3
Back-up memory:
.......... Built-in memory stores sonar settings for
decades.
Languages:
...................... 10; menu languages selectable by user.
Sonar
Frequency:
...................... 50/200 kHz for
SeaFinder 640c DF
; 200
kHz for
FishMark 640c
.
Transducers:
.................. A dual-frequency Skimmer
transducer with
built-in temperature sensor is packed with
the
SeaFinder 640c DF
. It has 35
°
/12
°
cone
angles. A single-frequency Skimmer trans-
ducer with built-in temperature sensor is
packed with the
FishMark 640c
. It has a
20
°
cone angle. Transducers operate at
speeds up to 70 mph (61 kts)
Watts:
...............................
SeaFinder 640c DF:
4,000 watts peak-to-
peak/500 watts RMS.
FishMark 640c:
1,500
watts peak-to-peak/100 watts RMS.
Sonar sounding
Depth capability:
...........
SeaFinder 640c DF:
1,500 feet (457 me-
ters).
FishMark 640c:
800 feet (244 meters).
Actual capability depends on transducer con-
figuration and installation, bottom composi-
tion and water conditions. All sonar units
typically read deeper in fresh water than in
salt water.
Depth display:
................ Continuous display .
Audible alarms:
............. Deep/shallow/fish/zone.
Automatic ranging:
....... Yes, with instant screen updates.
Auto bottom track:
........ Yes.
Zoom bottom track:
...... Yes.
Split-screen zoom:
......... Yes.
Summary of Contents for FISHMARK 640C
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Page 48: ...42 Sonar page in Split Zoom Sonar Chart display mode Sonar page in Digital Data display mode ...
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