On February 23, 2007, the FCC eliminated the Morse code requirement for all U.S.-issued amateur licenses. Within 72 hours of the announcement, the American Radio Relay League (ARRL) staff reported a doubling of the requests for study materials for new or upgraded licensees. Prospective licensees now had one less hurdle between them and a ham ticket.
Yet, there seems to be a recent resurgence in CW (Morse code) operation. Why? Morse code gets through when SSB fails. This isn’t just the die-hard CW fans speaking. It is a well-known fact. Hams around the world work rare countries every day using CW and power levels ranging from QRP to 100 watts with simple antennas. Portable operations like SOTA and POTA welcome the weight reduction as a result of small but feature-rich CW radios, lithium batteries, and truly portable antennas.
Our local club recently did a ham radio demonstration for several STEM classes. Their favorite topic was Morse code—hard to believe until we heard them plotting ways to use CW so they could pass messages secretly under the noses of teachers and administrators.
Supply chain shortages affect gasoline, baby formula, and computer chips. Ham radio also experiences shortages—primarily Field Day CW operators. Band captains are going crazy trying to recruit experienced CW ops. It seems there’s not enough talent available to copy pileups or send CW exchanges like “7A Ohio.” Predictably, phone and digital sections of the bands will likely be more crowded this year.
Tune In
Ready to give it a try? First, understand that learning Morse code is not hard. However, it takes diligent practice to become proficient. Think of it as learning to play the piano but without taking years to become an effective operator.
You’re going to have to actually listen to Morse code if you ever want to learn it. Being able to tune in CW signals correctly is a critical skill—a good starting point for those ready to tackle what’s needed to become a CW op. Turn on your transceiver and switch to one of the active ham bands. Move to the lower portion of the band where the CW signals are (for example, on 40 meters you’d tune between 7000 and 7125 KHz).
Switch the mode to CW and practice tuning in stations. Seek out one of the CW signals, tune in as close as you can—some radios match your frequency to the other station’s frequency using the spot or auto tune button. If necessary, activate the RIT (Receiver Incremental Tuning) to fine tune the station as you listen to the QSO. Make filter and bandwidth adjustments as necessary to help block interference. Some radios have adjustable speed settings in WPM, which matches the speed of the message being sent and enhances the ability to decode CW.
Electronic Assist
Charts, cheat sheets, and quick memorization schemes can actually slow you down. A decoder may help you sort out those beeping noises and actually get you to listen and connect code to letters, numbers, and eventually words and phrases. There are three main types: hardware decoders which are often paired with keyers; decoders built into some transceivers; and software programs that work with your radio and computer.
SOTAbeams WOLF-100 WOLFWAVE Advanced Audio Processor: Works with any radio using the speaker or headphone jack from your radio. It has bandpass filtering, noise reduction, age-related hearing correction, and a Morse decoder that can decode signals from 1 to 100 WPM. Add to this a CW regenerator that works on the CW signal in the center of the passband. It detects the signal and regenerates the CW with a clean sine-wave, making audio copy easier and cleaning up the background noise for improved accuracy. It also adjusts to received CW speed.
MFJ-461: Place the pocket-size portable MFJ Morse Code/CW Reader near your receiver’s speaker—then watch Morse code turn into text messages as they scroll across a 32-character LCD display. AutoTrak automatically locks on and tracks CW speed to decode high- and low-speed Morse code. A serial port lets you display CW text on a monitor using a computer and terminal program. When it’s too noisy for its internal microphone pickup, you can connect the MFJ-461 to your receiver with a cable.
Using Your Radio as Decoder
If your radio has a built-in CW decoder, follow the operation directions in your transceiver manual. Also note that some transceivers can utilize computer software to expand the display. On the Kenwood TS-590SG, received Morse code is shown in the front display, with 13 characters visible at a time as they scroll by. If you utilize the ARCP-590G control software, characters are shown in a dedicated window on the computer display.
Starting with the K3, Elecraft has used a similar slice of the panel display on their transceivers—even the KX2 and KX3 have this option. You’ll probably want to turn on CWT as a tuning aid. Also, auto-spot can be used to tune in signals.
Your success will often depend on receiver settings. Be sure to adjust the noise floor down to improve the S/N ratio. Also set your CW speed close to how fast you think the other station is sending to you. It doesn’t have to be exact, but within a few WPM. The Yaesu FTDX10 has a reasonably large decode screen, six lines of 40 characters each. There’s also a handy tuning offset indicator below the S-meter to help you precisely match the other station’s frequency.
Software Solutions
Fldigi is a popular modem program for most of the digital modes such as CW, PSK, MFSK, RTTY, Hell, DominoEX, Olivia, and Throb. Its appeal is in the number of digital modes it covers, including CW. Make sure you are using the radio in CW mode and not SSB. This will let you use your radio’s filtering capabilities. (Linux/ Mac/ Windows)
MRP40 decodes received CW audio that’s been fed to your computer’s sound card. The decoded text is then displayed on the computer’s monitor. MRP40 sends and reads CW (5 to 60 WPM), and helps to decode weak DX signals. The Audio Analyzer FFT Display displays the incoming Morse audio spectrum graphically, giving you a full overview of any CW activity in the selected audio band. MRP40 is compatible with Winkeyer USB, SignaLink USB Digital Communications Interface, Microham, and other popular interfaces. (Windows/Mac)
CwGet is a Morse decoder program with built-in options for large type and high contrast colors. No special hardware is required—you can use a single cable to connect the speaker output from a receiver to a computer with a sound card. It translates incoming Morse code into text using the font and colors of your choice, locks onto a signal (AFC), and automatically adjusts to the speed of a CW signal. CwGet does not transmit, but there is a companion program, CwType, that will. (Windows)
Tips for Using Decoders
CW decoders aren’t magic. Understand that they have limitations:
- Accurate decoding doesn’t happen with fading and poor reception conditions.
- There is a lot of sloppy code on the air—don’t expect readers to do the impossible when it comes to copying Morse code.
- Irregular rhythm, speed, and bad spacing affect accurate copy.
- Nothing can copy a weak signal with lots of noise.
- Make sure the signal is tuned as close as possible—use spot or auto tune. Signals way off frequency will not decode well.
- Use filtering to improve copy.
- Reduce the noise floor with RF gain control or attenuator.
- Invalid characters are displayed as block characters, spaces, or the letter E—usually a result of weak signals.
- With continued practice, it’s easier to fill in the blanks/missing characters.
Copying strong, well-sent code, especially messages sent with electronic keyers or keyboards, will always produce the best results. Tune into a W1AW code practice session sometime and see for yourself.
The ultimate CW decoder will always be the human brain, but software/firmware can also do a pretty good job helping you become more proficient. May the Morse be with you . . .
