Filter
Top Products
Transducer Coverage
The area covered by the transmitted sound waves is determined
by the cone angle of the transducer and the water depth. The wide
cone angles (40°) associated with low frequencies (50 kHz) provide
a large coverage area for nding sh within a coverage width that
is approximately 2/3 of the water depth. However, this also means
that wide cone angles produce less bottom detail and resolution. As
shown in the drawing on the near right, the 40° cone angle produces
a coverage area of approximately a 20-foot diameter circle at a
30-foot depth.
The narrow cone angles (10°) associated with high frequencies
(200 kHz) provide better bottom resolution and crisper detail, but
cannot show a large coverage area for nding sh. The 10° cone
angle provides a coverage width that is approximately 2/10 of the
water depth. As shown in the drawing on the far right, the 10° cone
angle produces a coverage area of approximately a 6-foot diameter
circle at a 30-foot depth.
Dual frequency mode combines both frequencies to get the best
coverage area and contour/depth readings.
40° Cone Angle (50 kHz)
Coverage
Diameter
Depth
10° Cone Angle (200 kHz)
Coverage
Diameter
Depth
100 GPSMAP 278 Owner’s Manual
settIng uP And usIng sonAr > understAndIng sonAr