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Black Box Techniques

These photos show the Black Box in a typical "Natural" voltage position and an "Imposed" position. In the left photo the lever is in the "up" position and the Box shows a natural reading of .768 volts. In the right photo the lever has been moved to the "down" position and the dial has been adjusted to an imposed setting of .608 volts. In most instances you will be lowering the natural voltage to get the reading you want. From time to time while you are fishing, it is a good practice to switch the mode switch to the natural reading position. If you get a normal natural reading, this tells you that all your connections are working. If you are running multiple downriggers on one Black Box, you should make this test on each downrigger with one in the water at a time. If you get a zero natural reading, the first thing to check is the contact sleeve riding on the downrigger cable. Sometimes scum will insulate the contact. You can usually get it working by wiggling or sliding it back and forth on the cable.

Chapter IV. Black Box Operation and Recommended Voltages


















1.  Plug in the power to the Black Box. Be sure the Black Box switch is turned to the "off" position (all the way counter clockwise).

2.  Be sure the metal contact sleeve is in place on the downrigger wire and connected to the Black Box.

3.  Drop the downrigger to fishing depth or at least a few feet under the surface.

4.  Turn the knob to the "on" position. Put the mode switch in the Natural Voltage position. If you get a normal voltage reading (.7 to .8), you will know all wires and connections are functioning correctly. If for example, you get a zero reading, you will know something is wrong. To apply a selected voltage to the downrigger cable, flip the switch to the Applied Voltage position. You can then turn the dial to set any reading you want from zero to one volt.


Recommended Voltages

There has been a great deal of work done on the correct downrigger cable voltages for salmon, trout, kokanee, bass, laketrout and other species. The following table should be used as a suggested starting point. You may find other voltages that work better.


Species Voltage

Chinook (KIng) Salmon .600 volts

Coho (Silver) Salmon .650 volts

Sockeye Salmon .750 volts

Kokanee Salmon .650 volts

Halibut .450 volts *

Laketrout (Mackinaw) .650 volts

Rainbow & Brown Trout .650 volts

Cutthroat Trout .650 volts

Black Bass .750 volts *

Sharks .400 volts *

Striped Bass .650 volts *

Sturgeon .500 volts *

Catfish .500 volts *


* Further research may change this recommendation.






















The Black Box is very effective in improving results when trolling. It should be connected to all the downriggers on the boat so it provides a uniform positive charge completely around the hull. There is a zone of fish attraction created at the downrigger cables. The fish will come to the cable. Often, results will be best by using a very short drop back leader between the downrigger release and the lure or bait.























When you are trolling with the Black Box, the electric attraction zone is set up between the positively charged downrigger cable and the negatively charged outdrive and other metal boat parts in contact with the water.

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