Simple Telegraph Key and Sounder




About: I am Kaptain Kool, Zombie Slayer, Covenent Crusher, and Creator of Awesomeness. I love building anything out of metal, wood, and trash. I build for fun and occasionally out of necessity.

A while ago I built a telegraph machine and was amazed by the simplicity and the joy obtained from pounding out my name hundreds of times.  When I saw that the weekly challenge was magnet themed, I knew that I had to make an instructable.  I was able to build it in an hour while taking pictures, and I bet it could be done in about 30 minutes.  Telegraphs are simple communication devices using a switch operated at one station to control a electromagnet at a separate  telegraph station.  The electromagnet then will pull down a piece of steel for a short time or a longer time (dot or dash).  It was used in the U.S. civil war and as used as a major communication device from the early 1800's until the mid 1900's.  Now let's go make one!

Step 1: Materials

These Items can be found in any workshop or hardware store and are pretty basic:

Scrap wood (Plywood and a board about 3 inches high)
A nail a little taller than your board of wood 
Some sheet steel (thin)
Copper sheet 
Bottle cap
Insulated or magnet wire
9v battery and holder
assorted nails and screws


Saw (If you need to cut the wood)

Step 2: Wooden Bases

The base for the sounder is a piece of plywood attached to the 3 inch (or so) wooden board.  The Board should be a bit shorter than the nail that you are using for the electromagnet.   The base for the key is just a small piece of plywood.

Step 3: Making the Key

To make the key drill a hole through your bottle cap, piece of copper, and into your wooden base.  Then, put the screw through the copper, then the bottle cap, and lastly into the wood.  To finish your key put a nail in your base where the end of your copper piece so that they hit when you press on the copper.

Step 4: Electromagnet

Take your nail and wrap about 10-20 feet of insulated or magnet wire around it.  If you have a thicker piece of steel you will need to wrap more wire around the nail.  The more wire, the more strength the magnet will have.  If your telegraph doesn't work at first, I would try making your magnet stronger. 

Step 5: Make the Sounder

Attache the nail to your sounder base with your hammer.  Then take a thin piece of steel ( from a cookie or popcorn tin) and nail that to the top so that it hangs over the edge and above the electromagnet.  You want your piece of steel about a mm away from the electromagnet so that it will be able to bring the steel down.  This will take a lot of bending to get it just right, but it is necessary.

Step 6: Wire It Up

Now you have to wire it up, you can make the wires as long as you want up to a couple hundred feet.  Any longer than that and you will have to have batteries at regular intervals along the wires.  

Wire it like this:
Electromagnet to screw holding the copper to the bottle cap
Nail on key to battery holder +
Battery holder - to electromagnet

Now you're done! Look up Morse code and then pound out your name in dots and dashes for hours. If you haven't already figured it out, press the copper piece down until it comes in contact with the nail.  This should result in the electromagnet attaching to the piece of steel.

4th Epilog Challenge

Participated in the
4th Epilog Challenge

Summer Camping Challenge

Participated in the
Summer Camping Challenge



    • Pets Challenge

      Pets Challenge
    • Beauty Tips Contest

      Beauty Tips Contest
    • 1 Hour Challenge

      1 Hour Challenge

    23 Discussions


    6 years ago on Introduction

    fact is simple, but not obvious on the cord, hold the table view does not lead to gross fixed on the material.


    7 years ago on Introduction

    Nice telegrapher. If you take away the copper from the magnet it will be wireless.
    But then you have to Found it's Frequency... Its a hard work.

    12 replies

    If you take away the wire from the electromagnet then you will have no electromagnet and the whole project would be a failure.


    Left the wire on the electromagnet and left the copper on the switch but you take away the copper from the electromagnet (it is on the top of it)