Featured: Cheap Yet Fun Telegraph





Introduction: Featured: Cheap Yet Fun Telegraph

In this instructable, I will show you how to make a cheap AM telegraph out of things around the house. Depending on how many 9 volt batteries you hook up to it, you will get a diferent range. WARNING, ELECTRICITY IS VERY DANGEROUS!!! DO NOT plug into a wall socket or use a car battery, in doing so may result in serious INJURY or even DEATH! So only use 9 volt batteries and no more than 2. Lets get started!

Step 1: Gather the Matierials!

1small, flat block of wood. 9 volt batteries. assorted pieces of wood 1",2" & 3" in diamiter. paneling nails. wire coat hangers with no plactic coating. some leather gloves from doller general to protect those fingers. 1 hammer. And lots of will power!

Step 2: Time to Assemble.

Take the flat block of wood and lay it on a hard, flat surface. Now take the nails and the 9 volt battery. Lay the battery on a part of the board and put nails around the battery to hold it in place. Be sure not to nail through the battery. If done correctly, you should be able to turn the whole board upside down and the battery still be attached.

Now take a nail and hammer it about one inch away from the end of the + terminal on the battery. Wrap a small piece of wire on the last nail that you put in and when you are done coiling, leave enough wire to reach the + battery terminal. For the key, (thats the thing that you press down) you can use a paper clip or a small socket wrench. Nail that down so you can press one end and let go, it will return to its previous position. You can also use a spring from a pen. take a piece of wire and attach one end to the spool and the other to the key. Almost done!

Put a nail under the end of the key so that when you push down on the key, it will touch the nail. Put one nail touching the - terminal on the battery. take one more piece of wire and run it from the - terminal nail to the nail under the key and your ready!!!

Step 3: How It Works

The spool acts as an antenna, and when you press down the key, an electric spark is created which can be heard over an AM radio. The more batteries you add, the bigger the spark, the longer the range. Thank you for reading. see you soon!

Step 4: Warnings.

A quote from A comment below says that the system that I built will cause interference across A wide spectrum. This is true. Be warned not to make this thing to powerful, you most likely don't want to bother the neighbors next door. Making this may be illegal in your country.



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    I know this could be a fun project and your description is well done.
    However there are serious problems that anyone building it should consider.
    The first is that in most countries the use of 'spark transmission' is illegal and carries penalties.
    The second is that the system described would generate interference across a wide spectrum, thus causing annoyance to anyone in range trying to listen to the radio.
    I am not trying to spoil anyone's fun but I thought it worth mentioning before anyone suffers the consequences of building it.

    i gonna annoy the heck out of everybody in my neighborhood
    with my spark gap telegraph
    how should make telegraph without spark gap???
    plz help me

    You could just make the "Switching circuit", the telegraph key, and connect it to a computer via serial port. There are countless tutorials online how to do this so a few searches should lead you with some good results.

    Unfortunately, there is no 'simple' answer to your question. The fact remains that the use of spark gap methods would generate interference that will get reported and would lead to hefty fines. This is certainly true in the UK and the USA.
    Of course, you could be miles from anywhere and decide to 'risk' it but that would not be a sensible thing to do.
    If you are interested in pursuing legal (and more efficient) methods then you only need to search the web for lots of good advice and help. Another good way to get involved would be to seek out a local Ham Radio enthusiast or join an amateur radio society.
    I hope this helps.

    too bad, i am 13 years old boy who can't afford the price of the ham radio

    get a license of ham radio, and do it on 144 mhz

    This looks great.

    Thank you for your concern. by only using one or two 9 volt batteries, though you could only get a range of about 5-15 feet. there was no harm intended. but thank you again.