlikely to be able to scare a hardened thief, but it will be able to stop the boys who decide to fool around in someone else's dacha.

A project for a homemade alarm - is it necessary or not?

Having decided to install a security system in the house, you have to be the first to solve the issue with the development and execution of documentation. A professionally executed project is the basis for a future system, if its installation is carried out by employees of a special company. But what about those who decided to do all the work on their own?

If you install an alarm in a public place, then the project must be mandatory, otherwise the supervisory services will not accept the system. But the house does not belong to such objects, therefore, to install equipment in it, only a sensor circuit is required, which is necessary for future maintenance.

The simplest circuits - on a time relay

We will only consider two of them. The first burglar alarm for the house, which you can assemble with your own hands, is built on a time relay. It has two groups of contacts, one of which works instantly, and the other after 5-10 seconds. This is necessary so that the owner of the object, when entering it, has time to turn off the system with a special button, which is installed in a hidden place.

Complete shutdown is performed by a special toggle switch. With this design, a position sensor is installed on the door frame. Before entering, a button is installed, which switches the circuit to security mode, after the owner leaves. Typically, such complexes use a 12 or 24 V relay.

Watching the video, in addition to GSM alarm, 12V relay:

The disadvantage of the circuit is the sound of the siren until the alarm is turned off by the button. To eliminate it, the system is supplemented with one more relay, the response time of the contacts in which does not exceed 120-180 sec. After this interval has expired, the siren is turned off and remains in this position until the system is armed.

The second of the proposed do-it-yourself kits is based on one relay. The operating time of the siren in it is set using a relay. And it goes into standby mode after the system is de-energized. In this circuit, a thyristor is used to ensure the fire and electrical safety of the equipment.

It is designed to connect a large number of sensors for various purposes. For example, for glass you can use detectors in the form of strips of metal foil, which are triggered when they are broken. Their connection to a common network is performed sequentially.

It is possible to use other types of thyristors. For example, the model PEV-10 with a power of up to 10 W or somewhat with a lower rating.

If the circuit is broken, the relay will trip, which will trigger the siren or any powerful bell. Additionally, a light bulb can be included in the circuit, which is an auxiliary element that does not affect the operation of the system.

Is this method of protection reliable?

Property protection is becoming the most urgent issue in our time. And the way to solve it depends on many factors, but often the cost becomes the decisive one.

It makes no sense to install an alarm, the price of which exceeds the value of the protected property. For such cases, the ideal solution is to design and install the system yourself.

But will such signaling be effective? In some cases, she will certainly be able to scare off thieves, but for reliable protection it is better to use professional equipment and services of specialists. The use of the console security will not only become a reliable guard, but will also allow you to return funds if, nevertheless, a robbery is committed.

Installation of a GSM alarm system in a country house, in a garage or a private house allows you to ensure the safety and security of property. Management is carried out by means of a telephone, and for DIY installation you need to master all the features of the system.

The principle of operation of the GSM alarm

GSM signaling is a complex of devices that are interconnected by the GSM network and interact through a signal. The elements of the complex are installed at the facility, and the control and reception of signals is carried out using a stationary or mobile phone located at the owner. So you can receive alarm notifications about the intrusion of strangers into the protected object. The system is controlled according to the same principle, but for this you need to send the necessary signal from the phone. As a result, it is possible to activate the work of fire extinguishing systems at the facility, control electronic locks and other elements.

Scope of the security system

Security systems operating over the GSM network are various and are widely used in private houses, garages, summer cottages. The use of car alarms is effective, but such a system differs significantly from a complex for real estate. Small remote warehouses, production facilities or other structures can be easily equipped with such devices. Functional signaling allows you to react in a timely manner to fire or damage to property, to prevent other unpleasant actions of intruders.

Devices, depending on the model, perform the following functions:

• ensuring fire safety of a summer house, garage or other facility;
• control of the availability of electricity in the network;
• control of leaks and blocking of water valves;
• gas pipeline leakage control and system shutdown;
• activation of the siren, as well as heating or watering on the site;
• listening to the premises;
• room temperature control.

The complex of devices can include various sensors, for example, for monitoring the integrity of window panes or smoke detectors. This allows you to vary the functionality of the security system. Therefore, the GSM complex is optimal not only for a summer cottage, garage or private house, but is also used for greenhouses, private facilities under construction and other structures.

Components of the device for home and garden

A simple alarm option does not imply the presence of complex devices, which allows you to create a security system yourself. At the same time, it is necessary to understand the principle of operation of the entire complex. As a result, you can create an effective GSM alarm system for your summer cottage or garage with your own hands. It is so easy to avoid the cost of purchasing expensive equipment.

The following components are required for signaling:

• simple push-button mobile phone in working order;
• ready-made sensor or reed switch + magnet;
• switch;
• mounting wire;
• soldering iron and solder;
• sIM card.

