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Hermes Manual 1.0.1
Iridium
Iridium is a critical feature of the Hermes; without a connection to the Iridium network, the
Hermes’ position data cannot be transmitted out, and positions of other beacons cannot be
received.
The Hermes’ Iridium modem is always in an active state. The LCD displays the Iridium signal
strength on the top of the screen. If there is an exclamation point, the Iridium modem is not
connected to the Iridium network.
Pictured: Iridium Strength Bars; no signal, not registered, low signal, full signal
Internal GPS
While the Hermes will function with its own GPS inoperable, the internal GPS can be used to
acquire a bearing and distance between the Hermes and the device currently displayed on the
LCD.
The display will show the Lat/Long in decimal degrees of the Hermes on the “My Location” page.
When the GPS has a position for this screen,
GPS
will be displayed at the top of the screen.
The Hermes’ internal GPS updates every 30 seconds, and transmit its most recent position over
Iridium every 30 minutes. If the Hermes has not acquired an updated fix after 15 minutes, the
GPS logo will appear as a strikeout.
Pictured: Hermes GPS has not been updated, Hermes GPS has a current position
NMEA Output
The Hermes has the ability to output NMEA-0183 TLL (Target Latitude and Longitude) signals
from its bottom Chogori connector to a connected chart-plotter.
If the Hermes is not connected to the chart-plotter when a new position arrives, pressing the
NMEA
button while viewing the position on-screen will output the appropriate string of that
position from the port. At that time, an
N
will momentarily appear on the screen between the
Iridium and battery symbols on the display.
If a new position from a beacon arrives while connected to the chart-plotter, the position is
immediately pushed from the NMEA port.
Received Messages from Beacons
As messages are received from remote devices, the Hermes will update the NMEA index for that
particular device to display the time and location of the most recent position. If a new position
