CW

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Carrier Wave (aka morse code, aka continuous wave) or CW is the first digital mode used in radio.

The ITU has dropped Morse code as a requirement for amateur radio licensing. Many countries have followed suite. Recently (January 2007), the FCC has dropped the testing requirement for CW for all license types within the US.

It is a very popular mode for contesting. Contests that support more than one mode will often support CW and generally score CW contacts at a higher rate than the phone modes.

The human brain has a remarkable ability to pick CW out of a very noisy environment. Only the modern digital methods seem able to compete with the human brain's ability to read an signal in the noise floor. Personally, even while learning CW I have been able to pick exchanges from noise so bad that I was listening to actual changes in the noise volume to read the signal. In my case, I was not able to read the whole exchange as I did not know enough code to hear it all, but the few letters and numbers I did know, I could hear in the noise (and spotting let me know who was actually in that noise as a double check).

Contents

Articles about CW

CW learning aides

Training for CW

In my experience (limited though it is) and from all that I have read and heard, you want to learn CW at a speed fast enough that you do not actually hear the dits and dahs but only hear the actual letter as a single sound. You also want to learn the code at a speed fast enough (spacing of letters and words) such that you do not replay the sound in your head. The goal is to hear the sound and think the letter immediately. At the highest speeds you will no longer even hear the individual letters, you will hear entire words.

If you start out thinking dits and dahs you will hit an early plateau in your speed that is probably less than 12 wpm. If you replay the sounds in your head you probably plateau around 20 wpm. If you hear the individual letters you probably plateau around 35-40 wpm. This is fast enough for most contesting. To get beyond 40 wpm will probably require you to hear entire words as a unique sound pattern.

Personally, for me I have found that I need to learn the code at a 30 wpm letter rate with a letter and word spacing greater than 25 wpm. One thing to note is that I type about 35 wpm and my practice sessions are with programs that allow me to type directly and get graded. If you use these programs you may find that you have to space out the words (but maybe not the letters) so that you have time to find the keys on the keyboard. Of course you can learn typing and the code at the same time.

One alternative to typing is to just listen and let the program display the codes. Supposedly, you will know when you are correct often enough if you use the Koch Method to learn. Personally, I prefer typing but I learned to type over 30 years ago and it is part of my life as I work daily with computers. YMMV

Koch Method

The "Koch Method" is an approach to rapidly learning CW. The general concepts of this method can be used in a lot of memorization tasks (multiplication tables, state capitals etc).

In simple steps the Koch Method for CW is:

  1. Select two characters (letters, numbers, symbols or pro-signs) to start
  2. Send random length groups 3-5 characters of random selection of current character set (2 at the start more latter)
  3. Check actual read vs. sent. If <90% accurate repeat step 2.
  4. If more characters to learn, add another character and repeat step 2.
  5. You are done.

You can combine Farnsworth and Koch Methods. That is, you can send letters with 12 wpm spacign but at a 20 wpm letter speed.


Need references to Koch Method.

Farnsworth

Keyers

  • K1EL (I own a Winkeyer2-USB that I still have to build)
  • AEA Morse Machines (I own an AEA-3 that I need to repair)

Keyer Interfaces

  • Rigblaster
  • Build your Own for a serial or parallel port (This is really easy, cable, two connectors, 2N2222 and 1K resistor)

Software Decoders

Some loggers like Write-log have built-in decoders. Some decoders cost money (I have no experience with the $$$ decoders). Some decoders are free.

Free Decoders

  • cwget
  • XPdecode (??? is this the right name --- note I need to get correct name here)
  • DM780 (Part of Ham Radio Deluxe) - Personal favorite

$$$ Decoders

Personal tools