Simrad SRT - Page 17

| 17
Preventive maintenance | SRT LAN radar sensor S-band down-mast Service Manual
Extended tune
The extended tune allows for initial tuning and adjustment of the radar system.
A
B
C
D
Adjustment options
A Tuning
B Pre-STC
C Performance monitor
D Sidelobe suppression
¼ Note: The status and controls icons are located on the right side of the extended tune image.
The adjustment settings on the left side are to be carry out by the service engineers.
Auto coarse tune adjustment
The coarse tune can be automatic or manual. The Auto coarse tune adjustment is used to do
initial automatic tuning of the radar system and to adjust the radar when a new magnetron
has been fitted. Automatic tuning will work well in most installations. Manual tuning is used if
it is required to adjust the result from an automatic tuning.
When automatic tuning is selected, a progress bar indicates the status. The value is stored
automatically when tuning is completed.
Coarse tune
Be sure that radar is on 24 Nm range. Set the Fine Tune on manual at 50% .
STC and FTC filter at 0%. IR off. Performance monitor On.
Adjust the Coarse tune to obtain maximum echoes brightness on the screen with 80% on
tune bar.
¼ Note: Adjusting the Coarse tune from 0% to 100% causes the echo brightness and target
detection to increase then decrease again as the tuning is increased. Adjust the course
tune to give maximum echo brightness and target detection. Some small targets that were
previously hidden will appear on the panel.
The Coarse tune position will be automatically saved.
Tuning indicator
The tuning indicator is used to adjust the tuning bar. When the tuning indicator is set at
maximum, the tuning bar indicator is displayed at approximately 80%.
Tuning oset
The tuning offset sets the offset limits of the coarse tune. It should be adjusted for maximum
radar returns.