Unit installation

FS70 Trawl Sonar System
84 974-24007001/4.1
If no sensor information is displayed on the sonar image you may
have a problem with the sensor controller board. If the internal
sensors are displayed but no external sensors are shown then the
problem may be with the catch hydrophone receiver or the
associated circuits. If only some of the sensors are displayed you
may have a problem with a specific sensor that was not detected.
You will have to troubleshoot the problem.
User Setting
If all OK and no errors are posted into the log files then the host will
download the selected “User Setting” to the head.
NOTE: If any of the above host Downlink commands have
issued a requested and a reply is not Uplinked back to the host,
those errors are posted in the log file. Therefore you are having
some Downlink or Uplink telemetry problem. If this is the case
you will have to troubleshoot the problem.
The problem may be located in the TTM/LF1 telemetry boards or
the LF1 telemetry boards located in the head. The best way to
determine the problem would be to replace the head or the TTM
with a serviceable spare unit.
Problems and the possible causes:
Problem
Action/Possible Cause
Complete system and/or calibration
failure - cable gain at maximum,
telemetry errors are logged in the file.
Check for telemetry errors. If none, then
problem is with the sonar head or the TTM
unit.
Sonar head operates correctly but
pauses periodically - may not have
sensor module data
Check Message Log for errors. If multiple
errors are present then the internal sensor
module may be defective. Check by
restarting the system.
Sonar head operates correctly but
image is skewed or distorted.
Check for calibration errors in sonar head
positioning. If calibration errors are present
then sonar head may be defective. Otherwise
check that sonar head is properly mounted in
trawl housing.