: Category: Alarm Circuits

Touch Alarm Circuit

When signal came from touch sensor 555 send a pulse to transistor wich activate relay(RELE)

Touch Alarm Schematic

touch alarm PCB

Components

R1-100K
R2-4K7
R3-10M
R4- *SEE NOTE
R5- *SEE NOTE
P1-100K
D1-1N4148
LED1-LED2 - 3mm
C1-47uF
IC1-555
T1-2N2222 or 2N3904
RELE 6V-12V

*NOTE IF VOLTAGE =9V R4-390 R5-390 IF VOLTAGE =12V R4-1K R5-1K