Angles

A fishfinders transducer uses sonar to see what is underneath it. When it shoots its sound wave it goes out in a cone shape. Depending on the angle it uses, it might show more or less of the bottom.

For example when you shine a flashlight the light comes out of the but goes out at a certain angle to help the light expand. This is like a fishfinder works because the sound wave goes out with an angle too. The bigger the degrees, the more it stretches out. Some high end fishfinders have up too to 120 to even 150 degree angles of view.

Frequencies

Another important measurement is that of frequency. This is the frequency of the sound wave signal that the fishfinder uses. A lower frequency like 50 kHz is good for deep water and you can go a long distance without splitting apart. A higher frequency like 200 kHz would work very well in a shallow water surface like a lake or pond. Most fishfinders allow you to set the transducer frequency based on your preference for you to find the most fish.

Detection

A very useful feature into fishfinder is the ability to tag possible fishes and other marine life on the display. By sensing what kind of sonar is returned from an object, your fishfinder can intelligently guess if it is a fish or not.

Transducer

On this web site and you’ll run across the term transducer frequently. The transducer is the main sonar device on your fishfinder. It actually shoots the sound beam and listens for the return.

It is very important that you transducer be positioned correctly on your boat. You want to keep it away from your motor. Some transducers are made to be mounted in the water. Some can be mounted on the hull of your boat. Still, some other fishfinders need to be mounted by drilling a hole in your boat.

Display

The display of the fishfinder is the part of the device that you actually look at the sonar results on. Obviously, the larger the screen the easier it will be for you to read it when you are out fishing on your boat.

Some displays are rated with high resolution and have lots of pixels. Some displays come in black and white, others come in color.

Color Or Black and White Fishfinders

Should you buy a black and white or color fishfinder? That is a good question.

The start with the black and white models are much cheaper to purchase and are going to use less battery power. If you do not have a big marine battery have lots of other devices under boat, these black and white fishfinders will be very good.

This style is in grayscale it is either true black and white or has up to 16 at different shades of gray. You’ll learn to interpret them. A black and white fishfinder can give you as much information as a color one will.

The benefit of the color fishfinder is that they’re much easier to read because there is a larger gradient. The downside of these color fishfinders is that they require much more power to operate. Also, some of the cheaper ones washed out in direct sunlight and are very hard to read. You also have to worry about setting the displays contrast and brightness, as well as operating every other tool on it.

We recommend that you buy the best fishfinder that you can afford. If it is black and white that will be OK.