The proposed device car alarm systems (as) performs almost all the necessary functions, contains scarce parts and can compete with industrial systems.

UAS is powered by the car ignition (+12V), and with the loss of her continues to function normally, as it has internal source. The UAS scheme is shown in Fig.1. (LW 45)

Each correct connection of the electronic key into the slot X1 is accompanied by a short run of the siren and flashing the Parking lights of the vehicle, as well as the alternate transition UAS mode "Protection" in the "Off"mode.

The "Off"Mode

In this mode, the device consumes negligible current, and all the vehicle's electrical system is in normal mode. The UAS sensors blocked, and the led is off.

The Security Mode Is

Current consumption does not exceed 5 mA. All sensors are activated, the led flashes with a frequency of 1.4 Hz, ignition system and starting the engine of the vehicle is locked.

UAS goes into "Alarm",when one of the sensors. In this case, immediately turn the siren, flashing Parking lights (f=1.6 Hz), and attempt to start the engine ends in failure. Power consumption is less than in this mode 2 A. In the "Alarm" UAS will be with another 20 under the condition that each sensor has returned to its original state. If not, dvadtsatisemiletny the cycle will be repeated to return the sensor to its original position. Translate UAS in the "Off" mode from any state only by a key.

The UAS scheme contains:
- DA1, R1...R4, C1, PA1-position sensor, is made on the basis of the microammeter. It provides the arming at any initial position of the body;
- DD1, R6 R13... - receiving part of the electronic key;
- R10'...R13'-a portable electronic key. A logical "1" at pin 10 DD1 appears only when the following terms are met:
This is the "highlight" of the entire scheme. For simplicity, it is convenient to take the value of all resistors R10 R13...and R10'...R13' is equal to 10 ohms.
- VD1...VD4 - protection elements of the scheme when applied to X1 voltage of 220 V. In this case, they will just die without damaging the remaining circuit elements;
- SB - pole contactors. They are mounted on the doors, hood, trunk. The sensor closes when you try hacking;
- DD2.1, C3, R5 is a single-shot provides suppression of interference from the electronic key for normal operation of the counting trigger DD3.1;
- DD2.3, R16, R19, R20, C6, VT1. VD8-element time-delay (20C) in the "Alarm";
- DD2.4, R17, C4, VD10 - elements of a single vibrator - shaper of the trigger pulse siren at each transition of UAS in the new regime;
- DD4.4, R18, R21, C5 - pulse generator (f=1.6 Hz), managing CBE-тoдиoдoмVD11;
- DD4.1...DD4.3, C7 C10..., R22 R28..., VT3 VT6... - electronic siren;
- DD4.1, VT2, K1. K1.1-controls the "size" of the car (P=1.6 Hz);
-K2,K2.1,VT7,VD14, R29 - locking elements of the ignition system and the engine;
- GB1, VD15, VD16, R30 - elements uninterrupted power and charge. From the resistance value of resistor R30 depends on the charge current GB1;
-VD13, C11 C13..., DA2 - the power supply filter and stabilizer +9 V.

Initial reset circuit occurs due to the rapid charge C2 through R14. With DD3.1 to pin 4 and DD3.2 by the pin 10 through DD2.3 are reset to the zero state. The UAS mode is set to "Protection", and all the sensors are activated. A logical "O" from DD3 pin 13.2 disables the siren and "size". A logical "1" at pin 2 DD3.1 enables the generator to DD4.4 (F=1.4 Hz), which periodically includes VD11, and also provides based on VT7 opening voltage. The Economics of relay K2 is activated only when you try to start the engine.

Once triggered one of the sensors SB, UAS instantly goes into "Alarm". This is due to the appearance of a logical "1" at pin 8 DD3.2 through DD2.2. The trigger DD3.2 switches in one state and starts the siren DD4.1...DD4.3. The Contacts K1.1 begin to withdraw with a frequency of 1.6 Hz, providing a flashing tail light. Led VD11 is still flashing, and the engine remains locked. At the same time begins to charge through C6 R20. Once it charged (20), logical "1" through VD8, DD2.3 falls to the base of VT1 and to pin 10 DD3.2. If the sensors are not returned to its original state, then VT1 C6 discharges, and 20-second cycle is again repeated. If the sensors returned in original condition, together with the discharge of C6 is reset trigger DD3.2. UAS again goes into "Protection".

Immediately turn off the UAS can only electronic key. Each correct connection of the key to X1 causes a logical "1" at pin 10 DD1.1 and a logical "On" at pin 11 DD2.1. This causes the switching of the counting trigger DD3.1 to the opposite state. A logical "1" output 1 DD3.1 through VD7, DD2.3 goes to pin 10 DD3.2, it resets and holds in the zero state, i.e. the UAS is in the "Off" mode. A logical "O" o 2 DD3.1 extinguishes VD11 and unlocks the ignition system of the engine.

Reconnect the electronic key brings the UAS back to the Security mode. Each transition of UAS in the new regime is accompanied by a short run siren (0,7) and the flashing of dimensions. It provides a fast charge or discharge through C4 R17 and work elements DD2.4, VD10.

Details and design

The emitter BA1 - any dynamic head 10 watts (8 Ohms) or 20 W (4 Ohms). VT2...VT7 - any of a series KT, KT, KT, KT. Transistors VT3 VT6...mounted on one common radiator through the mica strip. Here is attached and the diode VD16. VT1-any of strict,KT3102, CT. VD1...VD4-any low-voltage diodes with a reverse voltage of 10...20 V....VD5 VD10 - any of a series KD521, KD522, CD, CD. VD12...VD14-any of a series D226, D7 and others for a current of less than 0.1 A. VD15...VD16 can be replaced by CD, CD and others at a current of at least 10 A. R30 - MLT-1, the remaining resistors - MLT-0.125 or MLT-0,25. GB1 - any small-sized battery, preferably no liquid electrolyte. It is installed outside the housing of the AC. X1 is any five-pole connector. It is installed in the rear-view mirror driver or in any other place, but outside the car. VD11 - led red glow AL307 or similar. It is installed under the front windscreen^ so that it is clearly visible from the street. K1, K2, K2' - any relays for the switching current is not less than 5 A. And the contacts K1.1 should be normally open and are connected in parallel across the switch "dimensions" of the car, and K2.1, K2.Mr. normally closed and are connected in a broken wire from the ignition switch to the ignition coil from ignition switch to starter relay, respectively. Relays K2 and K2' can be replaced by one with two pairs of contacts.

The printed circuit Board shown in Fig.2 (LW 37) and shown with side parts. All conduits are shown on the lumen through a fee that is one-sided and contains 10 jumpers. All the conductors on which large current flows, is made as wide as possible and soldered by solder. Propivaetsya and ground bus.

Setting. Typically, the device starts up immediately. Sometimes requires the selection of the resistors of the electronic key. To do this, by making the voltage at the circuit, the selection R13 achieve the appearance of a logical "1" output of element DD1.4. Similarly, R12, achieving the appearance of a logical "1" output DD1.3, etc. Resistor R4 set the required sensitivity of the sensor the position of the body, but this is done when the UAS is already installed on the car.

Author: A. Chistov; Publication: N. Bolshakov,


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