Cool Electronic Projects

By V. Subhash

 

If you are learning electronics or thinking of it as a future hobby, here are some fun home-improvement projects to begin with. They:

• will be extremely useful (particularly in emergencies),

• will not waste your time or money and

• are quite easy to make.

Just one of these projects uses AC (alternating current). The rest work on DC (direct current) and are safe for kids (if you think soldering is safe).

These projects are good for the environment too, as they reuse electronic parts that would have been discarded. If you are a prepper or survivalist, then you will be happy that all the projects will run off-the-grid, as they can consume renewable energy.

For the tinkerer, there are projects that add MORE POWER than what the manufacturer had designed for. For the parent of lazy children, there are annoying alarms that can wake up the dead.

Everything is explained in plain English. Simple and straight-forward. No exotic projects or obscure concepts.

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• Language: English
• Publisher: V. Subhash
• Release date: Sep 23, 2023
• ISBN: 9798223570851

V. Subhash

V. Subhash is an invisible Indian writer, programmer and cartoonist. In 2020, he published one of the biggest jokebooks of all time — 2020 FRESH CLEAN JOKES FOR EVERYONE. He followed this jokebook with a tech book on the free multimedia-editing utility FFmpeg and a 400-page volume of 149 political cartoons. Although he had published a few ebooks (using off-the-shelf software) as early as 2003, Subhash did not publish books in the traditional sense until 2020. For over two decades, Subhash had used his website www.VSubhash.com as the main outlet for his writing. During this time, he had accumulated a lot of published and unpublished material. This content and the advanced book-production process that he had developed helped him publish 21 books in his first year. In February 2023, Apress/SpringerNature published his rewritten and updated FFmpeg book as QUICK START GUIDE TO FFMPEG. Thus, by early 2023, Subhash had published 30 books! In 2022, Subhash ran out of non-fiction material and tried his hand at fiction. The result was UNLIKELY STORIES, a collection of horror and comedy short stories. After adding new stories to this fiction title (for its second edition), Subhash plans to pause his writing and move on to other things. Subhash pursues numerous hobbies and interests, several of which have become the subject of his books such as COOL ELECTRONIC PROJECTS, HOW TO INSTALL SOLAR and HOW TO INVEST IN STOCKS. He was inspired to write his jokebook after years of listening to vintage American radio shows such as ‘Fibber & Molly’ and ‘Duffy's Tavern’. For more, check out: www.VSubhash.in

Book preview

Introduction

When I was in school, a classmate told me that he had built a radio that could run without a battery. He said that there was enough energy in medium-wave broadcasts that they could power a headphone! I was fascinated. I asked him how much it cost him and he quoted a fairly large amount just for the parts. My uncle had given me just that kind of cash as a gift and here was an opportunity to spend it. It was too late when I realised that my friend had only read about it and had never actually built it. My money was gone and I bid goodbye to electronics as a hobby forever… until about a decade-and-a-half later.

The publisher of my Linux magazine also had an Electronics For You magazine. Its subscription ads rekindled my interest. I bought and read the Electronics For Dummies book. I then bought a soldering kit and electronic components that the book authors had suggested I start with. I also did some research and found that the radio that my friend had hoped to create was known as a ‘crystal radio set’ and required a special kind of ear-piece typically used by the hearing-impaired. It seemed expensive and I did not pursue it. I settled for a simple mono amplifier with the ever-popular LM386 chip. This IC was louder than I expected. For my next project, I bought a cheap Chinese-made car MP3 player module and built a tiny boombox. I also created powerbanks and solar chargers to drive such speaker thingies. I built a whole of lot of DC-based off-the-grid survivalist stuff, not because I am a survivalist but because the electricity supply in my area is very unreliable.

Most of my projects are low-cost, recycled or made from extremely cheap kits. I use them almost every day. I wish I had not ignored electronics as a hobby for so many years. In this book, I show how easy my projects are to build and how you can embark on a similar journey… hopefully much earlier than I did.

Important Warning

This book describes DIY electronic projects in graphic detail. These projects were created for their utilitarian home-improvement value and were never intended to be showcased in a future book… too late.

Warning

USB-powered LED Light

You can build an LED lamp that can be powered by the USB port of your computer. You will need a USB plug connector for this. For online purchase, search for ‘ 4-pin Type A USB 2.0 plug’.

USB-powered LED lights

An LED (light-emitting diode) requires around 3 volts. The USB port provides 5 volts. To protect the LED, you need to add a 220Ω resistor. (Ω = Ohm)

Construction: Solder the first pin of the USB plug to one lead of the resistor. Solder the other lead of the resistor to the positive lead of an LED. Solder the negative lead of the LED to the fourth or the ground pin of the USB. Use the continuity function of a multimeter to ensure that the USB pins are not connected to each other or to the metal sleeve. Insert the USB plug into an USB port of a phone charger. (Do not use your computer ports for testing.) If the LED stays lit up, it is