The cheap and dirty solution is to use VOX to key the radio. However, if you do that, you're going to miss out on the better features of the HRD software which let you control the rig from the computer. You must be sure to disable all the other sounds on your computer - we don't want to hear Windows beeps and bloops on 14.070.
I too like the RigBlaster Plug n' Play for digital modes. There are two things I don't like, though. It has no provision for direct FSK keying a radio that's capable. And it uses the same serial port for rig control and CW keying. That doesn't work with something like HRD that wants to use both functions. But, otherwise, it works great with my IC-7000 and IC-746. There are many other interfaces out there with USB ports now.
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