Spring 2007 Issue

CW: An Important Mode on VHF

Just because Morse code has been eliminated from amateur radio testing does not mean
that it is no longer a useful means of communications. Here CQ VHF Features
Editor WB2AMU explains the important role that the code continues to play in many
VHF-plus communications opportunities.


By Ken Neubeck, WB2AMU

Here is the straight key that Ken, WB2AMU, uses when operating on 6 meters and the other VHF bands from his car during contests and also from his work location on Long Island, NY. It is used on a flat surface, such as the vehicle’s seat or on top of the dashboard, whereas a bug might be a little more difficult to use. Hence, simple is better for portable operations! (Photo by WB2AMU)

The recent change made by the FCC to eliminate code testing as a requirement for getting a ham radio license in the U.S. has created a lot of questions with regard to whether CW will continue to be used on the amateur radio bands as much as it has been. Will the change in the requirement affect those of us who primarily operate in the VHF range? I submit that the use of Morse code will not change for those of us devoted to VHF. I feel that the major changes due to the dropping of CW from amateur radio testing are going to be felt more on the HF bands than in the VHF range.

The reason for this is straightforward. Technician Class hams who did not learn the code were pretty much situated in the VHF range from 6 meters and up, using both FM and SSB modes. Other licensees who use the VHF bands are there because of personal interest in the unique characteristics of these bands.

As emphasized in several sections of my book Six Meters, A Guide to the Magic Band (Worldradio Books, 2003), CW remains a very important mode for those who are devoted to the VHF bands, particularly in the weak-signal area. Specifically, CW remains a major mode for many active VHF operators in three areas: aurora propagation, VHF contesting, and chasing DX on 6 meters.

During times of high geomagnetic activity, contacts via propagation by means of aurora backscatter become possible on the lower VHF bands of 6 and sometimes 2 meters. Because of the tremendous amount of auroral distortion on the radio signals, CW is the most effective means of communication. While voice communication is possible during a strong aurora opening on 6 meters, it is not nearly as effective if the aurora is capable of reflecting 2-meter signals. Essentially, the great majority of aurora backscatter communications made on 2 meters is via CW. This is because the signal is made so wide via the distortion that the voice mode is completely unintelligible on the 2-meter band. Thus, CW will still be important in this area of propagation.

In VHF contesting CW is still a very important mode. This is true for contesters such as myself who operate QRP and need to attract the attention of stations that are far away and are not able to hear my 10-watt SSB signal. CW provides an appreciable dB gain over SSB with the width of the signal as well as the simplicity of the signal. From my VHF QRP contesting experience, I estimate that roughly 10 to 20 percent of my contacts with stations during the three ARRL VHF contests in which I have participated have been completed using CW. I find it both surprising and pleasant that many SSB stations on the VHF bands are able to decipher CW. Thus, being a VHFer does not mean that you are not capable of using CW!

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