Cable Connections

The follwoing connections are for connecting the Garmin eTrex to the TigerTrak TM-1 encoder, and the TM-1 to the Yaesu/Vertex VX-150 VHF handheld radio. The cable color codes may vary. These cables were purchased from

GPS to Encoder

This connector connects the eTrex to the TM-1. This connector is "backwards", and doesn't require a null-modem adapter to interface to the TM-1. It WILL NOT work for connections of the GPS to a computer, however. For the cables from the Purple Open Project, the data wire is brown and the ground is black.


HT Radio to Encoder

Using the right-angle plug available from the following wiring of radio to TigerTrak TM-1 works.

TM-1 Cable Mic Cable
Yellow White (TX Data) (3)
Green Red (TX Data) (1)
Blue Black (Ground) (4)

KPC-3+ to Yaesu/Kenwood 6-pin mini DIN

The diagram assumes the mini din connector sold by Iím not certain if the color scheme is standardized for the 6-pin mini din connector, so double-check the colors with a voltmeter. This connector worked for Yaesu radios with a mini DIN and Kenwood radios.

GPS to KPC3+

A GPS as well as a radio can be connected to the KPC3+. If you constructed your GPS cables as per this document. That is, in such a manner as to not require a null modem adapter. Then wire your female DB-9 according to the diagram above. This will allow you to use your GPS cables on a TigerTrak as well as the KPC3+. Of course, you may want to wire it as per the KPC3+ manual, then use a null modem adapter to use any other cables. It depends upon your needs.