I called into the recent training which featured WB4APR discussing APRS.
He is credited with its creation.
I was surprised to learn that the control head for the Kenwood D710A can
be connected to other radios.  WB4APR uses it with his Icom handheld.

The control head costs $200 and he recommended the PG5J interface kit.
Of course, the control head won't control the frequency or memory of
your handheld, but it can serve as  a TNC.

It seems that there is also a way to get the APRS text messages to
speak.  Has anyone explored all these bells and whistles?

The atldiv.org/training.htm lists other webinars - I used the dial in
phone number to hear the session.


Here is some info about the control head.


RC-D710
The APRS(r) upgrade for your transceiver

TNC for 1200/9600bps packet communications 
 The RC-D710 operates as an AX.25-compliant TNC (Terminal Node
Controller) for 1200/9600bps packet communications. 
 
 
APRS(r) (Automatic Packet Reporting System) 
 Connecting the RC-D710 via the optional Interface Kit (PG-5J) to a
transceiver adds APRS functionality, as provided by the TM-D710A FM dual
bander. 
 Note: Since the RC-D710 connects to the data terminal of your
transceiver, control of another transceiver is not possible. Also,
please be aware that Kenwood cannot guarantee the performance of the
transceiver to which the RC-D710 is connected. 
 
 
Full control of TM-V71A & TM-D710A 
 The RC-D710 can replace the TM-V71A control panel to enable all the
features of the TM-D710A. It can also be used as the control panel for
the TM-D710A.