Furuno NAVNET 1833 - Manual (Page 61)

2. RADAR OPERATION
2-27
2.19 Echo Stretch
Normally, the reflected echoes from long range targets appear on the display as
weaker and smaller blips even though they are compensated by the radar’s
internal circuitry. The echo stretch function magnifies these small blips in all
ranges. Two types of echo stretch are available: ES LOW which stretches
echoes in bearing direction and ES HIGH which stretches them in both range
and bearing directions.
"LOW" Echo stretch "HIGH" Echo stretch
Bearing
direction
Bearing
direction
Range
direction
Echo Stretch OFF
Target
Types of echo stretch
This function magnifies not only targets but also sea clutter and radar
interference. For this reason, be sure sea clutter and radar interference are
properly suppressed before activating the echo stretch.
1. If not displayed, press the [HIDE/SHOW] key to show the radar soft keys.
2. Press the SIGNAL PROC. soft key.
3. Press the E. STR soft key to select HIGH, LOW or OFF as appropriate.
4. Press the RETURN soft key to finish.
The display shows ES H (High) or ES L (Low) when the echo stretch is on.