The Tracking menu allows user to enable the Indigo Xplorer tracking mode, disable the tracking mode, set the reporting rate, set the mailbox check rate, cancel the emergency 911 signal, view the unit reporting data, set GPS location accuracy, and set the position report format.
When wake up to transmit a location report, the device antennas must have full view of the sky; otherwise, it will fail to send. A missed report will not be resent. The entire reporting duration can take up to two minutes depending on the Iridium satellite visibility and the validity of the GPS ephemeris data. Ephemeris data saved on the GPS receiver is valid for approximately two hours allowing the receiver to obtain a hot-start fix. Report rate (time between reports) set to more than two hours forces the GPS receiver into either a warm-start or cold-start fix (~29 seconds). As a result, the device will consume more battery power and the total number of reports is significantly reduced.
NOTE: When the device is in the middle of sending a report and user forces it to power off by holding down the power button, the device will attempt to complete sending the report before shutting down. A warning message will appear on the LCD screen and will remain until either a position report is sent or failed to send. User can go back to the home screen by simply pressing the BACK button.
IMPORTANT: The total number of reports the device can send with a fully charged battery depends on three settings—the report rate, the mailbox check rate and the Accuracy.
After the red emergency button on the back of the Indigo Xplorer is pressed, user can deactivate the emergency alert by selecting the Cancel 911 option. A screen will appear with two options to choose from: (i) With Gateway Ack or (ii) Without Gateway Ack.
When With Gateway Ack is selected and confirmed, the cancellation message is queued in the Outbox to be transmitted. If the cancellation message is successfully transmitted, the emergency mode ends, the emergency LED is turned off and the top and bottom bars turn from red to blue.
Powering the device off will not cancel the emergency mode.
When Without Gateway Ack is selected and confirmed, the cancellation message is queued in the Outbox to be transmitted. The emergency mode ends immediately, the emergency LED is turned off and the top and bottom bars turn from red to blue.
Accuracy option allows user to select either Standard or Best accuracy when acquires a 3-D GPS fix. For Standard setting, the device acquires 3-D fix using saved ephemeris data in its non-volatile memory. The ephemeris is updated only when becomes invalid. For Best setting, the device always updates the ephemeris data first before attempting to obtain a 3-D fix. The Best setting takes longer for a 3-D fix. However, the probability of obtaining position accuracy to within 2.5 meters is much higher than for the Standard setting. Best setting is not recommended when operated in environments with limited view of the sky. Choosing Best accuracy setting can significantly reduce the total number of reports on a fully charged battery because of longer GPS acquisition time. Choosing Best accuracy is the same as setting the report rate to more than two hours. For both cases, the device has to update the ephemeris data.