Monday, September 27, 2010

-- --- ·-· ··· · -·-· --- -·· ·

So for those who do not know, the title of my post this hour says "Morse Code" in, well, Morse Code.  Morse Code was the VERY FIRST digital mode of transmitting data across airwaves, which happened long before a microphone came along.

Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment. The International Morse Code encodes the Roman alphabet, the Arabic numerals and a small set of punctuation and procedural signals as standardized sequences of short and long "dots" and "dashes", or "dits" and "dahs". Because many non-English natural languages use more than the 26 Roman letters, extensions to the Morse alphabet exist for those languages.

Morse code speed is specified in words per minute (WPM) and associated with an "element time" equal to 1.2 seconds divided by the speed in WPM. A dot consists of an "on" element followed by an "off" element, and a dash is three "on" elements and one "off" element. Each character is a sequence of dots and dashes, with the shorter sequences assigned to the more frequently used letters in English – the letter 'E' represented by a single dot, and the letter 'T' by a single dash. A speed of 12 WPM is therefore associated with an element time of 100 milliseconds, so each dot is 100 ms long and each dash is 300 ms long, each followed by 100 ms of silence.

A related but different code was originally created for Samuel F. B. Morse's electric telegraph in the early 1840s. In the 1890s it began to be extensively used for early radio communication before it was possible to transmit voice. In the early part of the twentieth century, most high-speed international communication used Morse code on telegraph lines, undersea cables and radio circuits. However, on-off keying, variable character lengths, the limited character set and the lack of forward error correction are inefficient and poorly suited to computer reception, so machine-to-machine communication generally uses frequency shift keying (FSK) or phase shift keying (PSK) and encodes text in the Baudot, ASCII and Unicode character sets.

I've been spending a few minutes here and there over the course of five months attempting to learn Morse Code, or CW as its more widely known.  A little known to the internet fact about me, I'm an active licensed Amateur Radio operator that you could sometimes catch on HF radio frequencies mostly in the 14mhz range.  20 Meters as its known (for the 20 meter wavelength of 14MHz) is one of my favorite bands and typically what I operate both at home and mobile.  While I enjoy chatting it up on a local 145mhz FM repeater, most of my HF operation is normally a relaxed state during contests.  Never really got into "rag chewing" on HF.

The guy who really helped me along with the hobby got me obsessed with operating known as "QRP" or weak signal low power transmission and the common mode of operation on QRP is typically CW (Morse Code.)  This has been something I've wanted to learn for years just never was able to accomplish.  It wasn't until recently where I really stated to put some effort into it, just wish I could quit my job and dedicate my life to ham radio.  haha.  That'd be nice.  Much as I've put most of it off I'm actually starting to really learn a lot of the alphabet.  It seems like a daunting task, but I can copy many letters and a few words in the 30 words per minute range, and can even send a few misc things in excess of 40 words / minute.

Was just thinking that I'm getting frustrated that I don't have more time to dedicate to just learning the code and seems like its taking forever.  My "elmer" gave me some code recordings that put on my ipod in order to try and learn.  This has taught me the letters A, B, refined C, D, E, and F.  The recording starts with sending the letter at a slow speed then slow increases it.  Starts with A, A, A, A, A, A, A, A, then witches to B.  B, B, B, B, B, B, B, B.  At that point it starts sending ABBBABABABBABAAABABA at random with increasing speed.  Next it'll move to C, then D, then send C and D, etc.  Thing is they say to only spend 15 to 20 minutes a day on it or you'll burn yourself out but the problem is when I want to start reviewing my progress that'll typically end up burning that 15 to 20 minutes before I even start on new letters.

My overall progress is A, B, C, D, E, F, K, M, O, Q, R, S, T, and the Numerical Zero.  The neat thing about Morse digits is how they progress, unlike the alphabet.  1 is ·----, 2 is ··---, 3 ···--, 4 ····-, ·····, -····, --···, etc..  Those should be pretty easy to learn, as you notice there is one dit in 1, two dits in 2, and so forth. 

10 comments:

AdBrite

>