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Crystal Radios are a Fun Electronics Project for Kids

This is a simple crystal radio. It requires no battery or any power source for that matter.

This is a simple crystal radio. It requires no battery or any power source for that matter.

A ham radio QLS card, from King Hussein of Jordan

A ham radio QLS card, from King Hussein of Jordan

Old School Electronic Fun

Kids today still play around with radio, however most of them just don't realize it. Modern-day gadgets such as smart phones are really just radios. We use radio for our Bluetooth headsets, GPS navigators, remote control toys and to connect our tablets and laptops to the internet.

I first became fascinated with radio at the age of about fourteen, after my uncle gave me a crystal radio kit for Christmas.

At first I really didn't know what to think about the gift, since I had also received a brand-new Sony AM/FM stereo for Christmas. The Sony was cool looking, sounded great and best of all it was loud enough to annoy my parents, which is something most teenagers seem to delight in. On the other hand, the crystal radio set that my uncle had given me consisted of several rolls of copper wire, a cardboard tube, a small earphone and a small diode.

For several weeks after Christmas, the little crystal radio kit simply remained in its box up on a shelf in my room. You see, in those days, boys such as myself played outside for most of the time, and actually enjoyed it! We spent our days fishing, exploring, building forts and playing all sorts of outdoor games in the physical world, and considered staying in our rooms as punishment. How things have changed! After one session of outdoor "war games" with my childhood friends, one of us came home with a mother's worst nightmare, an eye injury. It turned out not to be as serious as it looked, yet we were grounded.

We would have to spend several hours each day in our rooms, which to us seemed like some sort of punishment. In those days our rooms didn't feature our own computer connected to high-speed internet, or a flat screen TV with the latest movies, or for that matter even any handheld electronic video games.

Making The Most Of A Bad Situation

After a few hours of sulking in my room, I gradually accepted my fate and decided to make the best of it. From up on the shelf I pulled down the box containing my uncle's crystal radio kit and started reading the instructions on how to assemble it. If it worked as advertised, I would at least be able to pick up some music to listen to during my incarceration.

The kit, made by Radio Shack, was actually very easy to put together. It featured a system of spring - type connectors and all one had to do was bend them over and insert the wire to make a connection. The instructions stated that some kind of grounding system was required, such as a water pipe or metal object connected to the earth. Since our home's water heater was near my bedroom, all I had to do was run one of the small wires under the door and attach it to a screw on the water heater.

The next thing that the crystal radio kit required was an outside antenna. Ideally the antenna was supposed to be strung between two glass insulators and placed as high above ground as possible. Not being allowed to leave my room, I would have to make do with the metal screen on my bedroom window.

After assembling the contraption according to the instructions, I attached the small crystal earphone to the set and placed it in my ear. At first I heard nothing, but as I moved the copper tuning coil across the cardboard tube, I began to pick up a local rock station on the AM band. I was actually amazed that the contraption worked, since it required no batteries or other power source.

Crystal radio kits operate solely on the electromagnetic energy traveling through the air from the radio station. Up until this point I had never really thought about how radio worked and the whole thing began to seem like magic to me. I realized that there were radio waves coming from all over the planet, including television waves, traveling through the air all around us, even going through our bodies, penetrating concrete walls and reaching out into the vastness of space.

Building A Massive Antenna System

Having the small crystal radio set to listen to helped ease the pain of my incarceration and when it finally ended and I was able to roam the greater world once again, I decided to put up an even better antenna for the radio set. In my father's garage I discovered some old automobile alternators, which are used to charge the car's battery.

Having seen them disassembled once before on my father's workbench, I knew that inside each one of them was several hundred feet of small diameter copper wire, which would make the perfect radio antenna. A took apart several of the old alternators and obtained about 1,000 feet of slender copper wire.

Next, I found a roll of duct tape and grabbed a couple dozen old Coke bottles from behind the barn. I proceeded to climb the tallest trees around our home and string copper wire through them using the Coke bottles as insulators.

