This Simplest Blown Fuse Indicator Circuit shows if fuse is good or bad without checking it by hand. If fuse is okay then green LED turns ON. If fuse blows then green LED goes OFF and red LED turns ON. That means fuse is bad and needs to change. Circuit Working: Parts List: Component Description […]
Indicator Circuits
Using a Reed Switch as a Current Monitor Circuit
Reed switch is small switch which works with magnet. When wire is near it has current and it makes magnetic field. This magnetic field make reed switch turn ON or OFF depends how it is made. It help to know if current is there. Circuit Working: Parts List: Component Type Description Quantity Resistor 470Ω 1/4 […]
Simple LED Voltmeter Circuit
This Simple LED Voltmeter Circuit is like small battery checker but with cool lights. Not like phone bar this one is used in many tiny lights like LEDs to show how much battery is still there. More lights turn ON when battery is more full and each light become ON at different voltage. It also […]
Simple Water Level Indicator Circuit using IC ULN2004
This Simple Water Level Indicator Circuit using IC ULN2004 work like small helpers for our water tank. It uses one special chip named as ULN2004 to control many things together. This chip can work with big electricity but here it only control lights. The lights show how much water is inside the tank. So with […]
Simple 2 LED Battery Status Indicator Circuit
This Simple 2 LED Battery Status Indicator Circuit work like gas meter but for battery. It uses LED lights to tell how much power battery still have. One light mean battery is full another light mean half power and last light mean time to charge. It use small parts like resistors, Zener diodes and transistors […]
Water Level Indicator Circuit with Digital Display
No need to check water with normal stick. This Water Level Indicator Circuit with Digital Display use sensor to check water level. Then it show number from 0 to 9 on small screen, like mini calculator. So we can always see what level the water is in the tank. With this there is no need […]





