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Flashlight Morse Code

Use light to communicate a special message to a friend. Grab a flashlight and head into the dark to send your secret in Morse code.

Flashlight Morse Code

Materials

Two flashlights
A friend
Morse code alphabet for each friend
Paper for each friend
A pencil for each friend
Darkness

Instructions

With your friend, learn how to use the Morse code alphabet with light.
1. It is made up of dots and dashes.
2. When using light, dots are transmitted by a quick flash of light.
3. Dashes are transmitted by a flash of light that is about three times as long as a dot flash.
4. After each letter, you should pause for about the length of a dash.
5. After each word, you should pause about the length of two dashes.
Practice using Morse code with light by making simple words. It can be tricky!
When you are ready, sit across from your friend in a dark room or yard. Make sure that each of you has a paper, pencil, flashlight, and the Morse code alphabet.
Try sending a question to your friend using flashlight Morse code.
As you transmit each letter, your friend should write it down on the paper so they can read your message.
When you are finished, wait for your friend to respond.
As they transmit each letter to you, write it down on the paper, just as they did. Once all the letters are sent, you’ll be able to read your friend’s response.

Flashlight Morse Code

Why is this a great thing to do?

Expands the idea of communication.

Encourages teamwork.

Promotes bonding between friends.

Talk About

“What problems did you encounter when you tried using flashlight Morse code? How can those problems be solved?”

“What is a benefit of being able to communicate with light?”

“Can you think of certain occasions when it might be handy to know how to send and receive Morse code with light?”

Tips & Extensions

It may be helpful for beginners to write out the series of dots and dashes before they start. As they begin to remember the patterns for each letter, they will better be able to translate words directly into code without this step.

If turning a flashlight on and off repeatedly is cumbersome, use a piece of cardboard or another opaque object to block the light at its source.

Morse code can also be transmitted with sound. Dots are short blips of sound, while dashes are slightly longer blips. Try using a piano or other instrument to transmit a Morse code message using sound.

Can you send a Morse code message by squeezing your friend’s hand or tapping their leg? Use a quick squeeze or tap for a dot and a longer one for a dash.

Make STEM Connections

Help your child develop a more in-depth understanding of how light can be used to communicate.

Catch fireflies.

Fireflies are flying beetles that use light to communicate. They use their light with each other to find mates, and their light also serves as a warning to predators that they do not taste good. Gently catch a firefly and watch it light up. What do you think it is trying to tell you?

Tour a lighthouse.

Lighthouses are tall buildings on the coast that use light to guide ships safely near shore. Lighthouses are also used to help sailors with navigation. Most lighthouses today are run electronically, but many years ago a lightkeeper was responsible for sending short codes to ships using light. Why do you think this is important?

Check out an emergency vehicle.

Fire trucks, ambulances, and police cars are all emergency vehicles. Their purpose is to help people as soon as possible. The lights on top of the vehicles communicate with other drivers by telling them to get out of the way quickly. Take an up-close look at an emergency vehicle. What color are the lights? Why?

Next Generation Science Standards (NGSS) Correlation

1-PS4-4

Use tools and materials to design and build a device that uses light or sound to solve the problem of communicating over a distance.