History of the telegraph
The first electrical equipment for telegraphic transmission were invented by American Samuel F. B. Morse in 1836, and the following year by the English physicist Charles Wheatstone in collaboration with the engineer Sir William F. Cooke. The basic code called Morse code messages transmitted by electrical impulses that flow through a single cable. The apparatus of Morse, who made the first public telegram in 1844, was shaped electric switch. By finger pressure, allowing the passage of current during a certain period and then cancel it. The original Morse receiver had a electromagnetically controlled pointer that drew lines on a paper tape on a revolving cylinder. The lines had a length dependent on the duration of the electrical current flowing through the wires of the electromagnet and had the appearance of dots and dashes.
Materials for this project (shown below) they can get from our kit Telegraph.
- Wood base
- Enameled copper wire
- La’mainas metal handle and buzzer
- Nails and screws
- Battery holder
1 .- The basis of the telegraph in this kit comes with a few pilot holes. Diagrams are used the image of the side to mark the holes with letters. This will help us in the next steps which need to connect the wires. The hole marked N is a hole that goes to the other side of the wood.
2 .- Insert the nail into the hole large N. The nail should not protrude from the back of the board. Then, install the Z-shaped buzzer, shall be 2mm on the nail. This nail will be the core of the electromagnet.
3 .- Wrap some tape over the nail. This film acts as an insulator and prevents the wire touch the nail. While the wire has a glaze (hence the name) use tape as an added precaution.
4 .- Take the spool of No. 28 AWG magnet wire. 12 cm is left as the start of the wire and then wrapped around the nail about 400 to 500 laps. Finally left at the end of another 12 cm. Cut the Alabre.
5 .- You can twist the ends of the enameled wire to prevent unwrapping. It wraps again or insulating tape to protect the wire. Now we take the enamel wire ends and using sandpaper to remove nail about 3 cm from the ends of magnet wire. With this we have a coil.
6 .- Insert a screw into the hole A.
7 .- Wrap and secure the wire into the bolt in position A. also connects the battery black wire of the same screw. The bare part of the battery wire should be below the screw head. Tighten the screw tightly.
8 .- Insert a screw into the hole C and connect the other end of the coil to the screw C.
9 .- We had a screw in the hole in the small metal plate and then go into the hole B, so the other end is on the screw C, without touching it.
10 .- At this point the circuit is ready, you can check by pressing installing batteries and can strip the screw C. Immediately the big nail must become a magnet.
11 .- Now install the Z-shaped buzzer placing a screw through the hole in one end and inserting into the hole Z. Place this strip of metal so that the longest part is over the nail, but without touching it. The distance between the nail head and the metal strip should be about 3 millimeters.
12 .- At this point the buzzer is ready for testing. Pressing the small strip of metal (now called manipulator) and the longest strip of metal to touch the nail head causing a click.
The photo opposite shows the complete telegraph, as well as parts of the kit of electromagnetism.
More than 10 projects in one kit
This kit of electromagnetism gives the unique opportunity to conduct over 10 experiments and projects related to electromagnetism. If you do not have the kit please order now.