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MOST IMPORTANT FEATURES TO CONSIDER IN A FISHFINDER:
Cone angle:
When dealing with transducers, the most important aspect is cone angle. The cone refers to how wide of a beam is sent out from the bottom of your boat. It starts out narrow at the transducer and widens as it gets deeper. The wider the degree on the cone, the larger the view of what lies beneath you will receive. As you move deeper, the coverage will widen and vice versa. Keep in mind that as cone angles widen, sensitivity begins to diminish in very deep water. Transducer cones can be purchased in ranges from 9-degrees upwards of 60-degrees, with most units falling somewhere between 16 and 20-degrees.
Cone angles widen, sensitivity begins to diminish in very deep water. A cone of 20-degrees is a perfect starting point for anglers fishing a variety of water depths.
Beam:
The standard transducer has a single beam. Better versions have a dual beam, triple beam, side beam and so forth. What each of these does is cover more water, which is a very efficient option to have when scouring the lake for fish. Some models will come standard with these accessories, while others will be an upgrade.
Models become pricier with more features but also bring in noteworthy advantages.
Frequency:
Frequencies also come into play with transducers. Most will come with either 50, 192 or 200 kHz.
The higher the frequency, the better the unit will work in shallow water conditions.
Peak to Peak:
The term "peak to peak" is used to describe the overall output power of the transmitter. The power of a sonar unit is described in Watts. When dealing with fish finders, the higher the wattage, the more efficient and powerful the overall unit will be. Low wattage will ultimately bring you slow readouts, meaning a delayed reaction for a reading of a spot you have already traveled over. The bare minimum ‘peak to peak’ power would be 600 Watts, although 2000 to 3000 Watts is certainly recommended for most anglers.
The shallower the water you fish, the less power you will need. For those that fish deep water it is best to choose the most powerful unit you can get.
Display Screen:
With the advent of new technology, color screens are bursting onto the market like wildfire.
Color screens will allow you a greater screen definition, making fish and structure literally jump out in different shades of color for easier identification.
Pixels:
The more pixels present on a screen, the better the picture will appear. 160 x 160 pixels is the bare minimum when it comes to choosing a fish finder. Again, the more money you are willing to spend, the better the product you can purchase.
240 x 240 pixels would be a great starting point, but certainly move higher if you are able to. You won't regret it in the long run.
Back Lit Display:
For those that like to fish the graveyard shift, or anglers up before the sun, having a back lit display on your fish finder is of utmost importance.
This feature will light up your screen from behind, making viewing possible under dark and non-existent light conditions. For those that crave this style of fishing, make sure the unit you are buying has this important option before you take it home.
Speed and Distance
Although standard on some units in the market, many fish finders will offer these add-ons as options. All have a place and time, and most are a personal choice in relation to your particular style of fishing.
For those that primarily troll, the speed and distance feature will certainly improve your creel count. You can tell the exact speed you were traveling when a fish strikes - important stuff for those looking to duplicate their catch.
Temperature:
Having a temperature gauge on board is extremely important as well, for the sole fact of finding warmer water or helping you locate the preferred range for fish. Keep in mind that this option will only tell you the temperature of the surface, as it is taken from the point at which the transducer meets the water.
The temperature reading helps locate your preferred range for fishing. The reading taken is of the water surface, since it is taken from the point at which the transducer meets the water.
Fixed or Portable:
Fixed fish finders can be mounted in the exact position where the boat owner desires, with wires "hidden" underneath floorboards and bow. The transducer can also be attached to either the stern, trolling motor, or hull in order for it to be out of the way and securely held. For those that go on fly-in retreats, ice fish or rent boats the portable option would be a great way to go. It can be used in a variety of situations, and the compact size and carrying case make travel a breeze. They perform as proficiently as the fixed models, with the only difference being their portability.
Anglers have the option of purchasing a fish finder that will be affixed permanently to their craft, or one that can be taken in and out of the boat with ease.
The GPS Factor
GPS or Global Positioning System uses satellite signals to pinpoint your exact location when out on the water. This feature allows you to mark productive spots and come back to them time and time again, find your way back to shore in the case of an emergency and also map out co-ordinates for your home lake through the use of mapping software.
For those that do big water fishing or certainly tournament anglers, having GPS built into your fish finder will open up a new world of fishing fun and increased catch rates.