RADAR OUT
The receivers can simulate a Doppler RADAR commonly used on agricultural equipment for detecting
speed. The GPS receiver is always calculating speed and can generate the signals, which can be
used by equipment requiring RADAR input. The receiver is normally configured at the factory for
RADAR output.
To use this feature, a special cable from RAVEN will be needed. It should be noted that the GPS can
only determine speed when it is navigating. If a tree line blocks to many satellites or if for some other
reason the Receiver is unable to navigate, then the RADAR output could become invalid.
The scaling factors and timing controls that govern the operation of this feature can be controlled via
a serial configuration message as defined in the serial Protocol Definition document. The receiver
uses default settings that should provide reasonable operation without the need for special configura-
tion.
ADVANCED MESSAGE FORWARDING
The Invicta 115 receiver supports advanced message forwarding in systems where the application is
designed to take full advantage of this feature. When enabled, all messages received on port B of the
receiver will be time tagged with GPS time and output on port A in a special format.
The special format is basically just a prefix that includes the time tag. The time tag is a very important
since it is referenced to GPS time and provided with millisecond resolution. It can be used to elimi-
nate latency issues. Latency is usually only an issue in systems where GPS positions are used to
locate data coming from another sensor. If not accounted for, the latency of output can show up as
positional errors.
The advanced message forwarding takes care of latency problems in systems where the other sen-
sor can output NMEA style messages. This feature would also be useful in systems with limited serial
ports if the application developer were to take advantage of this feature.
INSTALLATION
Start by selecting a location for each of the various parts of the system. Do not route the cables or
permanently mount the Invicta 115 receiver yet. Once the system is operating, route the cables and
permanently mount the Invicta 115 receiver. This will reduce the amount of trouble if a problem is
found in the initial locations.
INITIAL POWER UP
Invicta receivers are reverse power protected to prevent damage to the receiver if you follow these
steps:
Turn off all the equipment on the machine. The receiver draws very little power and this test will only
take a few minutes. All other equipment should be off because it might interfere with the receiver.
Once the Invicta is working, turn on the other equipment and watch for problems.
Apply power to the receiver by connecting the black wire to the negative (-) and the red wire to the
positive (+) post on the power source (most likely the battery). To check power connections connect a
lightbar or some other serial interface device to the Invicta 115 receiver. If attached to a lightbar, it
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