RAIN
DETECTOR
ALARM
1) Single sided copper
PCB board
2) NPN-TRANSISTOR
BC547
3) LIGHT-EMITTING
DIODE
4) 12V ACTIVE BUZZER
5) WIRES
Mark some vertical lines on
PCB with permanent marker very
similar to the square wave.
Then scratch the lines with
the cutter. The purpose is to make
two separate areas on PCB. Now,
the electric current does not go
from one area to another. When
the rain falls on these transition,
the current flows from one area to
another.
SOLDERING IS BASIC
PHENOMENON IN THE
ASSEMBLING