I knew that my mother would probably frown on wires running into my bedroom window, so I decided to set up my radio station in an old tool shed that was seldom used anymore. I had turned the tool shed into one of my “clubhouses” were my friends and I had once met and planned our “war games.” I attached the new antenna system to my crystal radio and was amazed at the results.

I figured that if the crystal radio worked so well on the 1000 foot antenna, then my AM/FM Sony radio (which I just got back from being impounded,) would work even better. With the 1000' aerial attached to the Sony, I was able to pick up station WLS in Chicago, (about 2000 miles away,) which still featured the "Wolfman Jack" radio program, as well as radio stations in Mexico and Canada.

The Next Christmas

The following Christmas, my uncle gave me an even better gift, a small shortwave radio kit. This one was even harder to put together than the crystal radio kit, however the rewards that were promised on the outside of the box ("Listen to stations from across the globe!") kept me going until it was assembled.

I learned how to operate a soldering iron, and installed each of the tiny parts on a circuit board while following the step by step instructions. After it was completed, I attached the radio to my 1000' long "copper wire and Coke bottle antenna system" and set it up in my clubhouse. Soon I was picking up everything from truckers on CB, who were talking about "smokies," to the BBC in London and even shrimp boats out in the Gulf of Mexico.

I was now officially addicted to radio and became an “electronics nerd.” Of course the next step up from this was to save up all of my lawn mowing money and purchase a real ham radio set that I could use to talk to other radio nuts like me around the world.

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After a few days of searching, I found a used one for sale in the local newspaper and asked my mother to drive me over to pick it up. She was actually supportive of my new hobby, thinking that it was more educational and less dangerous than BB gun and dirt clod wars.

The man who was selling it was a high school science teacher and an amateur radio operator. He had his own "radio shack" in his backyard, complete with dozens of fancy radio sets, all humming with Morse code and the sound of fellow radio operators chatting with each other in all parts of the globe.

Looming above the shack were several huge antenna systems which could be aimed in any direction for better reception. On the wall above the man's radio set was a photo of him sitting in a Red Cross van, operating a mobile communications center in some place that had been destroyed by a hurricane.

Next to that photo was a certificate of appreciation from the crew at the Amundsen- Scott Station at the South Pole. The certificate thanked him for providing the only means of communication between them and their families in the United States while they served for months in the Antarctic. I realized at this point that the hobby was about more than just chatting with people around the world.

Although I didn't have the required ham radio license at that point, I used my new radio to listen in on "hams" from all over the world, while I practiced Morse code, which back then was required to obtain a license.

A Ticket to the World

Soon I was able to talk to people from all over the world who were just as interested in radio I was. Along with this came a fascination for faraway places and a yearning to visit countries such as Australia, Norway and Japan. I exchanged postcards with many of my faraway radio friends, (called QSL cards by amateur radio operators,) and it wasn't long before the plastic holders on my clubhouse wall held cards from more than one hundred countries.

As a teenage amateur radio operator, I was lucky enough to visit with several famous radio hams, including Arizona senator Barry Goldwater, Eagles band member Joe Walsh and even King Hussein of Jordan. (I still have QSL cards from them as well.) At the age of 15 I joined a network of volunteers called MARS or Military Auxiliary Radio System, and began to help overseas military personnel communicate with their loved ones at home using radio "phone patches."

Entering my late teenage years, I began to forget about ham radio as I discovered more interesting things like cars and girls, yet would continue to be drawn back to the hobby over the coming years.

Later on, as an adult living on a sailboat in the Caribbean, using amateur radio, I was able to provide emergency communications and help coordinate relief efforts for an island community which had lost all communications with the outside world after having been struck by hurricane Floyd.

Radio Is Old But Not Obsolete

Today I still own a high-powered ham radio set which I sometimes fire up and use to chat with someone on the far side of the globe. I'll admit however, that I do spend far more time on the internet. With its greater speed, versatility and the ability to send files, images and even remotely view my home security camera while on vacation, the internet has replaced many of the functions that radio once served.

However, I know that if a disaster ever "pulls the plug" on the web, the cell phone system, or any of the other modern gadgets that we think are so infallible, I'll still be able to crank up my little camping generator and fire up my old Yaesu FT-101, and stay in touch with what's left of the world outside.

