Operator`s manual

Glossary of terms Appendix A-3
London (GMT). UTC is not affected by the local summertime adjustments.
Velocity – speed towards approaching waypoint.
XTE – Cross-Track-Error (-Distance), measured magnitude of the position
error perpendicular to the intended track line.
Echosounder section (with built-in echosounder function):
Alarms – can be set to sound a “beep” if the echosounder detects a target
above (shallower than) a minimum alarm depth or below (deeper than) a maxi-
mum alarm depth. The CX34/44/54 allows you to set the alarm depths and to
enable or disable both the minimum and maximum depth alarms.
A-scope – a method of displaying the echosounder information. In A-Scope
mode, the echoes are displayed in a “bar-graph” format, with stronger echoes
displayed not only in the color representing their target strength, but also in a
width representing their target strength.
Depths – DK = Depth below keel, DS = Depth below surface, DT = Depth
below transducer.
Echogram background color – is the color shown on the CX34/44/54 in the
event no target is present. There are three colors to choose from, white, blue
or black, where black is especially useful during nighttime operation when the
white background could appear too bright.
Echosounder frequency 38 (CX44/54), 50 or 200 kHz can be selected to suit
the task. 200 kHz is for general purpose and offers optimum discrimination
and a narrow transmitter beam. 38/50 kHz is for searching in a wider area,
determining bottom conditions and going the deepest.
Transducer – the transducer serves as the acoustic “loudspeaker” and “micro-
phone” to send and receive the signals through the water. They are most
often made from ceramic elements carefully built into a robust housing. The
ceramic elements change shape when a voltage is applied across them (when
the CX34/44/54 transmits a signal), and they also generate a voltage when
they encounter sound waves (as when the CX34/44/54 is receiving an echo).