Gps Ff Combo

How to Choose a Lowrance Fish Finder

When shopping online for discount marine electronics, such as a Lowrance fish finder, it helps a lot to understand a bit about the technology you are shopping for. Here is a quick explanation of some of the terms you will encounter.

Cone Angle

First of all, fishfinders use sonar to probe the depths of the sea or lake bed and determine a picture of what lies beneath the water. When you shine a flashlight into the darkness, the light fans out creating a cone that is narrow at the source and wider at the distant end. Electronics does the same thing. The Cone Angle refers to the spread of the beam at the distant end, so a 90 degree beam offers more coverage than a 20 degree beam. Multi-beam systems, as the name implies, send out more than one sonar beam, cumulatively offering a much wider field of view. The Lowrance HDS-7 Fishfinder and GPS Chartplotter series offer a stunning 120 degree view with superior clarity and magnificent detail.

Frequency

The frequency of the sonar signal is measured in KHz. In general the lower the fish finder’s frequency the deeper the signal can penetrate beneath the surface. For very deep waters 50 KHz will give you deep penetration using a relatively narrow cone angle. Much higher frequencies tend to have wider cone angles and do not penetrate the water to the same degree. Equipment operating at a frequency of 200 KHz is well suited to covering a wide area in a shallow lake and can result in a more finely detailed picture of what lies below the surface. Frequency is usually adjustable and dual frequency options are common.

Fish Targets

When the sonar beam encounters an object it returns a signal to the fish finder. The sensitive electronics in the unit analyze the characteristics of the signals returned and are able to distinguish between marine life and other objects. Fish targets are typically represented as a fish symbol on your unit’s screen.

Thermoclines

A thermocline describes a layer of water that is at a different temperature from the waters around it. Thermoclines form rapidly in response to changing conditions or they can be a permanent feature of a certain ocean area. Lowrance fish finders represent thermoclines as lines on the display.

Transducer

The transducer is the powerhouse of the fish finder. It controls the frequency of the sonar beam and sends and receives the signals that are interpreted by the equipment into graphical representations. Three important things to know about the transducer are how it mounts on the boat, what frequencies it supports and the cone angle it produces. Transducers commonly mount on the transom, or hull, out of the way of the motor. Transom-mounts are the most common and easiest to install. Some models with high frequency capable transducers may need to be mounted through the hull, which can be a complicated installation requiring a hole to be cut on the hull. The Lowrance HDS-7 Fishfinder and GPS Chartplotter series and the Lowrance HDS-5X fishfinder series come with your choice of 83/200 KHz or 50/200—KHz transducers.  

Display Screen

All the detail in the world is not worth much if you can’t see it! Many fish finders use LCD color displays. Generally the larger the number of pixels, the better the quality of the display. Grayscale displays use shades of gray to distinguish between natural and artificial structures, the lake bottom and the type or size of the fish. CRT displays come at a higher price but offer higher resolutions and better display quality.

Lowrance makes a full range of fishfinders, FF/GPS/Chartplotter combos and offers a full range of other marine electronics for boating professionals and enthusiasts.

Garmin Fishfinder 140 with 4.7-Inch Display and Dual-Beam Transducer $127.99 The Fishfinder 140 combines a 4-inch grayscale display and Garmin’s exclusive fishfinder technology into an entry-level sonar that’s perfect for any vessel where space is at a premium.Fishfinder 140′s included dual-beam transducer provides excellent shallow-water performance, and the wide viewing angle lets you see fish even off the sides of the boat. With an easy-to-ready grayscale display and ba…

Garmin Fishfinder 90 with Dual-Beam Transducer $109.99 The Fishfinder 90 wraps simple operations and Garmin?s exclusive fishfinder technology into an entry-level sonar. It?s perfect for any vessel where space is at a premium. Dual-beam transducer operation gives you better shallow-water performance. The wide viewing angle (60°) lets you see fish even off the sides of the boat. With a basic black-on-white display, the Fishfinder 90 has one of the shar…