WELCOME

PREPARED BY :-SAURAV SHEKHARSACHIN RAJAKVIJENDRA PAWARSANDESH GOHATIYA

COLLEGE:- BANSAL COLLEGE OF ENGINEERING, MANDIDEEP

 One of the inflected forms of the Old English noun sceadu, translatable as either "shade" or "shadow“, was sceaduwe ; this form was used when the word was preceded by a preposition (as in in sceaduwe, "in the shade, in shadow")

early 14c., from O.Fr. alarme (14c.), from It. all'arme "to arms!" (lit. "to the arms"). An interjection that came to be used as the word for the call or warning (cf. alert)

ORIGIN OF TERM “SHADOW ALARM”

This is the circuit of a simple burglar alarm  that produces a loud beep when somebody crosses a protected area or door. The circuit is highly sensitive and can detect the shadow of the moving person from a distance of 1 meter. It does not require an aligned light beam to make the circuit standby. It is portable and can be places anywhere for monitoring.

What Is Shadow Alarm ?????

CIRCUIT DIAGRAM

ABSTRACTOur mini-project is to design and check the functionality of ‘SHADOW ALARM’ circuit. Shadow Alarm is opto-sensitive circuit that sounds an alarm whenever a shadow falls on it. Now a days it is widely used in aspects of security systems, where security is our main concern .So it can be used at night by shopkeepers to protect the valuables in their showrooms. It can also be used to provide security at warehouses(go-downs) where storage and protection of various types of goods is main concern, and works good for home-security too. A dim lighting in the room is necessary to detect the moving shadow. Unlike opto-interruption alarms based on light-dependent resistors (LDRs), it does not require an aligned light beam to illuminate the photo-sensor.

1. IC’s IC1 741 IC2 NE555 IC3 UM3561 IC3 LM7809

2. TRANSISTORS T1 L14F1 T2 BC548

3. RESISTORS:- 4. CAPACITORS:-

5. PRESET:-

6. LED :-

7. RECTIFIER:-

8. ZENER DIODE :-

9. LOUD SPEAKER :-

10. TRANSFORMER :-

11. SWITCH :-

COMPONENTS USED

LI4F1 PHOTO TRANSISTORThe L14F1 is silicon photo darlingtons mounted in a narrow angle. They are also the most sensitive photo sensors which also detects the moving shadows. It’s tolerance limit is ±.010 with operating temperature -65 to +125 °C. The collector to emitter breakdown voltage and collector to emitter voltage both are 25 V.

IMPORTANT COMPONENTS

IC UM3561

UM3561 is an excellent ROM IC that can generate Multi siren tones simulating Police siren, Ambulance siren, Fire brigade siren and Machine gun sound. This 8 pin low power IC can work down to 2.4 volts.The UM 3561 is a low cost siren generator designed for use in toy applications. The IC has an inbuilt oscillator and tone selection pins. It is easy to make a siren generator with only a few external components. Only one external resistor and a speaker driver transistor are sufficient to make a simple siren generator.

This opto-sensitive circuit sounds an alarm whenever a shadow falls on it. So it can be used at night by shopkeepers to protect the valuables in their showrooms. A dim lighting in the room is necessary to detect the moving shadow. Unlike opto-interruption alarms based on light-dependent resistors (LDRs), it does not require an aligned light beam to illuminate the photo-sensor.

The circuit is powered by a 9V PP3 battery and uses the most sensitive photo-sensor L14F1 to detect shadows. It is portable and can be used at any place that is to be monitored. Op-amp μA741 (IC1) is used as a voltage comparator. Its inverting input is biased by the voltage obtained from the junction of 100k resistor R1 and the collector of phototransistor T1. The non-inverting input of IC1 gets a controlled voltage from potential divider R2 and VR1.

CONT….

HOW IT WORKS ????

In the presence of ambient light, the photo transistor conducts and the inverting input (pin 2) of IC1 gets a lower voltage than its non-inverting input (pin 3). This makes the output of IC1 high, which is indicated by the glowing of LED1. When a shadow falls on the photosensor, the output of IC1 goes low. This low pulse triggers the monostable (IC2) designed for a delay of 51 seconds using R6 and C3. The output of IC2 is used to light up LED2 and activate the alarm.

Slide switch S2 is used to select either the buzzer or siren. When it is towards left the buzzer beeps, and when it is towards right IC UM3561 (IC3) activates to give a loud alarm simulating a police siren. Resistor R8 and zener diode ZD1 provide 3.1V DC to IC UM3561. The circuit is easy to assemble as it requires only a few low-cost components. Enclose it in a cabinet with the photo-sensor inside. Drill a 5mm hole on the front panel of the cabinet to let ambient light fall on the photosensor. Adjust potmeter VR1 (47k) until LED2 stops glowing and the buzzer stops beeping while LED1 glows. This is the position of VR1 to be maintained for that particular intensity of light. LED1 will continue  to glow even when a shadowis detected.

The circuit is now ready to use. To test it, move a paper in front of the unit. If LED2 glows along with the beep of the buzzer, it means that the photo-sensor has detected a shadow.

The main advantage of this circuit is that unlike opto-interruption alarm based on light-dependent resistors (LDRs), it does not require an aligned beam to illuminate the photo-sensor.

This circuit is easy to implement and all the components used in this circuit are available in the market.

ADVANTAGES

Even though you may set your alarms when you leave, there is always that one chance that you may forget.

Most professional burglars are very familiar with home intruder alarms and know exactly how to deal with them.

If the alarm is set and the burglar happens to trip it, he will immediately flee from the area and move on to a different home.

DISADVANTAGES

It is easy to understand that a security alarm system provides peace of mind when you’re away from your place of business, and is there to meet insurance requirements while minimizing burglary loss.

However, it is also a tool to protect your livelihood and that of your employees.

It can be used at night by shopkeepers to protect the valuables in their showrooms.

It can also be used to provide security at warehouses where storage and protection of various types of goods is main concern.

This circuit can also be used for home securities too.

APPLICATIONS

In future we can develop more security systems with more reliability.

we can also reduce man work.

can make it more economical.

FUTURE ENHANCEMENT

The circuit has to found to have greater application in security reliable and less expensive and is guaranteed to perform the best of the duration of their life time. Our team effort and guidance of lecturers have helped us in completion of our project. This project is accessible to anyone with an average expense and a bit of dedicated work, as we have realized in materializing it. The project has been an enriching experience for us. We conclude that this project will be useful to everyone.

CONCLUSION