The 7 Best Hand Fish Finders
7. Venterior VT-FF001
6. Reel Sonar iBobber
5. Humminbird PiranhaMax 197c
4. HawkEye Fish Trax 1C
3. Deeper Smart Sonar Pro+
2. Lucky FFW-718
1. Garmin Striker 4
The Invention Of The Fish Finder
Many sources wrongly cite Darrell Lowrance and his father Carl as being the inventors of the first fish finders, and while they are responsible for bringing it into the mainstream U.S. consumer market, they weren't the first to produce such a device. This distinction goes to the Furino brothers of Nagasaki, Japan.
In 1948, Kiyokata and Kiyotaka, owners of a small marine electrical company, were inspired to create a fish finder after talks with a local fisherman who claimed he could tell where the fish were. According to him, when bubbles rose to the surface it meant there was a school of fish below.
At the time, people already understood the properties of sound waves in water and that they reflected off bubbles, so the brothers figured they could rig a device to detect the bubbles made by fish. Kiyotaka created the first fish finder using scrap materials around their shop and Kiyokata took it onboard a fishing boat to test it. Over time they gradually improved their equipment and Kiyokata eventually earned the name "god of sardines" for his amazing ability to consistently locate schools of fish using his fish finder.
In the 1950s Darrel and Carl Lowrance, a father and son team, developed and popularized fish finders in America. Carl had learned about sonar technology while in the navy and figured out how to use the most modern transistors of the time to reduce the size of standard sonar units. The next step was to reduce the pulse length of the ultrasonic signal. The large pulses used by the navy could only detect large objects, but smaller pulses could detect small objects, like fish.
Darrel was able to reduce the pulse length to just one foot, which meant it was capable of detecting larger fish. In 1956, the Lowrances felt their device was ready and named it the Fish Lo-K-Tor. In 1958, they incorporated their business, Lowrance Electronics, and began marketing their fish finder.
How Fish Finders Work
Fish finders use sonar to detect the presence and location of underwater objects. Modern fish finders can provide a range of information, including water depth, condition of the sea bed, and distribution of fish. Some may also include thermometers allowing them to display water temperature measurements. They work by transmitting ultrasonic waves through the water and measuring the strength of the waves reflected back.
The size and depth of the object hit will dictate how strong the reflected ultrasonic wave is when it hits the fish finder's receiver. Every fish finder has a transducer, which can be mounted on a boat or any other kid of object that is sitting in the water. The transducer is responsible for sending and receiving the ultrasonic waves.
Once a reflection is received by the transducer, it is converted into an electronic signal and sent to a receiving circuit in the fish finder. The receiving circuit amplifies the signal and then a processor turns them into the images displayed on the fish finder's screen.
If a fish finder has a color screen, the images will vary in color on the screen based on the strength of their reflection. A very dense fish school or one with larger fish will be displayed as a different color than a sparse school of fish. The sea bed and large rocks will also be displayed in another color, as they are even denser that schools of fish.
Understand The Different Types Of Sonar
When buying a portable fish finder, it is vital that you understand the differences between the types of sonar used in fish finders so you can buy the right one for your needs. The most common are Side Scan and Down Scan. Both of these technologies work in the same way, but send out their signals in different patterns.
A Down Scan fish finder directs its signal straight down from the transducer, while a Side Scan model sends its signal out in a fan-like wave. Down Scan models are good because they allow the user to see greater details, such as fish right next to a structure, or even a single fish within a school. They are also more accurate a depths over 40 feet.
For those fishing from the shore or a dock, or in shallow waters, Down Scan fish finders aren't a suitable choice. In shallow waters their powerful waves often reflect back too powerfully and result in an unreadable blur on the screen. Since they only produce readings from straight below the transducer, they won't be very effective for shore and dock fishers.
Side Scan fish finders cover large swathes of water below, to the front, and to the sides of the transducer. Side scan models can read fish and underwater objects anywhere from 50 to 150' in each operational direction. This means that they can very useful for shore and dock fishers. They also don't require a boat to pass over an area to get a reading, so there is no chance of disturbing the fish and spooking them before casting a line in the water. Those who fish in depths of 75 feet or more will notice that Side Scan models begin to lose their effectiveness.
Recently, combination models with both Side Scan and Down Scan technology have been released that offer the best of both worlds. These are more costly than their single scan counterparts, but are the best option if they fall within your budget.