buzzer.txt

THE BUZER USED IN THE CIRCUIT USES A 555 IC IN THE ASTABLE MODE
OPERATING AT A FRWEQUENCY OF APPROX 600 HZ
RESISTOR VALUSE ARE RA =10 AND RB =100K WITH C1=.01 MFD
THE OUT PIN 3 IS CONNECTED TO A PIEZO ELECTRIC BUZZER OR A 8 OHMS
SMALL SPEAKER LIKE THE ONES USED IN POCKET RADIOS TO GENERATE THE TONE
SINCE THE CICUIT WILL ALWAYS BUZZ, PIN 4 ( RESET PIN) IS PULLED
DOWN TO GND BY A 10 K RESISTOR TO KEEP IT IN RESET STATE.

IN THIS CONFIGURATION THE BUZZER WILL NOT SOUND.

BUT IF A 5V IS GIVEN TO PIN 4 THE 555 GETS ACTIVATED AND THE
BUZZER WILL SOUND.

IF RB IS CHANGED TO 10 K THEN THE FREQ IS 4800 HZ.

END ..........