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22

One of the biggest advantages of CW is that users worldwide can contact each other without knowing English, or any specific language. Conversation is limited to the common Q codes, but these provide significant flexibility and ability to communicate making Morse Code a common language of sorts.


21

According to Shannon (in A Mathematical Theory of Communication - and who's going to argue with Shannon?) there are really only four symbols in Morse, not five: "dit" (defined as one unit time on followed by one unit time off) "dah" (three unit times on followed by one unit time off) "letter space" (two unit times off) (should follow a dit or dah symbol) "...


19

CW signals are not “transmitted on the upper sideband”, nor the lower one. A CW signal is approximately at a single frequency (with only the additional bandwidth required to allow the key-up and key-down transitions). However, the standard method of receiving a CW signal is identical in structure to a single-sideband receiver. The local oscillator (LO) of ...


19

My understanding is that in at least some telegraph systems, the principle of operation was as in this circuit (where the coils depicted are actually telegraph sounders): simulate this circuit – Schematic created using CircuitLab Thus, your key's shorting switch is, in radio terms, your transmit/receive switch: you close it in order to listen, and ...


15

20 wpm. §97-119: (b) The call sign must be transmitted with an emission authorized for the transmitting channel in one of the following ways: (1) By a CW emission. When keyed by an automatic device used only for identification, the speed must not exceed 20 words per minute;


12

Many Morse abbreviations and conventions come from before the days of radio, and we are relative latecomers to the game compared to the telegraphy guys. For this question, I found an old reference here from a 1920 Morse Telegraphy manual where the ES abbreviation is shown in the old American code as being the code for the ampersand character &. It is ...


12

Generally, QSL means "I acknowledge receipt". "QSL?" (with a question mark) means "please acknowledge". Sometimes when listening to QSOs you will hear someone say QSL VIA BURO or QSL DIRECT or similar, and those are instructions on how to send a QSL card. But QSL on its own just means "acknowledged". Finally, if someone says PSE QSL then that usually ...


11

Because it's fun to send and receive messages by Morse code! It's something that can be done without any specialized equipment for sending and receiving. It's a shared historic experience. It's a challenge, and a skill that is fun to learn. It puts you into a special "club," setting you apart from those non-CW capable hams. But mostly, it's just fun.


11

In the simplest form, CW consists of a pure sine wave multiplied with a square wave that's either 0 or 1, corresponding to the keying of the carrier. As with a mixer, or amplitude modulation, multiplying two signals generates frequency components that are the sum and difference of each frequency component of the multiplicands. In our simple form above, ...


11

Try to find the allocated amateur radio band plans for your country. You will notice that there are reserved sections of the band plan that are for CW only. Usually they are in the first few kHz (i.e. lowest frequency) for the band you're interested in. For instance, in Australia the CW portions for common HF bands are: band ~freq CW portion 160m 1.8MHz ...


11

Since you're simulating the situation with non-transmitting equipment, you get the play the part of actual emergency agencies. You'd start by asking the SOS caller to identify themselves (call sign, ship name, etc.) and give their location and the nature of the emergency. Of course, unless your 5 year old knows a lot more Morse than just SOS, that's where ...


11

That is Morse code, in Norwegian, being sent with a "bug" (Vibroplex type mechanical key). The two operators are LA6UH and LA7JS. Probably not something you want to figure out how to decode with a machine, but the ops' "fists" make them very recognizable to those who know them. LA6UH gives a clue in his bio, where he writes: I spent a couple of years of ...


10

I love Morse code for these reasons: It's fun. There is something satisfying about pulling a really weak signal out from the noise just 10s of Hz away from another really strong semi-local signal, and making a decent contact with someone halfway around the planet with less than 100W. I can put headphones on and operate in the living room while the XYL is ...


10

Data from the Reverse Beacon Network provides an answer. RBN receivers and computers decode CW (and other "digital" modes) to identify stations calling CQ and posts information about signal strength and operating speed. I think it's reasonable to assume that QSOs are conducted at the same speed as the op sends "CQ." Click on "DX Spots" followed by "Download ...


10

In the International Code of Signals (an International system of maritime communication, including radiotelegraphy), AAA (over-bar) is designated for both full stop and for decimal point. (See flashing light procedure signaling, page 20.)


