Simrad EK15 Reference Manual page 278

Simrad EK15
d
Targets (40 log TVG)
Basically, this setting uses the same TVG amplification as
filtering and compensation is implemented. Only echoes detected and interpreted as
single fish are shown. The echoes are compensated for their physical position in the
beam (beam compensation). This means that fish in the outer region of the beam are
adjusted to correct size even though their echoes are weaker.
Note that this
Targets (40 log TVG)
transducers.
e
Target Mix (40 log TVG)
Basically, this setting uses the same TVG amplification as
compensation is implemented. Echoes detected and interpreted as single fish are
adjusted to their correct size according to their physical position in the beam.
Note that this
Target Mix (40 log TVG)
transducers.
f
User (Variable TVG)
This setting allows you to define your own TVG setting.
You can adjust the TVG setting using the
on the menu.
Active
Because the strength of the echoes will become weaker with increasing depth, the echo
sounder will automatically amplify the deepest echoes more than the shallower echoes.
In fact, the gain will increase proportional to how long the echo sounder "waits" for the
echoes. When you choose the TVG setting you can either switch it off (which we do
NOT recommended), or you can choose settings
The various settings control the gain algorithms, how much gain to be applied when
the depth increases. When you choose the
the depth more rapidly than if you choose the
individual fish emit smaller echoes than a school, and this makes them more difficult to
detect. In the equation the character R means "Range".
276
setting is only functional with split beam
setting is only functional with split beam
or functions. Both are located
Echogram TVG
or
20 log R 40 log R
setting, the gain will increase with
40 log R
setting. This is simply because
20 log R
, but additional
Fish
, but additional beam
Fish
.
351718/C