HF, or high frequency, as it’s known is without a doubt the HF amateur radio bands have exploded with the advent of the digital modes. Although the digital modes do require some further education on hardware, software and operating procedures. There’s two important things to remember when running the HF digital modes” ALC and computer clock accuracy.
Setting the ALC on your rig for the digital modes can be done many ways yet the most effective method is to turn your RF output to 100%, back the mike gain down to zero. Now begin advancing the mike gain until you see the ALC move just barely, when it does then you should back the mike back down until the ALC stops. This mike setting will do well most of the time but you should always monitor it to insure your signal isn’t being over driven. The second thing to watch is your computer clock. Granted this is mostly for the various flavors of JT and Ft but other modes benefit from a correctly set clock as well. Not only that but your logs will be a great deal more accurate. A popular application for PC clocks is Dimension 4 by Thinking Man Software. For a Mac you can set the clock using these instructions from MacInstruct.com, and docs.slackware.com has the answer for Linux users.