http://mskrao.weebly.com
http://mskrao.weebly.com
1. INTRODUCTION
In this busy world, minimizing the human effort and time is the ultimate aim of technology. It may be frustrating when a tired person gets into bed and remembers he had forgotten to switch the bed light off. The project ‘automatic night lamp with morning alarm’ helps avoid this problem by switching on an LED itself when it detects darkness in the room. The LED serves as a bed lamp or a reading lamp provided a reflector. In the morning the LED switches itself off and sounds a melodious alarm to wake the user. The user can manually switch the alarm off.
The project makes use of an IC NE555 timer configured as a monostable multivibrator. An LDR is used to control the trigger of the multi-vibrator. During daytime, the trigger is high and the multi-vibrator is in OFF condition. During the night the trigger goes low and the device starts to operate i.e. the LED is ON.
UM66 IC is used to generate the melody for the alarm. An LDR is used to control the switching of the alarm. During night time, the LDR resistance is high and the alarm is in OFF state. When daylight is detected, the resistance goes low and alarm switches ON. It can also be switched off using a manual switch.
This project can be effectively used for automatic lighting of bedrooms, hostels, streetlights, garden lamps etc to save power and reduce human intervention. It is of low cost and requires only a trivial amount of DC power to operate.
1 http://mskrao.weebly.com http://mskrao.weebly.com http://mskrao.weebly.com
http://mskrao.weebly.com
http://mskrao.weebly.com
http://mskrao.weebly.com
2. CIRCUIT DIAGRAM
Description: The project makes use of a NE555 timer IC configured as a monostable multivibrator. An LDR is used to control the trigger of the multi-vibrator. During daytime, the trigger is high and the multi-vibrator is in OFF condition. During the night the trigger goes low