Sensors & Software pulseEKKO, Product Manual

Page: 102 / 251

Tools and Preferences
90
Figure 5-30: Scope mode before First Break correction
The radar pulse is shown on the screen, with the amplitude plotted on the vertical axis (in
millivolts) and the time axis plotted horizontally (traditional oscilloscope format).
First Break is the first arrival of the radar wave and is used as a convenient reference point.
Before leaving Scope mode, the goal is to ensure that the First Break is correctly positioned,
near the beginning of red line at 0 ns. Locating the First Break to the right (further in time) of the
second division has no ill effect on the data, it just means that depth readings will be incorrect
and possible reflectors may be lost off the bottom of your recording window.
When using high frequency transducers, it is recommended to lift the transducers slightly off the
ground. This will result in a higher amplitude waveform and make it easier for the Auto routine
(described below) to locate the First Break.
•
Press Auto Detect First Break for the system to initiate an automatic search to place
the First Break at the correct position (Figure 5-31). Auto is generally the preferred
method of setting the First Break, however if you are using high frequency transducers,
the antenna separation is large, or there is a large amount of external noise then this
automatic adjustment may fail. In this case, try raising the antennas or transducers
slightly off the ground to allow a strong air wave to travel between the units. If you are
still not able to find the First Break, use the arrows to manually set it as explained below.