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Questions tagged [cw]

Continuous Wave (CW), or Morse code over audible tones. Use this tag for any question relating to Morse code.

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2answers
81 views

Why do CW signals get converted to pure sine wave tones at 750 Hz?

I've been reading about the history of telegraphy, and I knew that back then radio signals were produced in massive strength by using powerful dynamos and magnetos, with a telegraph key to interrupt ...
3
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1answer
87 views

Why were “PARIS” and “CODEX” considered “typical words”?

In the context of wondering how to convert characters per minute to words per minute, it was pointed out that CODEX and PARIS are used as typical words for measuring speed of CW operators. As the ...
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2answers
96 views

What is the purpose of the German CW exam if it is not required to use CW?

To receive the amateur radio license Klasse A (HAREC) in Germany it is since 2005 not required anymore to pass a CW exam, due to a corresponding change in the Radio Regulations. However, the exam is ...
13
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9answers
4k views

Is Morse code a digital, binary mode?

At first glance Morse code looks like a digital mode - there are dits and dahs, two values which contain the information of the transmission. Alternatively, at any point in time there either is a ...
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1answer
74 views

Is a US Extra class exam from the '90s valid to upgrade from Advanced class today?

If one passed the Extra written test in the late '90s at an ARRL test center but did not get the 20wpm endorsement, yet is an Advanced operator, would they now be upgraded to Extra class or do they ...
2
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1answer
140 views

Converting WPM to CPM

I'm using an Anroid app for learning CW. In Germany, it's common to define the speed in CPM ("characters per minute", or German BPM for "Buchstaben pro Minute). However, the Morse trainer I use ...
3
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1answer
542 views

Yaesu FT-450D CW from computer - DATA and CAT connectors

Yaesu FT-450D Transceiver USB-to-DB9 cable installed to the CAT interface Computer runs the ADMS-450 channel-programming program fine. Computer can run the PCC remote-control program fine. DATA ...
6
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2answers
122 views

Morse Code meta-command sequences?

When using Morse Code as an accessibility/disability communication or input method, are there any non-alphanumeric dot-dash sequences that are more common or more suitable for meta-commands, such as “...
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1answer
204 views

Morse code in a puzzle

I'm working on a morse code geocache puzzle. Firstly I had to listen to Morse code and I got the following words from it SYGYO UMPET KUSIK MUMWY MOPPE MACOP TUGNY WAAXT MUFAJ MIAMG TUGND I suspect ...
7
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2answers
120 views

Are there any rules/conventions for transmitting coordinates in CW?

I am wondering how hams transmit coordinates in Morse code. Considering that coordinates can be represented in many different formats (such as DD, DDM, DMS, WGS84, etc.) and that an error in the ...
4
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2answers
136 views

Has anyone actually heard or used rare Morse code characters on the air?

When I got my license about 50 years ago, I believe the only punctuation marks on the test were the period, comma, question mark, and slash mark. Once on the air, I heard and used the usual prosigns, ...
6
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3answers
220 views

How do I send negative numbers or below zero in CW?

Sometimes when operating CW I want to send numbers that are negative. In particular when operating outdoors during the winter and someone asks the temperature, I would like to come back in CW with -...
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3answers
404 views

What was the origin of the Morse code abbreviations “hi” and “es”?

In Morse code, hams use "hi" to indicate a laugh, and "es" to mean "and". Where did these abbreviations come from? Both being all dots, they are short and easy to send and easy to recognize, but why ...
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1answer
62 views

“;” in morse “-.-.-” or “-.-.-.”? [duplicate]

What is the correct sign for ";" in morse? FLdigi converts "-.-.-." to ";" whereas in various code lookup tables I see "-.-.-" Can both be used or is one of the morse codes valid?
11
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6answers
284 views

Key CW on zero crossings - zero bandwidth?

I remember being surprised to learn that a CW signal has a bandwidth (albeit small), but when I thought it over, it made sense. Essentially, we are modulating the carrier with a low frequency square ...
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1answer
173 views

How to transition CW ability to listening instead of simply copying - software assist?

I was recently reading this article from the ARRL web site, Morse Code at 140 WPM (ARRL) about Chuck Adams, K7QO, who claims to be able to handle this speed all by himself. Very interesting article....
3
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1answer
286 views

Difference between Iambic keyer modes?

