Introduction: How to Identify PNP and NPN Transistors (with a Simple Circuit)

Picture of How to Identify PNP and NPN Transistors (with a Simple Circuit)
In this project I’ll make one of the easiest PNP and NPN circuit identifiers ever. You’ll see how easy It is to make one! I've also posted on my website a bit of the theory about PNP and NPN Transistors I would recommend you to read it  first.

This project is great to learn more about:
  • Transistors
  • Simple DIY Circuits
  • PNP and NPN Transistors
If you want more Electronics Projects and Tips make sure you visit My website:
If you just want to see my project working you can see this video:


Step 1: Parts Required

Picture of Parts Required

1x LED
1x Pushbutton
1x 1k Ohm Resistor
1x 10k Ohm Resistor
1x Breadboard
1x 9V Battery (and Battery Clip)
Some Wires

Step 2: Schematics

Picture of Schematics

Just follow these Schematics and you'll be fine! :)

Step 3: Optional Step

Picture of Optional Step

I've decided to Solder everything in a Stripboard and that's the result. This step is optional you might want to use only the breadboard.

Step 4: Final Product

Picture of Final Product
Make sure you visit my website for more Arduino Projects and Electronics tips
hanks for reading I really appreciate you time and support.
Please share my work.


RichardR171 (author)2016-07-18

Which legs are collector, base, and emitter?
Which resistors go where?

laith mohamed (author)2015-09-05

That is awesome

kailash.mehendale.7 (author)2015-04-11

This was helpful for me. Thanks.

ashbash100 (author)2014-11-20

Just for other people, if the light turns on without you pressing the button, it is PNP. Otherwise, it is NPN.

Abirboy (author)2013-10-21

this is super helpful for me ..Thanks

RuiSantos (author)Abirboy2013-10-23

Thanks for taking the time to leave your feedback!
I'm glad I could help.

crazy_thiago (author)2013-07-30

The slide swith on bread board on "opitonal step"
Is to on/off all sistem?

About This Instructable




Bio: Author, Blogger, Electronics Enthusiast and Entrepreneur. For complete Electronics Projects and Tutorials go to:
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