NAME

CW - the international Morse code

DESCRIPTION

CW is an abbreviation for "continuous wave", the commonly used technical term for Morse code communication. A basic knowledge or understanding of Morse code is a requirement for Radio Amateurs and Marine Radio Operators in many parts of the world.

MORSE CODE TIMINGS

In Morse code, a dot or dash is referred to as an element. The basic timing unit is the dot period. This is the time taken to send a dot, not including any space before or after the dot. The lengths of all other elements are then derived from this basic unit, using the following rules:

: The duration of a dash is three dots.
: The time between each element (dot or dash) is one dot length.
: The space between characters is three dot lengths.
: The space between words is seven dot lengths.

The following formula calculates the dot period in microseconds from the Morse code speed in words per minute:

dot period = ( 1200000 / speed )

This formula arises from the use of the word PARIS as a 'standard' word for calibrating Morse code speed. PARIS is 50 units long when sent in Morse code. Analysis of English plain-text indicates that the average word is 50 units, including spaces.

MORSE CODE CHARACTERS

The following list shows the IS0 8859-1 (Latin-1) characters that have commonly understood representations in Morse code:

: ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"$()+-./:;=?_@ and space

In addition, following ISO 8859-1 and ISO 8859-2 accented characters are also part of the generally accepted international Morse code:

: ÜÄÇÖÉÈÀÑ (S with cedilla), (Z with caron/hacek),

Finally, libcw adds the following ASCII characters as extensions to single character procedural signals:

: <>!&^~

MORSE CODE CHARACTER TABLES

The following table shows the Morse code equivalents for the ISO 8859-1, accented ISO 8859-1, and accented ISO 8859-2 characters above. The ASCII portion of this table is taken from the ARRL Handbook, and the accented extensions from various other sources:

Ch	Code	Ch	Code
A	.-	B	-...
C	-.-.	D	-..
E	.	F	..-.
G	--.	H	....
I	..	J	.---
K	-.-	L	.-..
M	--	N	-.
O	---	P	.--.
Q	--.-	R	.-.
S	...	T	-
U	..-	V	...-
W	.--	X	-..-
Y	-.--	Z	--..
0	-----	1	.----
2	..---	3	...--
4	....-	5	.....
6	-....	7	--...
8	---..	9	----.
"	.-..-.	'	.----.
$	...-..-	(	-.--.
)	-.--.-	+	.-.-.
,	--..--	-	-....-
.	.-.-.-	/	-..-.
:	---...	;	-.-.-.
=	-...-	?	..--..
_	..--.-

Ch	Code	Ch	Code
Ü	..--	Ä	.-.-
Ç	-.-..	Ö	---.
É	..-..	À	.-..-
À	.--.-	Ñ	--.--
(S+cedilla)	----	(Z+caron/hacek)	--..-

In addition to the above standard characters, the following characters are conventionally used for punctuation and procedural signals as follows:

Ch	Code	Ch	Code
"	.-..-.	'	.----.
$	...-..-	(	-.--.
)	-.--.-	+	.-.-.
,	--..--	-	-....-
.	.-.-.-	/	-..-.
:	---...	;	-.-.-.
=	-...-	?	..--..
_	..--.-	@	.--.-.

and the following are non-conventional extensions implemented by libcw:

Ch	Code	Ch	Code
<	...-.-	>	-...-.-
!	...-.	&	.-...
^	-.-.-	~	.-.-..

An alternative view of punctuation and procedural signals is as combination Morse characters:

Ch	Prosig	Ch	Prosig
"	[AF]	'	[WG]
$	[SX]	(	[KN]
)	[KK]	+	[AR]
,	[MIM]	-	[DU]
.	[AAA]	/	[DN]
:	[OS]	;	[KR]
=	[BT]	?	[IMI]
_	[IQ]	@	[AC]
<	[VA],[SK]	>	[BK]
!	[SN]	&	[AS]
^	[KA]	~	[AL]

NOTES