The Digital Mode Tools
One of the really nice things about having a computer in the shack is that many of the digital modes that used to require dedicated hardware (like RTTY) can now be easily done with just a sound card and a simple interface. This makes it really easy to try out new modes without spending a fortune on dedicated hardware. It also makes it possible for programmers to create and modify new modes quickly and easily without worrying about obsoleting the old hardware.
The two digital modes that I use most often are PSK31 and RTTY. I don't do all that much of either, but now and then I'll get my feet wet by playing in a RTTY contest or working someone on PSK maybe as a new country or mode or band. There are really just a couple of programs that I use for
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For those of you who might not have seen PSK31 in action, the screenshot here from DX4WIN shows that I've got two different QSOs that I'm decoding "listening to" at the same time, with the window on the left being the primary frequency (meaning that if I were to transmit, it would transmit there) and the window on the right showing a secondary frequency QSO. Note again that this is all done in software, the radio is actually in SSB mode and all the magic happens on the computer. Some of the more advanced programs are capable of decoding many more conversations at once.
For RTTY use, MMTTY is the way to go. MMTTY is definitely the cream of the crop here, and has all the bells and whistles you could ever want. The author of MMTTY, Mako (JE3HHT) has
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Of course, there is another very well-known mode that I think can be called digital: CW. Both of my two main logging programs support sending CW directly from the program, either with macros or via the keyboard. N1MM has a very high degree of integration in that it's easy to configure macros to use during a contest that will take the callsign that you've just entered and put it into a macro along with the contest exchange, including things like a changing serial number.
However, I do use one standalone tool (which can run along with my loggers) to help me copy CW. Although I know that my CW copying skills have improved, they have quite a long way to go before I'll be able to comfortably and confidently copy even a formatted contest exchange at high (30+ wpm) speeds. Although I can copy, by ear, certain elements of an exchange (like my callsign,
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To explain what's shown in the screen shot, there are 3 window on the screen: The top window shows where in the bandpass CwGet is "listening" (in this case, it's at 592Hz, which is the audio tone my receiving is generating for the CW being received), the second window shows the decoded text, and the bottom window shows the dihs and dahs coming in. The red horizontal line is essentially a "squelch", meaning that anything below that line will be ignored. In the particular screenshot here, CwGet is copying the weekly DX Bulletin from the ARRL. (This was from their 40m broadcast, and given that I've relatively close to ARRL HQ, it's a very strong signal, so the decoding is perfect; this isn't always the case.)
Incidentally, both CwGet and the PSK31 decoder have some other interesting uses: A while ago, there was an odd hum on the output of one of the local 2m FM repeaters. I fed the audio into CwGet and I was able to figure out that what I was hearing was the CTCSS (PL) tone for that repeater, which was just a bit louder than it should have been.
I've got one more part in this series, where I'll talk about a few miscellaneous tools that didn't fit into any of the previous categories.
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