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Black Box Techniques

Chapter I. Catching Fish with Electricity - The Concept


Ever wondered why some boats consistently out fish all the others? Every experienced fisherman has seen it. Two boats using the same lures, same gear, same depth and one will catch most of the fish. The answer may not be as mysterious as it seems. Research in recent years has shown that positive voltage on your downrigger cable can have a major influence on fishing results. As a boat sits in the water, very small

electrical currents are generated as the minerals in the water react with the

different metals on the boat. If the boat is outfitted correctly, a very slight

positive electrical charge will surround the hull. Fish are attracted to this

positive charge. If the boat is set up wrong, an incorrect charge surrounds

the hull and fish will be repelled. Fishermen who learn how to take

advantage of this will significantly improve their catch.


Nearly one hundred years ago, Russian scientists studying fish behavior

learned that most fish have reactions to weak positive and negative electrical

charges in the water.  Some fish, like sharks, will react strongly to very small

electrical fields. Fish are attracted to a positive charge and are repelled by a negative charge. Different species will show varying degrees of electrical reaction. Some of the fish showing the most sensitivity include salmon, kokanee and trout. Natural electrolysis causes electricity to flow from the metal hull parts of your boat to the downrigger cable. If the boat and downrigger are set up right, this will place a positive charge on the downrigger cable which attracts fish. A black box will stabilize this charge at the ideal voltage.


Modern downriggers offer fishermen a big advantage in getting the correct positive electrical charge around their boats. If the downrigger is insulated, natural electrolysis between the stainless steel downrigger cable and the metals of the boat will create a positive charge. The fisherman can then control and stabilize this charge to the ideal voltage by using the Black Box.






























Commercial salmon trollers have used the Black Box technique to increase their profits many thousands of dollars each year by imposing a voltage on their stainless steel lines. By using multiple cables all connected to the Black Box, they can create a complete zone of positive electricity around the boat hull. Downrigger fishermen can create this same field with the Black Box.


The Black Box will significantly improve results when trolling. When used with the nondownrigger transom mount, it can also significantly improve results in rivers and shallow bass areas.  With or without downriggers, it is also effective in  mooching, jigging and still fishing applications. In these instances, some fisherman will use stationary downriggers and others will rely on the transom mount.

Every boat takes on a natural electric charge in the water because of the different metals in contact with the minerals in the water. The zincs on the motor will be positive in charge. This drives the bonded metal parts on the boat to a negative charge. Any unconnected metals like downrigger cable will take on a positive charge.

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