The internet is full of circuits that get copied from website to website without anyone checking if it is a good or usable circuit or not. Even though many of these circuits are fine, there are also many that don’t work or contain mistakes. Therefore, you cannot simply trust what you find online, and you must verify every circuit you pull from the internet. Even better is to understand them. To achieve this, always remember that LTspice is your friend.

The circuit presented in this video is of the kind that pops up in many places when you search the internet for something like a car bulb or 12 V lamp flasher circuit. I discovered it when a version of it was posted at the Elektor Labs project website. None of the websites that have the circuit try to explain how it works or provide some technical details. It may be that nobody knows how the circuit works, or maybe nobody cares about how it works.

LTspice to the Rescue!

With the free circuit simulator LTspice it is easy to analyze the lamp flasher circuit and this video presents the results. You may be surprised...

 

Resources

More About Oscillators

Want to learn more about oscillators? Check out these resources:
 
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