What is the difference between Iambic Keyer mode A and mode B? Are there any other popular keyer modes? Why would one choose one mode over the other? If only one Iambic keyer mode is to be ...
2
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2answers
418 views

How to use a Linux computer as a paddle key code practice oscillator

I'm working on learning Morse code, and I'm looking for a way to use my computer as a practice oscillator with a double paddle key. I'm using a Linux PC, but a Raspberry Pi solution would be cool to. ...
3
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4answers
330 views

What's this maybe-morse-code “CQ CQ GE EDEN” and “DD” in Le Eden de la Grisaia?

The ending song of an anime television series called Le Eden de la Grisaia here has a light flashing. I suspect it may be Morse Code. By watching the video a little more slowly than usual (frame by ...
6
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3answers
627 views

How slow is slow telegraphy?

On the UK Band Plan there are frequencies stating “QRS (slow telegraphy) Centre of Activity”. For example, 14,055 kHz on 20m and 3,555 kHz on 80m. What is considered slow? (<15 wpm?) How close ...
4
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1answer
171 views

Where exactly is the Morse code character “;” defined?

I've seen that quite often in Morse code tables (for example here), under punctuation, a semicolon ";"character is listed. However, the ITU-R M.1677-1 doesn't specify that character as a part of ...
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4answers
555 views

Why do some straight keys have a slider that shorts the contacts continuously?

I ended up with an old straight key that has a curious feature: below the main arm that you would tap on, there's an extra metal flange that can sort of loosely pinch an extra sliding lever underneath,...
5
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4answers
1k views

Single or Dual Paddle Key?

I want to eventually use a CW paddle and built in keyer in my Yaesu FT-890. What are the merits of each style. Single or Dual Paddle. Does it make any difference if I start with say a dual paddle then ...
5
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2answers
124 views

Air gapped digital communications mode on VHF?

According to this question MCW (modulated continuous wave) is allowed on large portions of the VHF bands in the U.S. Is using MCW suitable for passing small amounts of digital data between 2 PCs or ...
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2answers
118 views

Morse code help

http://vocaroo.com/i/s0fsMOJ82A7k Trying to decipher this morse code if someone can help me. It's 14 characters long and the first lot is Illuminatih I think.
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2answers
358 views

Looking for a morse code decoder that simulates keyboard input

I know that there are several commercial programs that will decode incoming CW using the computer's sound card, but this is not quite what I need. The specific requirement that I have is to feed the ...
6
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5answers
2k views

Should I learn morse at “both” speeds?

There are many anecdotes of hams learning Morse Code at e.g. 5wpm and then "hitting a wall" trying to gradually speed up to 15wpm. David G. Finley, N1IRZ claims the reason is this: Morse at 5 wpm ...
2
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2answers
924 views

Is there a preferred order for learning Morse code using the Koch method?

The Koch method of learning Morse code is based on the idea that you learn characters at full speed, but a reduced set of characters that is expanded over time, instead of learning the full set of ...
2
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4answers
184 views

CW “training” recordings

I'd like to get some recordings of typical receiver audio output of HF CW transmissions. I'd like to both train my mental copying capabilities and look into improved automatic (software) CW ...
2
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3answers
534 views

Comms between Raspberry Pis over CW on 40m

I'm completely new to amateur radio, so please forgive me if this is a silly question. I'm looking at these devices: Assembled HAM RADIO 40M CW HF QRP Pixie Transmitter Receiver 7.023-7.026MHz DIY on ...
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0answers
59 views

Is it suitable to use DSSS in a narrow-band channel for a power-starved system

I want to build a system that can transmit data through 2-way radios as far as possible. I use the "line-in" as the input of the baseband signal in the transmitter and use the "audio out" as the ...
6
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3answers
843 views

What is the origin, history behind “Ben's Best Bent Wire”?

Bens Best Bent Wire My uncle, who was a Merchant Marine in WWII used to tell me this. He was a ham, and said it would develop my fist musically. I was a small child at the time, and through his ...
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6answers
507 views

Looking for a CW Tutor app [closed]

Is there an app that sends random morse code that I can copy to paper, then shows me what was sent for me to check my work? Basically an app that works like the MFJ-418 Code Tutor. All the apps I find ...
2
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1answer
403 views

Where can I find the definition of the Q Codes as they should be used in amateur radio (CW)?

