Ray, W3PRR, asked me for help on configuring Fldigi running on a Mac with OS 10.9.4 so that it can control an Icom 7200 radio. Here’s how I did it:
1. Get yourself a plain USB-A to USB-B cable, as used with most recent computer printers. This one at Amazon will work fine. The IC7200 has a built in sound card, and the USB cable will provide both rig control and audio input/output through the one cable.
2. Make sure the OS is up to date by running OS X’s Software Update.
3. You need to install the driver for the Silicon Labs CP210 USB-to-UART bridge, which is what provides the brains for the USB-B port on the back of the radio. You can download that here.
Note: Do not connect the radio to your Mac when you install the driver. Connect the radio after you install and reboot the Mac.
4. Download and install the Hamlib radio control libraries.
5. Download and install the latest version of Fldigi.
6. Connect and power on the radio to your computer using the USB cable. Make sure that the radio is in Data mode, and make sure that Data mode is set to U, so that it accepts audio and CAT commands through the USB port. See page 43 of the Icom 7200 Instruction Manual for details.
7.In Fldigi, under Configuration > Audio > Devices, select PortAudio, then USB Audio CODEC for both Capture and Playback. Click Save before you move to the next step.
Note: If the radio is not connected and powered on, the USB Audio CODEC option will not be visible.
8. Under Configuration > Rig use these settings.
Click Initialize, then Save, then Close.
At this point you should be able to see activity in the Fldigi waterfall (ASSuming there is anyone on frequency), and you should be able to transmit from within the program. The 20M PSK31 calling frequncy, 14.070 MHz, is a good frequency to use for testing because it tends to be active.