Rigging a Fish Finder - Part 2: Battery Power

You have found the perfect fish finder, and you are ready to start cutting, drilling and ultimately, fishing. Well, before you can do any of that, you must decide how to power the thing. You basically have two choices...one big rechargeable battery, or a bunch of small rechargeable batteries. These choices lead to various considerations:

• How much voltage does my fish finder need to operate?
• How many amp-hours (hours of use) will the batteries deliver?
• How much space and access do I have for mounting the power source?
• How much do I want to spend?

Probably the easiest way to go is to use rechargeable AA batteries that you can buy just about anywhere. Most of the fish finders that are appropriate for use on a kayak are designed for 12 volt marine batteries, and will operate within a range of 10 - 15 volts, so an array of eight AA batteries should work perfectly. Eight AA rechargeable batteries will typically deliver a little over 10 volts to the fish finder (usually about 1.3 volts per rechargeable battery, as opposed to 1.5 volts per carbon or alkaline battery). In fact, the fish finder I use on my kayaks requires at least 10 volts to operate, and with 8 AA batteries I am getting about 11 volts. As far as running time is concerned, my fish finder has a current drain of 180 milliamps (ma) every hour. Since I am using 2500 ma batteries, in "theory" I should get 13 hours of use from my fish finder before having to recharge the batteries. In reality, after about 4 - 6 hours the voltage output will drop below where the fish finder will operate. This setup is the smallest and lightest way to go, can usually be purchased (8 batteries and charger) for $20 - $30, but will give the shortest running time.

You can also use one larger, rechargeable battery for your fish finder kayak installation. There are many options, from home alarm panel backup batteries, to deer hunting auto-feeder batteries, to general purpose hobby batteries. Cabelas has a popular rechargeable battery that delivers 12 volts and 8 amps. The primary benefit of a larger battery is a much longer running time between charges. The main drawback is the larger size and weight of the battery. The Cabelas battery and charger is $30, which is an average price.

Now that you are all powered up, don't forget to check back for the next installment: mounting options.

Good Paddling

The Kayak Sportsman

Rigging a Fish Finder - Part 1: Choosing the Right Model

What should you look for in a fish / depth finder for a kayak? Well, the most obvious feature is portability. You need to find a unit that is small enough to carry or mount on a kayak, is powered by a voltage and amp range that can be served by a reasonably sized battery setup, and has enough features to make it useful. You also need to decide how big and how colorful you want the display screen, and what options you have for mounting the transducer. Of course, you have to find all of the above in a fish / depth finder that fits your budget.

There are a few "true" portable fish / depth finders on the market, with battery and transducer options designed for self-contained use, with no real installation needed. One popular series of portable fish finders is the "SmartCast" series by Humminbird. Eagle (a subsidiary of Lowrance) also makes a few models of portable fish finders. Although their performance can be variable, portable models are well suited for those who don't like the idea of making permanent alterations to their kayak.

Garmin, Humminbird and Lowrance / Eagle are probably the four most widely used brands of compact and portable fish finders on kayaks. My suggestion is to do some research on their websites to compare features (you will find that there is a great deal of overlap between Lowrance and its Eagle products) and then look for user reviews. A great place for reviews is Amazon. A quick search on Amazon finds quite a few models available, with plenty of customer reviews for most of them. The prices on Amazon are also pretty good, but when you narrow it down to one or two models, you can verify the best price with a Google Shopping search. For example, here is a quick Google Shopping search for an Eagle Cuda 300 fish finder, sorted by lowest price first.

Since this series will be following the experience of KayakDoc, you will see in his pictures that he chose a Lowrance X50 DS. Remember, there is no right or wrong choice, only the choice that works best for you. The good thing is that since the X50 has a similar general shape, base, cable and transducer to many of the models most commonly mounted in kayaks, the experience will be similar for most of you.

Good luck in your search. Check back for the next installment: battery power.

Good Paddling

The Kayak Sportsman

Rigging a Fish Finder - Introduction

OK, so you have decided to take your kayak fishing to the next level. Your kayak has rod holders, and places for stowing gear, bait, and the fish you catch. You even have a handheld GPS in your pocket (hopefully on a leash!). And now all you need to complete your ultimate kayak fishing rig is a fish / depth finder. Not too long ago this would have sounded crazy, but as the sport of kayak fishing has matured, so have the options for boat customization. It should come as no surprise that small, battery-powered fish finders eventually found their way onto kayaks. In fact. some manufacturers even make fishing kayaks with dedicated mounting and stowage options for fish finders.

I have been using a fish / depth finder on two of my boats for several years now. So when one of my readers shared with me the story (and pictures) of how they mounted and rigged one to their kayak, I asked him to let me share his experience with all of you. This will be a multi-part series of blog posts that combines some tips and DIY how-to, links to other sites and references, and the pictures from faithful blog reader, KayakDoc.

Before you decide to run out and buy a fish finder for your kayak, you have to understand that rigging a kayak is quite serious stuff. If you have never drilled a hole in your kayak's hull, you must keep in mind that installing accessories on your kayak may:

• Void the warranty of your kayak
• Damage your kayak beyond repair
• Compromise the structural integrity of your kayak
• Allow your kayak to take on water
• Make your kayak dangerous and unsafe to operate

In other words...please be sure you are comfortable working with tools and adhesives, especially as they pertain to marine applications. Do not attempt this or any modification to your kayak if you do not have the skills and experience necessary to undertake the work described. If you decide to modify your kayak in any way, make sure you read and follow the safety instructions for all tools and supplies you will be using, and use the appropriate safety equipment (eye protection, dust mask, etc.). The blog posts that follow are meant for informational and educational purposes. If you decide to use this information in any way, you assume any and all risks.

Stay tuned for Part 1 - "Selecting a Fish / Depth Finder"

Good Paddling

The Kayak Sportsman