Nuts & Volts - July 2004

But Don’t Pass Up Conventional Electronics

Trying It Out

Once the temperature switch is calibrated for a specific temperature, you can test the switch by heating the LM34 with a hair dryer. You can hook up an LED on the output (Vout). Once the temperature reaches the specified point, your LED should go on and stay on until the temperature drops again.

Just like the flashing LEDs, this circuit is relatively easy to build without a microcontroller. You can use this circuit as it is or modify it to suit many different purposes that you may have. You can also learn a great deal about how comparators work. At the very least, it will hopefully spur many ideas on how you can make comparators work for you.

My advice to anyone getting started in microcontrollers and electronics is to get a breadboard, some basic electronic parts (get a grab bag or two), and start experimenting.

To start experimenting, keep reading Nuts & Volts and grab a book or two on the basics of electronics. Some of the best books I found for beginners are the Forrest Mims books from RadioShack. My Forrest Mims book is very old and beat up, but it’s never very far from me when I experiment. There are also some really great websites out there that can help. Just like I said at the beginning of this article — microcontrollers are great! Try not to use them as a crutch and, instead, use some of those conventional electronics that have been around for years. Happy project building! NV

Easy as Pie

These two circuit examples can be used as stand-alone circuits or they may be used in conjunction with other circuits. They can completely replace the use of a microcontroller. At the very least, these circuits can take a significant load off of your microcontroller-based project. The examples I have shown you are only part of what is available for the electronic hobbyist; they are only my ideas and certainly there are many others.

About the Author

Ever since I was about 10 years old, I have been interested in electronics. I went to school to become an electronics engineer, but decided to keep my electronics interest as a hobby instead, so I went into computer programming. Currently, I am a web developer and I love what I do. My favorite electronic device is the microcontroller because it involves my two loves (electronics and programming).

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