Detection range (depth) of a fish finder depends upon the frequency used for ultrasound transmission. In principle, the higher the frequency of ultrasound, the shorter the propagation range can be. The wavelength of high frequency ultrasound is short, and its directivity angle is narrow, which enables detailed searches, but it attenuates significantly while travelling through water. Low frequency ultrasound is characterised by its long wavelength, wider directivity angle and high level of tolerance toward underwater attenuation, hence enabling wide-area-searches in deeper water. To summarize, you can choose low frequency if you are searching in deep water and high frequency if you are conducting a detailed search in shallow water. Further, when using low frequency ultrasound, you may be able to conduct more precise deep-water searches by adding an optional Power Adapter, which amplifies the transmitter power to a few kilowatts. Please note, however, that when using the Power Adapter, a dedicated transducer capable of handling higher transmitter power will be needed.

The Garmin Echo 551DV is one of the newer and more advanced models in the Garmin line of fish finders and it’s the top fish finder under 300. It’s one of my top choices and I really think that it’s the best fish finder for the money. It offers the best fishing sonar and a large clear display. The transducer has 500 watts of power, which allows the wave to go as deep as 2300 feet. It comes from the echo fish finder series that are known for their great accuracy.

While many fish finders point directly underneath your boat, higher end units like this one will sweep to the sides as well. Considering that you are casting out from the ship rather than dangling lines beneath it, side sweeping is much more valuable as it allows you to find fish wherever you are, rather than finding them, moving the boat, and then trying to catch them.
The intensity of the sonar return from a hard bottom will be different to one from a hard bottom. Your fish finder uses colour to show this difference. In the standard colour palette of the Deeper display, the colour varies from dull brown (softest) to intense orange (hardest). In the day mode colour palette (see screen shot), the difference is even easier to see, with the colour ranging from purple (softest) to red to orange to yellow (hardest).

When checking the transducer, the most important feature is the cone angle. For a bigger perspective of the verges underneath, choose a bigger degree on the cone. The wider beam gives more coverage of the under water and allows locating more fish within it. However, its drawback is the quick loss of strength. Due to this, it cannot penetrate the water as deep as the narrow cone. The narrow one can go really deep even in shallow waters and can also give information on the composition of the bottom.
Higher frequencies, such as 192 or 200, are ideal for fishing in shallow water. Lower frequencies, such as 50 or 83, are perfect for deep water fishing. To find the top fish finder for the money, knowing what area you’re planning on using it in will lead to more catches. Remember that the higher the frequency, the more detail you’ll have on the screen.
The colour on your display is crucial here for identifying a brush and logs. Because they will send a different frequency of sonar return, your fish finder will show them in a different color to the bottom (otherwise, it will just look like a hump). So make sure you choose a color palette that will highlight this difference. In the Deeper App, choose either the Classic color mode (where brush and logs will show green, like vegetation) or the Day color mode (where they will show purple).
The sound wave spreads as it gets further from the transducer. The wider the cone, the larger the coverage area, but the as the cone angle spreads, sensitivity diminishes. A 20-degree cone is considered a versatile angle for fishers who frequent different water depths. More advanced devices come with double and triple beams, ideal for scanning deep water depths.
Kiss has collectable action figures. Does Madonna have action figures? Eh, better not answer that one. Back in the day, I was a member of the Kiss Army. What sort of fan club does Madonna have? Better step away from that one too. Pluto will always be a planet to me, and Kiss is already in *my* rock and roll hall of fame. I love the smell of flamethrowers and flash pots in the morning … smells like … victory.
A fishfinder or sounder (Australia) is an instrument used to locate fish underwater by detecting reflected pulses of sound energy, as in sonar. A modern fishfinder displays measurements of reflected sound on a graphical display, allowing an operator to interpret information to locate schools of fish, underwater debris, and the bottom of body of water. Fishfinder instruments are used both by sport and commercial fishermen. Modern electronics allows a high degree of integration between the fishfinder system, marine radar, compass and GPS navigation systems.

NO INSTALLATION REQUIRED: That got your attention, didn't it? If you're on a budget, and don't want any sort of permanent installation mods to your boat, the Humminbird Smartcast series may be your answer. You simply cast the green transducer to the spot where you want to investigate, and the signal comes back to the wrist module (RF30) or the traditional display model (RF15). This series doesn't have a lot of bells and whistles, but for my kind of fishing/paddlecraft, it may be a great solution.
ONE SMALL STEP FOR MAN, ONE GIANT LEAP FOR PADDLING_KIND: In the 2009 ICAST article, I mentioned a combo system that was in the new products exhibit, but wasn't available at the time of the show. It's most certainly available now, and that unit is the Humminbird 385CI. Like us, fish seek comfort, safety, and food. This unit will allow you to gather "data" that you can process in to fish finding "information".
A fish hook is a device for catching fish either by impaling them in the mouth or, more rarely, by snagging the body of the fish. Fish hooks have been employed for millennia by anglers to catch fresh and saltwater fish. Early hooks were made from the upper bills of eagles and from bones, shells, horns and thorns of plants (Parker 2002). In 2005, the fish hook was chosen by Forbes as one of the top twenty tools in the history of man.[2] Fish hooks are normally attached to some form of line or lure device which connects the caught fish to the angler. There is an enormous variety of fish hooks. Sizes, designs, shapes, and materials are all variable depending on the intended purpose of the hook. They are manufactured for a range of purposes from general fishing to extremely limited and specialized applications. Fish hooks are designed to hold various types of artificial, processed, dead or live baits (bait fishing); to act as the foundation for artificial representations of fish prey (fly fishing); or to be attached to or integrated into other devices that represent fish prey (lure fishing).