Cannon
Digi Troll IV Downrigger 
Cannon Digi-Troll(TM) IV
is designed for serious sport fishermen who demand the ultimate in
downrigger technology.
Digi-Troll IV is equipped
with Positive Ion Control which allows you to attract more fish by creating
a positive field of ions around your boat. Adjustable voltage lets you
regulate the strength of the electric field.
Digi-Troll IV's electronic
control lets you program three descent and retrieve speeds and five
different depths, then access them at the touch of a button. Its
cycle-function will jig your bait or lure up and down at a predetermined
depth and time interval—a feature West Coast fishermen find particularly
effective for Pacific salmon.
Digi-Troll IV's expanded
bottom tracking mode is more sensitive than ever before. Digi-Troll follows
the bottom contour, and keeps your weight at a preset distance off the
bottom—even though the contour changes as little as one foot. The unit can
be programmed to minus 50 feet to compensate for blow-back and allow truer
bottom tracking. Digi-Troll IV's Depth Display Screen shows you the true
bottom depth.
Install one Digi-Troll IV
which can be linked to a transducer, and all your Digi-Troll IV's (slaves)
can be linked to bottom tracking through the logic relays. You can run
multiple sets at different depths, say, the master unit at 30 feet off the
bottom, units one and five at 10 feet, and units two and four at 6 feet.
They'll remain that distance from the bottom, no matter how the contour
changes.