In this world, Morse code is still alive and well, though it is not necessary to learn it to get a license. For quite a while I thought that CW was quite an odd name for a way to transmit Morse code. Well, the deal is that before we had continuous waves, we already had Morse code on the radio, transmitted with a different kind of radio wave: the Damped Wave.
A Continuous Wave is a sinusoidal wave with a precise frequency. So radio stations used a different mechanism to produce a different kind of radio waves. In Morse Code a dot. It is said that a dash - unit is three time longer than a dot.
The Morse Code in fact consists of combinations of aurally distinguishable tones. A tone produced for short duration is a dot tone and a tone three times longer than this tone is a dash tone. It is advisable not to start practice sending the Morse code until the novice is proficient in receiving Morse code. Morse code practice cassettes and multimedia computer software are nowadays available. Mere gaining confidence in sending does not qualify you to be an expert receiver! In fact you may not be able to receive a single letter in Morse code even if you gained a sending proficiency of 12 words Per Minute WPM!
Remembering the Morse codes is an art by itself. It involves a rhythmic response in your mind. Try to remember the combination of dot. For this purpose, a dot. The space between two letters or characters is equal to three dot units. The space between two words is equal to five dot units. The minimum speed to qualify for a Grade II licence is 5 words per minute 5 wpm. A message containing letters when sent in 5 minutes or when received in 5 minutes makes your speed 5 wpm.
In fact Morse code devised by Samuel F. Morse is a primitive type of digital communication which still works efficiently in this era of microprocessors and computers. The Morse code itself consisted of two elements: a dot and a dash, and the various letters, numbers and other characters were made up by combining these two elements in different combinations.
By definition a dot is one unit long, and a dash is three units long. Spaces between adjacent dots and dashes are one unit long, the gap between letters is three units long, and between words it is seven.
Often the dot, was represented by the word "di" and the dash by "dah" tending to represent the sound more easily. Essentially CW refers to a Morse transmission using a radio signal - the abbreviation coming from the fact that it uses a Carrier Wave, or Continuous Wave that is interrupted.
There is no modulation apart from the breaks caused by the Morse characters. In this way, CW can be used to denote a simple Morse transmission that interrupts the carrier to give the required Morse characters. Although interrupted audio tones can be used to modulate a signal, this would not strictly be noted as CW. There is a huge variety of Morse keys that can be used for sending Morse code.
Not only are the shapes and sizes of the basic or straight Morse keys different, but there are also mechanical and electronic keys or Morse keyers available that make sending much easier and faster. Straight Morse key: The straight Morse key is the traditional form of Morse key that has a lever and uses an up and down motion to make and break the contact and hence make the dots and dashes.
It was also the first type of Morse key to be used. Mechanical semi-automatic keyer: The semi-automatic Morse key was developed to overcome an injury known as telegraph hand, but today we would know as repetitive strain injury, RSI. The key had a paddles and when moved to the left made contact for the dashes, and when moved to the right, it set a vibrating arm in motion to create the dots. Although it took a little time to learn, it reduced the instances of telegraph hand and enabled much faster operation.
One of the first keys of this type to be made was the Vibroplex, and these can still be obtained to this day. Electronic keyer: The electronic keyer is an electronic development of the mechanical key. The basic version has a paddle which creates a series of dashes when moved to the left, and dots when moved to the right. More advanced keyers have two paddles next to each other to provide a "squeeze" function where alternate dots and dashes are produced.
These were first known as squeeze keyers but today they are generally known as iambic keyers. Although full electronic keyers are available, most modern ham radio transceivers have the keyer electronics contained within the transceiver and only the paddle is required. This simplfies their installation and enables fast two way radio communications using Morse code. These are the main types of Morse key that are in use.
Computer technology is also widely used, ad using the right software, messages can be types in on a keyboard and the resulting Morse code is generated. Some software can also read Morse code, but often this is not as good as the human ear at decoding the message int he presence of interference.
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