This non-contact ac voltage detector circuit, using digital IC CD4060 as main components and resistor and LED display only. it is use 9V battery as power supply.
Use low voltage so safe. I am boring old buzzer. When use AC line, danger of leakage power in the heavy rain, 3 circuits can help you!.. .......
This is IC 4060 Timer circuit. When rises time that is set, Suppose set 5 minutes time. after all time to 5 minutes. the circuit will emit a sound of buzzer once. [...]
We like Door buzzer sound circuit, in two-tone. It uses a low voltage power supply so it is safer. It saves if use battery. See the advantages, do not wait!