Interphase Twinscope Operation Manual page 32

NORM
NORM
RESET
FULL SECTOR
SCAN
NORM
RESET
FAR FORWARD
SECTOR SCANS
NORM
Sector Width & Steer Adjustment
The large rotary knob can be used to both adjust the beam
scanning width and the direction of the scanning sector.
For example, you may not want to scan the full 90 degree
sector from the surface ahead to beneath the boat, but
instead only to scan from the surface ahead to a certain
depth below the surface.
Press the soft key labeled "BEAM" to bring up a sub-
menu of beam adjustment choices. By pressing the soft
key labeled "WIDTH", the rotary knob can be used to
adjust the scanning sector width. The actual sector size
will be shown on the display as the BEAM width is
adjusted.
By pressing the soft key labeled "STEER" the resulting
sector can then be steered throughout the possible 90
degree sector (from directly beneath the boat to the
surface ahead).
The RESET button can be used to quickly select three
popular scanning sectors. If the RESET button is pressed
once, the Twinscope will return to the full 90 degree
sector scan (from straight ahead to below the boat),
pressing RESET again will put the Twinscope into one
of three far forward sector scans (each sector is
approximately 12 degres wide).
Beam Speed (Resolution)
In its normal scanning mode "NORM", the Twinscope
will send out 50 forward beams and will alternate
between a forward beam and the down-looking beam. In
the "FAST" position, only 30 beams will be used and the
Twinscope will send 5 forward scanning beams for every
down-looking sample. In the "DETAIL" mode, the
Twinscope sends out 90 beams, one every 1 degree for
the maximum resolution, but also at the slowest speed. In
the FAST mode, the picture will have less resolution than
in the DETAIL mode.
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