Furuno 1732, 1753C, 1742, 1733C, 1752, 1723C, 1762 Sounder system setup menu description con’t, Tvg

5. CUSTOMIZING YOUR UNIT

Sounder system setup menu description (con’t)

Item	Description	Settings
TVG	TVG (Time Varied Gain) compensates for propagation	0-9
(LF, HF)	attenuation of the ultrasonic waves. It does this by
	equalizing echo presentation so that fish schools of
	the same size appear in the same density in both
	shallow and deep waters. In addition, it reduces
	surface noise. Note that if the TVG level is set too
	high short range echoes may not be displayed.
Echo Offset	If the on-screen echo level appears to be too weak or	-50 - +50
(LF, HF)	too strong and the level cannot be adjusted
	satisfactorily with the gain control, adjust echo offset
	to compensate for too weak or too strong echoes. The
	default setting for both HF and LF is zero.
Bottom Level	If the depth indication is unstable in automatic	-100 - +100
(LF, HF)	operation or the bottom echo cannot be displayed in
	reddish-brown by adjusting the gain control in manual
	operation, you may adjust the bottom echo level
	detection circuit, for both LF and HF, to stabilize the
	indication. Note that if the level is set too low weak
	echoes may be missed and if set too high the depth
	indication will not be displayed.
KP Pulse	Selects source of keying pulse.	Internal, External (See
		installation manual.)
Smoothing	Smooths echoes to present stable display. The higher	SM1-SM4, OFF
	the setting the greater the smoothing.
TLL Output	Outputs cursor position to external equipment.	ON, OFF
STC (HF, LF)	Adjusts STC level for the high and low frequencies,	0-10
(For ETR-30N only)	and is useful for suppressing surface noise. The
	setting range is 0-10; the higher the setting the
	greater the extent or suppression. Setting 10
	suppresses noise up to several meters. Turn off the
	STC when there is no noise on the screen, otherwise
	weak echoes may be missed.
FREQ. ADJ. (HF, LF)	Interference from other acoustic equipment operating	-10 - +10
(For ETR-30N only)	nearby or other electronic equipment on your boat may
	show itself on the display. You may suppress these type
	of interference by adjusting frequency.
TARGET ECHO	Sets fishing objective. Normal for general fishing,	Normal, Surface
(For ETR-30N only)	Surface for detecting surface. Pulse repetition rate is
	higher than Normal on the specified transducer.
SENSOR SETUP	Offsets speed, depth and water temperature	See next section for
(soft key)	indications and speed of sound.	details.

5-31