10

First, some history. As I understand it, the "dit-dit" (E E) comes from an old practice. There is a short tune in popular music that was often used to end a musical performance in a humorous way, called "shave and a haircut, two bits". The Wikipedia article has a recording of the tune. For older people, the rhythm of the notes in the tune is instantly ...


9

I am a new ham, and I decided to learn it, and use it, strictly for the purpose of efficiency. CW operation is low bandwidth, and therefore requires very little power to get a signal out over long distances. You will not get the same results from voice transmissions or other larger bandwidth data modes (although JT-65A and PSK31 are relatively efficient data ...


9

Morse code requires an extremely small bandwidth (and is usable in a channel that has a relatively low S/N) for a mode that requires no digital processing hardware or computer/digital logic chips (instead requiring just the skill of a couple of human brains) to communicate. Some people value accomplishing things using personally learned skills rather than ...


9

I would echo the point mentioned by N8WRL: "Why do I operate CW? It is a blast!" I'm actually re-learning morse and realising I've been missing out on a lot of fun over the years. In terms of learning and training, it feels some way between learning a musical instrument and learning a new language. It is an excellent way to stimulate the brain - an ...


9

I got my technician license in 1992 to play with packet and TCP/IP on VHF/UHF. I got bitten by the HF bug listening to the CW subbands. I decided to learn CW on my laptop on business trips. I struggled to pass 5 WPM for my Tech-plus but I did and I got on 80m CW. A few months later I had WAS and It wasn't long after that I passed 20 WPM for my Extra. Why do ...


9

There are. Wikipedia has a list: A little searching will turn up more. They don't always agree, since they are conventional extensions, not standards. Usage is sporadic at best. Many languages have mechanisms to cram their orthography into 7-bit ASCII, driven by the need for their language to work on computers.1 For example in German, "ß" can be written as ...


9

According to Coherent CW ... "The More You Know About a Signal, the Easier it is to Copy" by Peter Eaton, WB9FLW and George Heron, N2APB: Coherent software has several other convenient features in addition to auto-tune. It has a fine tuning aid that measures the incoming 800 Hz audio signal (with 0.1 Hz resolution!), and a frame-phasing tracking loop that ...


9

There isn't one. Why? Because it's not defined in the standard. "#" isn't the only symbol in common computer use which is not defined in Morse code. For example, Morse code can't distinguish upper and lower case letters. Nor does it have codes for any of {*^&_. The reason is likely that Morse code is intended to be memorized and decoded by a human, and ...


9

Single-lever paddles have a single lever that generates dots when pressed to one side, and dashes when pressed to the other. Dual-lever paddles have two paddles, one of which generates dots and the other generates dashes; when connected to a keyer in iambic mode with both levers pressed, a dual-lever paddle generates a stream of alternating dots and dashes. ...


9

QRP only means low power, often 1W or less. While you could technically have a 1W SSB transceiver and call it QRP, the practical range of such a radio would be limited. It is much easier to hear a single tone over the noise than it is to hear a voice which has its energy spread over a wide range of frequencies. Thus we say CW is a more sensitive mode: it ...


8

Since we are talking about the United States, the "phone" portions of each band are actually described as phone, CW & image. So it's not only legal, but it's perfectly acceptable to operate CW in that portion of the band. Contest rules generally confine contesters to the CW-only portion of the band making the rest of the band a viable option during CW ...


8

A really easy way to do this is to take an old USB mouse (or even a new cheap one) and solder the key across the left mouse button. You can then use key directly as mouse button input on most computers and Android phones (with an OTG cable) and use with Morse software or websites expecting mouse input e.g. :- http://morsecode.me http://www.web-adventures....


8

Land line telegraph keys are fitted with a circuit closer switch. Radio telegraph keys were not but many radio operators used land line keys because they were so readily available. This includes the rather ubiquitous J-38 about which more will be found below. The arcing that occurred at the key contacts of the early spark radios caused radio stations to ...


8

Especially true in a contest, or noisy environment: Hearing a "QSL?" from someone can mean they want to know specifically if what they've sent to you has been sent correctly. They may have been trying to pull your callsign out of the QRN or QRM and want to ONLY hear back from you a "QSL" or "R" so they can confidently log your call. If you hear correct ...


7

It was all I could afford when I was a kid. AM and SSB gear was expensive and still is! Stuck with it because: Signals are stronger, More of a challenge, and a CQ gets answered faster. Great people on CW.


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