SIGNALS SPECTRA AND DIGITAL PROCESSING
(MORNING LIGHT SENSOR ALARM)
Submitted by:
Jayvee M. Celeres
John Cedric T. Monteza
Submitted to:
Mr. Francis Wednesday G. Samonte
Submitted Date: December 20, 2014
AMA COMPUTER COLLEGE – PASIG
I.
Objective:
The researchers decided to do this device for the heavy-sleepers to wake up. After
experiencing multiple times of late for work, school, and other early morning schedules. Alarm
clocks serve as reminders to rouse people from their night’s sleep or a short nap. Depending on
the clock’s design, the alarm goes off with sound, light, sensors, or buzzers to alert the person of
the signal. To stop the alarm, most clocks have some button that needs to be pressed. Other
clocks automatically stop if left alone from long enough.
II.
Design:
A. Materials Needed
9 Volts battery input
Resistor 1 - 1k ohms
Resistor 2 - 330 ohms
Resistor 3 - 330 ohms
Diode 1 - BC547
Diode 2 - BC547
LED
LDR (Light Dependent Resistor)
Relay
B. Schematic Diagram
Black Diagram of Morning Light Sensor Alarm
Active light control by LDR and BC337
This is automatic light circuit when be become dark. It by use LED Lamp, be a place
gives the light and this circuit has small-sized use volt supply 3V only.
The work of the circuit be when there is the light affects LDR1 will valuable the resistance at
LDR1. It be down make Q1 work be born volt at fall straddle a pin C of Q1 compare with
Ground be valuable a little more voltage bias to make Q2 work. By have D1 serial with a pin B
of Q2 make volt at pin C of Q1 compare with ground must use volt about 1.4V arrive at make
Q2 work. But when LDR1 no the light will make to is valuable the resistance more and more
until make to have no current flow get along well with B of Q1 make Q1 do not work. Then have
current flow through R1,D1 get along well with pin B of Q2 work cause LED1 stick bright. The
part , VR1 , parallel connection with , LDR1 , as a result , for take keep fine the rapidity in taking
light of LDR1
Opto-Tone (Control sound by light)
The Opto-Tone (Control sound by light) circuit with IC 555 and sensitive light by LDR.
Light Dark Detector Alarm by IC 555
Today we come to see the circuit detects the light by have a voice warn. When meet the
light or be become dark depend on using S1 ( follow the circuit ). For this my circuit uses
the integrated circuit IC 555 be pillar equipment again. You can choose can use many the
number be LM555 or NE555 or use the number instead of eat the low beam be IC 7555 all right.
For that circuit when S1 stay in a position . And there is the light shines at LDR (Photoresistor) a
loudspeaker will utter. When S1 stay in a position and have no the light at LDR loudspeaker utter
also. This easy good circuit friends may have fun IC 555 detector light.
III. Conclusion
The researchers conclude that the device can be use as an alarm clock as long as the
sensor detected a light. The device should be put outside to detect light and the speaker is inside
of the house. Its sensor can also be adjusted to dark sensor so it also can be use as a nightlight.
With its portability, you can carry it everywhere even in your pocket.
IV. References
http://www.technologystudent.com/elec1/lgtdrk1.htm
http://www.eleccircuit.com/light-sensitive-switch-with-ldr-2n2926/
http://www.electronics-tutorials.ws/io/io_4.html