If you currently have Packet Radio equipment then all you need
to do is to Download the freeware version of UI-View. You can do this by Downloading the software from http://www.ui-view.org/

Setting Up UIVIEW

UI-View / UIDIGI UNPROTO Settings

APRS,TRACE7-7
(Quick and easy digi’s via 7 stations this is the best setting - This is mostly used in the UK)

APRS,WIDE3-3
(The same as trace, but uses Wide digi’s - Mostly used in the US)

APRS,RELAY,TRACE3-3
(good for mobiles)

APRS,TRACE7-7,WIDE7-7
(don't use this it causes some TNC's to crash)

Setting up the Kenwood THD7 Handheld

If you have the cable to connect the kenwood to PC then:
Connect everything up (ensure its switched off)
Set radio to TNC & Packet [TNC] twice
In Setup -> Comms Setup in UI-View select host mode KISS
Click Setup and Select TNC2, Then you should be running.