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Weak Signal Communications Software Everywhere on HF

weak signal communications software

Sometimes, all you can see on the ham bands are weak signal communications software exchanges chugging away. Are these robots or real people? 

Anyone who listens to the ham bands these days should know that weak signal communications software has taken over. Your most popular choice is WSJT-X which implements most of the important modes. These include FT8, JT9 and WSPR. Using these digital modes, hams can achieve amazing contacts with low power and quite a bit of noise immunity.

In fact, some days FT8 and FT4 are the dominant (and sometimes only) signals you will see on some bands. The graphic above shows FT8 signals starting at 14.074 MHz and FT4 exchanges starting at 14.080 MHz. Both of these modes are just a bunch of tones shifting in frequency during an exchange window. The transmission windows are 15 seconds for FT8 and 7.5 seconds for FT4.

Setting up FT8 communications is really easy after you install the WSJT-X software. First, connect the audio from your receiver. In addition, you will benefit from connecting the software to your logging program and transceiver control. Nothing new hear for most hams and radio listeners.

Second, check your audio levels and reduce your transmit power. Most people use 5-20 watts for these modes, because that’s all you need. Finally, synchronize your PC clock to a time standard and keep it synchronized. You will find it’s easy to set this up in Windows and just forget about it.

If you are a SWL, all you need is the audio from your receiver. Tune to the right frequencies and WSJT-X will decode everything for you to follow along. When I first wrote about FT8 two years ago, it was something new. Now it dominates much of ham activity.

Weak Signal Communications Software Robots

In general, FT8 communications still require a human operator, even though the QSO sequence is largely automated.

However, some enterprising hams have fully automated exchanges with FT8 and FT4. For example, SV5DKL in Greece uses keyboard macros to automate exchanges with WSJT-X. If you follow his instructions, you can turn your PC into a robot to do your ham radio for you.

Needless to say, these approaches have caused a lot of concern in the ham community by removing the operator from the process. But I suspect they are being increasingly used. After all, you can work DXCC in a few weeks rather than years, albeit through questionable unattended operation.

One comment

  1. Michael says:

    Hello John,
    I realize these are modern times, and as such, technology changes the way we use the airwaves. I have to admit, I’m quite impressed with he results of FT8, and its abilities to work in even the worst of propagation. However, this is where my (and many others) enthusiasm for this new technology ends.

    I am a member of SKCC, FISTS, and NAQCC. Many of us have “dedicated” channels we like to use for the clubs. While certainly nobody “owns” any part of the HF Amateur spectrum, a lot of us who use CW as a primary form of communication are finding that this new breed of digital users seem to not care where and when their FT8 are being used.

    Often, there has been plenty times I have experienced an FT8’r just dropping in right on top of me and others without QRL-ing the frequency the want to use. Trust me, its very annoying when the rest of us go through the checks, and operate as considerate hams, only to be run over by what seems to be a newer generation that doesn’t care about the proper ethics and operations of Amateur Radio.

    There has been long threads of discussion about this behavior on the SKCC group list. A lot of the discussion revolves around wondering if the FT8 operator even bothers to check if the frequency intended for use is open? A lot of us on the SKCC group want to work along with the FT8 users, but also need them to follow the rules just we do. After all, it’s what makes Ham Radio a fun experience for everyone in the end.

    I know that some contact has been made to the creators of the software, asking them about frequency use, only to find out that that either the frequency is predefined, or left open for the Operator to determine. That being said, I think there has been a few letters sent to the ARRL to address this situation.

    We all want to have fun with Amateur Radio. But, if we choose to not play be the rules, regulation can be put in place that will dampen the mood and enthusiasm for this growing hobby.

    -Michael / KD9MED

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