Where can I find the definition of the Q Codes for amateur radio? So far I could only find ITU-R M.1172 ANNEX 1 Miscellaneous abbreviations and signals to be used for radiocommunications in ...
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1answer
143 views

CW paddle interface wiring problem

I have the MFJ-564B iambic paddle which I need to wire to the MFJ-552 CW interface. The paddle is stereo (dits/dahs) and the interface is mono (when connected to paddle, only gives DITS). How can I ...
0
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1answer
211 views

Testing my HB-1B QRP CW Transceiver on 40m

I'm a new ham and have only used 2m/70cm so far. I have recently completed a QRP CW setup: a YouKits HB-1B transceiver and a simple wire dipole. I haven't made any contacts yet, and I'm wodering if ...
2
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0answers
108 views

How can I connect a CW keyer to my Mac and transmit CW on VHF? [duplicate]

I currently have a Kenwood TM-V71A 2m/70cm transceiver that I would like to connect to my Macbook to transmit morse code, using the cocoaModem software. Aside from the cables needed to connect the ...
2
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1answer
1k views

Morse code for hash (#)

Is there a morse code for a hash character? If so, what is that morse code? My thoughts where that there is morse code for an @ but why not for a #?
2
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1answer
792 views

Do I need a Balun for a single band QRP antenna?

I have a little MFJ QRP CW 20m rig that I plan to turn into a portable kit for SOTA peaks. I have everything figured out except for the antenna. I am wanting to make a dipole. However, I was wondering,...
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2answers
1k views

How does selecting the opposite sideband when receiving CW on HF reduce interference?

I am studying for my FCC General Class license, and question/answer G4A02 reads as follows: Q: What is one advantage of selecting the opposite or "reverse" ...
5
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1answer
232 views

History and significance of term “lid”

What is the history on the term “lid” when referring to a telegrapher’s capability? How did it originate and what is the significance if any of each letter?
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2answers
2k views

Wiring a CW paddle

What kind of cable would be suitable for wiring an MFJ-564B Iambic CW Paddle to an Icom IC-718? I have heard that you can just use a length of old electric guitar cord but I was not sure what to do.
4
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1answer
211 views

Listening below the carrier frequency gives a weaker signal than above the carrier frequency - why?

I have a 20m CW transceiver with an option for a wide or a narrow filter. When the narrow filter is selected, a crystal ladder filter is used in the intermediate frequency filter, between two mixers. ...
5
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4answers
422 views

What if someone responds to my CQ, but I can't hear him?

I tried making a CQ on 20 m, 14.060 MHz (the QRP CQ frequency) and parallel to that I had a WebSDR on my computer just to keep an eye on the band. I saw someone responding on the WebSDR, which is ...
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4answers
1k views

Shaving Quartz Crystal for New Frequency

Back in the 1960s during my Novice days I operated on the 40-meter band only with 4 different quartz crystals that determined my transmitting frequency with my Eico 720 CW transmitter. I had heard ...
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3answers
746 views

CW contact content

I received my license and built and tested my first CW transceiver. I've spent the last weeks learning Morse code. Now, time has come to make the first contact. But what is a typical CW contact? When ...
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2answers
1k views

Do I really need a side-tone oscillator?

I'm throwing together bits-and-pieces towards my rig on a less than shoestring budget. It is possible to apply a take-off from the key and use it to drive a piezo-buzzer. Of course, there won't be any ...
2
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2answers
123 views

Terminology for written “CW-like” Code?

Morse Code is defined by most dictionaries in terms of sequences of short and long signals. What would be the most common or most descriptive terminology for un-timed written or printed code, where ...
2
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1answer
2k views

Decoding the Morse code

I am using a crystal to transmit morse codes, and I am using Kenwood radio receiver to obtain the signal. It receives the signal with a lot of noise, though we can figure out the morse code sound. I ...
5
votes
3answers
2k views

How are capital letters sent in Morse code?

There is only one alphabet in Morse code, so is there a recognised way to indicate a capital letter?