R2Sonic 2022, Operation Manual

Page: 62 / 133

Page 62 of 133
Version 3.0 Rev r000
Date 25-08-2010
Part No. 96000001
increase the strength of the bottom returns and, thus, allow for a lower receiver gain setting. If too
much power is used, the receivers can be over-driven (saturated); this will result in noisy data
and/or erroneous nadir depth readings. A good balance of source level (Power) and receiver gain is
the desired end.
6.8.3 Pulse Length: 15µsec – 500µsec
Pulse length determines the transmit pulse duration time. The Sonic 2024 pulse length range is
from 15µsec to 500µsec. The pulse length does not affect the pulse amplitude, which is determined
by the Power setting. The general guide line is to maintain as short a pulse length as possible to
optimise the resolution, but not so short as to weaken the transmit pulse. Generally, as the water
gets deeper the pulse length will have to be increased to get more ‘total’ power in the water. The
default pulse length will depend on the chosen operating frequency.
Figure 61: Transmit Pulse
6.8.4 Gain: 1 – 45
Receiver gain is in 2 dB steps from 1 to 45. This adjusts the gain of the sonar head receivers.
6.8.5 Depth Gates
The depth gate allows the user to eliminate noise or other acoustic interference by the limits set in
the Minimum and Maximum Depth.
Depth Gates are turned on or off via the drop down selection in the upper left hand portion of the
Sonic Control window.