Lowrance electronic X126DF, X135, X136DF, X125 manual How Sonar Works

Transmitter:	X136DF, X135 and X126DF:
	4,000 watts peak-to-peak/500 watts RMS.
	X125:
	2,400 watts peak-to-peak/300 watts RMS.
Sonar sounding
depth capability:	X136DF: 2,500 feet (762 meters).
	X126DF: 1,700 feet (518 meters).
	X135: 1,000 feet (305 meters).
	X125: 800 feet (244 meters).
	Actual capability depends on transducer con-
	figuration and installation, bottom composi-
	tion and water conditions. All sonar units
	typically read deeper in fresh water than in
	salt water.
Depth display:	Continuous display .
Audible alarms:	Deep/shallow/fish/zone.
Automatic ranging:	Yes, with instant screen updates.
Auto bottom track:	Yes.
Zoom bottom track:	Yes.
Split-screen zoom:	Yes.
Surface water temp:	Yes.
Speed/distance log:	Optional (requires optional speed sensor).

NOTICE!

The storage temperature range for your unit is from -4 degrees to +167 degrees Fahrenheit (-20 degrees to +75 degrees Celsius). Extended stor- age in temperatures higher or lower than specified will damage the liq- uid crystal display in your unit. This type of damage is not covered by the warranty. For more information, contact the factory's Customer Service Department; phone numbers are listed on the last page.

How Sonar Works

Sonar has been around since the 1940s, so if you already know how it works, skip ahead to the next segment on the typographical conventions used in this manual. But, if you've never owned a sonar fish finder, this segment will tell you the under water basics.

Sonar is an abbreviation for SOund NAvigation and Ranging, a technol- ogy developed during World War II for tracking enemy submarines. (Lowrance developed the world's first transistorized sportfishing sonar in

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