DIY Circuit Component Tester/Checker

Introduction: DIY Circuit Component Tester/Checker

About: A science freak teen


HI guys its Yasin. I will teach u today how to make a circuit component checker. it is very economical and useful. when u want to check a component of circuit e.g Resistor, capacitor, led, etc touch its terminals with wires of checker, if buzzer buzzes it means component is OK but if it does not buzz it means the capacitor, resistor etc is not OK or it is faulty, when buzzer buzzes a only for a while it means the component is ok but you touched its terminals with wrong wires i mean positive wire touched to negative or vice versa. This component checker can also check power cables, charging wires, etc, if buzzer buzzes then wire is OK but if it does not buzz it means they are broken or faulty. Actually meters for checking components are very costly so I made this. So guys lets start....

IMPORTANT: Use atleast 1 metre wire for checking pins (fit 1 metre wire in breadboard and solder or fit thin pins on their end) so you can easily check a component

Step 1: Materials You Need!!


Piezo Buzzer

200k ohm resitor

1 led

9v battery and its clips


Wires for connecting (i will suggest you to buy 1 metre of lan wire peel of its cover and use its thin wires, they are easy to use and flexible. In circuit diagram red wire means positive and black means negative, you can use any colour but remember which one is positive and which one is negative) (use two wires of different colour for positive and negative)



Electrical Tape or Hot Glue Gun

Pliers (I will suggest you to remove wire cover with nails of hand because lan wires are flexible and you can easily remove their cover but use pliers to remove outer plastic cover of wire)

Step 2: Circuit Diagram!!

Just follow this circuit diagram. Fit led, Buzzer correctly on breadboard i mean positive terminal of led and buzzer goes to positive terminal of battery and negative to negative. long lead of buzzer and led is positive and short one is negative.

Please give me feedback in comments and if u have any confusion just ask in comments. This is my first project. hope u guys like it....

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    3 Discussions


    3 years ago

    Guys one important thing plz dont use this with A.C current electronics. Check them when they are turned off and they are not plugged in. For checking A.C current electronics just touch checking pins of checker with legs of switch. But you can check charger circuits, or ac to dc circuits (5v to 30v) when they are plugged in, but check their components when they are unplugged.


    Reply 3 years ago

    Thanks for your feedback and one thing plz don't use this checker with A.C current outlet. If you want to check A.C current power cables don't plug them just touch component checker terminal with legs of switch. Use with A.C current things when they r turned off and their are not plugged in.