Standard Horizon Ff520 - Manual (Page 40)

Page 42 FF520
surface clutter, and increasing the STC strenght until the image on the screen cleans up.
Please note that in very shallow waters it is usually better to switch to manual gain mode
to reduce gain fluctuation due to rapidly changing bottom conditions. 2) Using Surface
Declutter, increase the Surface Declutter value until the surface declutter disappears
completely.
7.11 WHY DO I NEVER SEE FISHES IN THE RANGE BETWEEN 0
TO 2 FEET?
The minimum range of the Fish Finder is 2 Feet. In this interval the Fish Finder can detect
neither the bottom nor any target.
7.12 HOW CAN I REDUCE THE SURFACE CLUTTER?
You can act by: properly setting the STC as described at 7.10 and also by increasing the
NOISE LEVEL and reducing the GAIN or the GAIN OFFSET (if you are in auto gain mode).
However please note that a strong attenuation of surface clutter may also reduce the
capability to detect targets.
7.13 THE FISH FINDER IS IN AUTO GAIN MODE BUT THE PIC-
TURE DISPLAY TOO MANY SMALL TARGETS, WHAT SHALL
I DO TO REDUCE THE SCREEN CLUTTER?
Try increasing the NOISE LEVEL or decreasing the GAIN OFFSET.
7.14 IN VERY SHALLOW WATERS WHEN THE AUTO GAIN MODE
IS SELECTED THERE ARE FLUCTUATIONS IN THE BOTTOM
PROFILE WIDTH AND ITS COLOR REPRESENTATION. WHAT
SHOULD I DO?
In very shallow waters the environment situation (bottom/water condition) change very
quickly thus causing the auto gain algorithm to create oscillations while trying to set optimal
GAIN value for each situation. To avoid this it is advisable to switch to MANUAL GAIN mode
and fine tune the GAIN to a fixed setting.
7.15 IN VERY DEEP WATERS EVEN SETTING THE GAIN TO ITS
MAXIMUM VALUE I CANNOT SEE THE BOTTOM WHAT
SHALL I DO?
Try decreasing the NOISE LEVEL. If still the bottom is not visible there is nothing you can
do, the bottom echo is simply too weak to be detected.
7.16 GPS CHART PLOTTER SHOWS NO DATA WHEN VIEWING
THE FISH FINDER PAGE
This may be due to the FF520 having an issue. To confirm, listen to the depth transducer
for the transmit pulse. If the pulse is not heard the FF520 is defective.