Nibbles and Bits
The Care and Feeding of My Pet Arduino


by Budd Churchward - WB7FHC - NIBBLES AND BITS LIBRARY


Morse Code Oscillator

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Section 1 - Building a Telegraph Key
This project and a couple others that follow will call for the use of a telegraph key. You can make due with the micro push button switches that we have used in other projects, but you will soon find that they are not very comfortable for practicing Morse Code. You might find telegraph keys for sale on eBay or perhaps you know of a Ham Radio operator who has one to spare.

We will show you, here, how you can build a simple key with parts you might find around home.

As you can see in the photo above, we are going to need a spring type clothes pin, two small bolts and four nuts. We will also need a block of wood to glue the key to.

We will use a drill and two small bits, a glue gun, and a couple pieces of hook up wire.

Start by gently pulling the clothes pin apart.

Place the two wooden pegs together back to back and drill a hole, the diameter of your bolts, through both of them at the same time so they line up together. Leave room for your finger tip between the holes and the end of the pegs. I didn't get mine centered too well. Hope you do better.
Attach nuts and bolts to both pegs and put the clothes pin back together again.

Notice in the photo that there are two nuts on the top half of the key, one on each side of the peg. There is only one nut on the bottom half. The fourth nut will be added later.

Drill a larger hole part way into the surface of your block of wood. It needs to be big enough and deep enough to allow the head of the bottom bolt to sit below the surface of the board when you glue the key down.
I used a glue gun to attach the clothes pin to my block of wood.
Here you see the key glued down.
Notice in this photo that I have added the fourth nut. It sits right on top of the other nut. We use the two of them to clamp down a piece of wire. Another piece of wire is added between the head of the top bolt and the nut right under it.
That completes the telegraph key that we will be using in several projects. In the next few sections we will wire it up to Arduino and write a short sketch that will allow you to start sending Morse Code.

Before you run off, click: to see a short video of this key in operation.

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