Apparently people found the “Making a Cable to Go Between a GPS device and the Kenwood TH-D7” useful, and have asked for information about making a data cable.

View of the front of the connector-side (not the best picture):

View of the top of the solder-side:

So a view from the solder-side shows the pins to be:

__(_)_(B)_(R)_(_)_(G)__
____(_)_(_)_(_)_(_)____

G = Ground
R = Red
B = Black (sometimes white)

A lot of this depends on the cable manufacturer. If for some reason it does not seem to be working, simply switch (R) and (B).