Do-it-yourself system assembly

The security system complex assumes the presence of a control unit with outputs for sensors and sirens. Emergency situations trigger commands that are pre-programmed. For example, if the integrity of the window panes in the house is violated, the system is able to send an SMS message to the owner. Listening to everything that happens in the house is also possible by calling the block located in the guarded house.

First you need to determine what type of sensors are needed at the facility. Devices that detect damage to window glass, as well as sensitive to smoke and an increase in air temperature are in demand. Special motion sensors are also installed on the front door. After determining the types of devices, their location is selected.

The complex of works includes the following stages:

Video: motion sensor alarm

A simple system with a minimum of detail is convenient, but motion-responsive alarms are more effective. The system is easy to create with your own hands, and video guidelines allow you to master the process.

Time relay system

GSM alarm schemes with time relays are different, but simple options are easy to create with your own hands. In this case, the relay is necessary for the sound of the siren, and the design may contain both two and one such element. In the first case, one relay activates the sound notification, and the other element turns it off after a specified time interval. The item has two contact groups. If one relay is present, the shutdown is done manually, i.e. by the alarm shutdown button.

Video instruction for creating a time relay

GSM alarm system, equipped with a time relay, is functional and convenient. The video, which presents the features of installation, allows you to master the rules and principle of operation of the relay.

Disadvantages of a homemade system

Simple assembly, economy, easy operation and the possibility of increasing functionality are the advantages of a home-made alarm system for a summer cottage, garage or private house. The system is not devoid of disadvantages, which are expressed in the following:

• easy blocking of the alarm by unauthorized persons;
• malfunctions occur quite often;
• a large set of functions requires the correct installation of each element;
• a complex system requires careful planning.

Reviews of experts

Experts have different opinions about the effectiveness of homemade devices. The location of the facility is important, as is the type of system. The presence of a siren often makes signaling a method of scaring off intruders, but before creating a system, it is worth considering the feedback from specialists. Comments on the effectiveness of homemade devices are few in number, but contain some key points.

When installing an alarm in an apartment with pets, it is worth considering the reviews of experts:

The motion sensors can be adjusted to a specific reaction height. If your cat does not playfully jump to a height of 2 meters, and the intruder does not climb on his bellies (in this position you cannot even open the closet!), Then the alarm is quite justified. The main thing is that specialists who understand the subject well are engaged in the installation.

Andrey Kotousov

Motion sensors can be configured so that they will be triggered only if an object is moving in the room larger than a certain size. It can be configured so that when an object is moved less than 10 kilograms, there will be no triggers. My relatives have an alarm system in their apartment, including motion sensors. They have 2 cats that walk throughout the apartment, while there were only 2 false positives, and both times when the cats overturned massive objects (once their 4-storey house) the 2nd carpet twisted in the corner. So the main thing is to set it up correctly ...

Mikhail Karpov

https://otvet.mail.ru/question/82855068

DIY project: yes or no?

There is no need to create a project when installing a homemade GSM alarm system. This is due to the fact that the system includes a minimum number of elements that are easily connected and interact with each other. In this case, it is worth determining the location of the main unit, as well as the areas for placing all sensors. A schematic representation of the entire system allows you to quickly make an alarm yourself.

Laser alarm

Homemade laser alarm is an effective security system that is easy to operate. This uses more sophisticated components than GSM signaling. For example, a laser source, resistors and other elements are needed. The principle of operation of such a security system is that when the laser beam is interrupted, the voltage at one of the terminals drops below the reference voltage at the other terminal. At the same time, the voltage level increases at the output of the first operational amplifier, and the resulting pulse can be used to turn on the siren, searchlight and other devices.

Scheme selection

An alarm based on a laser beam is generated according to a scheme. There are many options of varying complexity. The choice depends on your electronics skills. For example, an effective timer system is quite simple and is actively used for the protection of private objects.

System creation

To install a laser alarm with your own hands, you need to prepare a BT169 thyristor, a laser, an LED light bulb, a capacitor, 47k resistors, a photoresistor or LDR. Installation includes the following stages of work:

Pros and cons

Laser signaling is distinguished by such advantages as efficiency, long range, reliability and prompt response to emergency situations. To create a system with your own hands, you need simple elements that are easy to purchase. The source of the laser beam is an ordinary pointer that produces a beam of red or other color. The finished device makes the assembly process simple.

The signaling has disadvantages such as the complexity of the assembly circuit, requiring knowledge and skills in the field of electronics. It is important to correctly mount and connect additional elements in the form of a timer or other devices to the system.

Video: laser alarm installation

Detailed video instructions allow you to master all the features of self-assembly. In this case, the signaling will be economical, high-quality and effective in use.

A GSM security system or a laser complex allows you to ensure the safety of property and the security of the facility. For a summer cottage or garage, it is easy to create a system with your own hands, but it is important to follow the installation rules and use high-quality components.