GT™ — Ground Track Technology

Finding lost PTTs can be a time consuming activity for researchers. If you have ever searched for a lost PTT on a tagged dead bird you know how difficult this can be. The Argos positions, at best, may tell you where it is to within 150 m: however locations from dead birds are rarely location class 3! Even then, in typical field conditions, it is like looking for a needle in a haystack.

Our new Ground Track GT™ feature switches your PTT into a conventional tracking transmitter when mortality is sensed. Now there is no need to glue a separate VHF transmitter to your PTT or have a separate antenna dangling from it.

GT™ integrates a UHF pulsed tracking transmitter, that sounds like the VHF units you are accustomed to, into the PTT. This transmitter shares the PTT’s antenna and battery, and has some unique features. GT™ has its own programmable duty cycle and the option to be activated in a mortality mode when activity ceases. It also transmits at two power levels making it exceedingly easy to find when you are right “on top” of it.

Used in the mortality mode this feature would only consume battery power when morality is sensed. However, when used in a seasonal mode, the extra power consumption must be taken into account when calculating the lifetime of a battery powered PTT.

Now if you are within a few miles of the unit, you can quickly find it with a simple receiver and small directional Yagi antenna. A receiver capable of receiving the UHF pulses will be required: we recommend the Yaesu VR-500. This small receiver when set to the CW (Carrier Wave) mode can easily detect the high power GT™ pulses from the PTT several miles away over average terrain using a 4 element “Yagi” antenna. This same receiver can also be used to monitor the Argos transmissions, and with a suitable antenna can also be used to track conventional VHF transmitters. We can supply both this receiver and a suitable 4 element UHF “Yagi” antenna.