Ambient Noise; Fishing Gear Noise - Simrad ME70 Installation Manual

Simrad ME70 Installation Manual
wide bandwidths are necessary – the noise from components, transistors or other analogue
electronic may be a limiting factor.
Related topics
Installation summary, page 46
Installation principles, page 50
Acoustic noise, page 65

Ambient noise

Ambient noise is usually not a limiting factor for ME70 performance.
The ambient noise may be split up as follows:
• : Air bubbles, seismic disturbances, waves, boundary turbulence, etc.
Sea noise
• : Fish, mammals
Biological noise
• : Other vessels, interference
Man made noise
•
Precipitation noise
In some areas, where many vessels operate together, the engine and propeller noise from
other vessels may be disturbing. Interference from hydroacoustic instruments located in
other vessels may also be a limiting factor. The sea noise depends on the weather conditions.
In bad weather the sea noise can be quite high due to the waves.
Related topics
Installation summary, page 46
Installation principles, page 50
Acoustic noise, page 65

Fishing gear noise

Whenever your fishing gear is in use, it will create noise.
A bottom trawl, for instance, is a considerable source of acoustic noise. Still, this noise from
the fishing gear will seldom be a limiting factor for hull mounted sonars or echo sounders.
However, for operation of a catch monitoring system or a trawl sonar, with the transducer
placed on the trawl, the gear noise is one of the main contributors to the noise level.
Related topics
Installation summary, page 46
Installation principles, page 50
Acoustic noise, page 65
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: Heavy rain or hail
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