By Jeffry Komori (KH6JUZ-1) and David Harris (N6UOW), Labor Day Weekend 2011

Using the D72A on 9600 bps.

• You cannot use a 9600 TNC to connect to the D72A in 9600 APRS mode. (You time out, Station Busy...)
• You must connect a USB or Serial Cable to the D72A, in order to set hbaud 9600.
• There are no radio menu commands to switch the TNC?
• It seems like the TNC mode defaults to a blank TNC, but inherits the mycall.
• The unit resets its TNC settings when you power-cycle the radio...
• like when you insert/remove the external power jack...
• ...so, your terminal/packet program needs to initialize all those settings every time.
• The D72A DOES remember all your APRS settings when you cycle power
•  

"Lynn W. Deffenbaugh (Mr)" ldeffenb

As you have noted, the APRS mode of Kenwood APRS radios is output only to a PC.  In order to transmit, the client program must switch the TNC out of APRS mode and into KISS mode, do the transmit, and then switch it back to APRS mode for continued radio-based functionality.  Kenwood did not provide for these switches to be easy and packets can get lost in the shuffle.  Furthermore, the ID of the radio will sometimes adopt the ID of the client program and not go back to its internal MYCALL configuration until the next power cycle.
--  Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32