This be Water Sensor Alarm Circuit for warn the water level , by when sensor point touch the water. The circuit have a voice loud warn hear immediately.
By this circuit uses the integrated circuit LM380 , usual use be power amplifier IC the small-sized , seek buy easy , be usable not difficult. For friends loudspeaker choose use 8 ohm small-sized all right. For power supply source 9V sizes arrive at 12V all right.
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