Unit installation

Troubleshooting and Maintenance
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the values being uplinked and re-written back to the DACs. The
final values written to the DACs directly represent what we refer to
as the “Cable Gain Numbers” i.e., example “6, 23” to compensate
for the signal loss through the 3rd wire.
The most important steps regarding the Downlink and Uplink
communication between the host software, the TTM and the sonar
head is completed. If any problems were detected with the TTM/
LF1 telemetry, the LF1 telemetry board in the sonar head, the CPU
board, the transmitter or the receiver boards the cable calibration
would have failed.
Motor Calibration
After the downloading of the head parameters is completed the host
software via the CPU board will request a motor calibration. The
motor driver board will come online and calibrate the motor with a
series of rotations in order to detect the optocouplers located in the
motor housing and set-up each quadrant. The 4 quadrants and
calibration numbers will be recorded in the host software “info”
page.
If the motor calibration fails the problem may be with the motor
controller board of the optocouplers located in the motor housing.
Sensors Info Request
The next step the host must know what is connected to the system
in respect to the type of sensors. A command requesting is
downlinked to the head CPU board, the CPU will request the info
from the sensors controller board, e.g., Catch sensors, temp and
depth, Door Spread sensors etc. After the controller board has
completed the detection the info is uplinked back to the host
software via the CPU, LF1 telemetry board in the sonar head, then
uplinked to the TTM via the LF1 telemetry board.
After the Host has received the information then the sensors page
including the data will be displayed on the sonar image.