My hope is, that in spite of the amazing technological inventions like the Internet, young people will continue to have an interest in radio. It is the only form of communication that can span the globe and relay vital information following a major disaster without requiring fallible fiber-optic cables or satellite networks.

Despite being an "old technology," today's amateur radio operators are still experimenting with new communication protocols utilizing orbiting satellites, high speed data and video, as well as continuing to provide emergency communications in the wake of natural disasters when modern communication technology has failed.

Oh, and up on the top shelf of my workshop, in an old dusty box, sits the little crystal radio kit that my uncle once gave to me. I'm thinking about passing it on to some deserving kid who might appreciate the magic of music and voices traveling hundreds of miles through thin air, and entering one's ear with no batteries required.

© 2012 Nolen Hart


Suzanne Sheffield from Mid-Atlantic on November 27, 2012:

My dad, now passed away, was an avid ham radio guy with a huge tower. With the threat of an EMP or worse I have taken up an interest in learning how to use a ham radio. I am prepping and have an app on my IPhone that gives me alerts for everything that may be coming down the pike. Your hub really has inspired me. Thank you for sharing your story, it was both a fun and informative read.

Jeff Boettner from Tampa, FL on September 13, 2012:

Wow, awesome story. You've got me fired up to get my own ham kit. (looking up the yaesu now). Looking to see if you wrote the hub about the coke bottle antenna fire :) , up and sharing this one.

Nolen Hart (author) from Southwest on September 02, 2012:

Very cool Casmiro, seems that you followed a similar path as I did. Thanks for the compliments!

Casimiro on September 02, 2012:

Loved revisiting the old crystal set, and the one in the picture is such a fine example. I once had a small xtal set and it was fascinating. That led to a multi-band SW receiver and eventually to my own ham radio license. Nice hub and I look forward to more of your writing!

William F Torpey from South Valley Stream, N.Y. on August 24, 2012:

I loved the little crystal radio set I got for Christmas in the mid-1940's. It was just an unsophisticated coil, but it picked up several radio stations with a weak and scratchy sound. I was amazed by it -- but it was just a toy to me. I'm not as resourceful as you.

Nolen Hart (author) from Southwest on August 24, 2012:

So am I. Though the radios I buy now cost a lot more than the $3 that a crystal radio set cost then.

tamron on August 24, 2012:

My dad had a crystal radio kit when he was a kid. That is how he got interest in ham-radio.

He is a ham-radio operator now. Great hub!

Nolen Hart (author) from Southwest on August 24, 2012:

Very cool on picking up the German station all the way down in Australia. You must have been very excited!

createmyeconomy from USA, Australia on August 24, 2012:

That is awesome - I made one in 9th grade! 1977 - loved it - picked up a german radio station in my basement!

Nolen Hart (author) from Southwest on August 23, 2012:

Gus, I've heard stories all my life of people picking up radio signals through the fillings in their teeth. Knowing how crystal radio sets work, I think this could be possible...?

Gustave Kilthau from USA on August 23, 2012:

Howdy doodlebugs - I enjoyed your adventures beginning with your crystal radio set.

I bought one of those kits when I was a kid (last year?) and I think it cost me $1.98 or thereabouts. We had the biggest of the CBS radio transmitting towers close to where I lived. Its signal drowned everything else out, but I can state that it came in a-booming loud, even though I had but one earphone. I used to stow the crystal radio away in a cigar box under my bed of a morning. One day my mother told me that she had the daylight scared out of her - believing that there was a "man under my bed." No need to ever turn those things off, was there?

Today you can still buy crystal radio kits, but they come packaged with the crystal diode already touched together for you as a component part. We had to fiddle with those cat whisker deals.

Made one one time by substituting for the cat whisker and germanium crystal with a safety pin and a razor blade. Learned about that from reading what lots of GI's did in the field during WW!! days.

Gus :-)))

Nolen Hart (author) from Southwest on August 23, 2012:

At age 13 I built my first crystal radio kit. It led to a lifetime hobby and even helping with hurricane relief efforts in the Bahamas.

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