Greetings: I have posted here and at other Sites fishing for information on interfacing a Mac to a Transceiver running the FLdigi Application but I found almost nothing. I finally decided to dig in deep and do it my way... I picked up some USB to Serial interfaces and some Audio Interface stuff and finally after many attempts in the FLdigi configuration menu I was able to key the Paragon with TX buttons on FLdigi. I plan to put all the pieces into a nice metallic enclosure and eventually do a write-up on the method. I'm certain that there are plenty of Mac users who would enjoy knowing how to make it all happen. There are plenty of Boxes being sold to interface PCs but none that I could find that claim to work with a Mac. USB is USB and the PL-2303 or FT-232 make excellent interface drivers for the PTT activity and, the software drivers are easily found on the WWW. Look for more on this interface as I record the process and write a story of how to make it all happen with a Mac and just one small handful of parts.