I thought I'd pass on a little note that the APRSIS32 software works really well with the Kenwood TH-D72 connected through the USB port as both a receive only tracker or as an IGate and digipeater. When you configure the port just select the KWD710(APRS) port type. Make sure the radio's APRS modem is off when you start APRSIS because the software wants to start it up. Here is a screen shot of my TH-D72 hooked up to a 2 meter vertical dipole displaying all of the station it is receiving through RF. I'm not digipeating with it in this capture, but I could if I wanted to. I do have iGating turned on.