Eagle Electronics 242 SONAR User Manual


 
53
Noise Reject and ASP
The ASP (Advanced Signal Processing) feature is a noise rejection
system built into the sonar unit. It constantly evaluates the effects of
boat speed, water conditions and electrical interference and automati-
cally gives you the best display possible under most conditions.
ASP is an effective tool in combating noise. In sonar terms, noise is any
undesired signal. It is caused by electrical and mechanical sources such
as bilge pumps, engine ignition systems, wiring, air bubbles passing
over the face of the transducer and even vibration from the engine. In
all cases, noise can produce unwanted marks on the display.
Noise Rejection menu.
The ASP noise rejection feature is especially useful because, typically,
it lets you operate the boat at all speeds without adjusting the sensi-
tivity or other controls.
The ASP feature has three settings — Off, Low and High. When first
turned on, noise rejection is set on low. If you have high noise levels,
try using the high ASP setting. If, however, you are having trouble
with noise, we suggest you take steps to find the interference source
and fix it, rather than continually using the unit with the high ASP
setting.