Teleflex TFXIDF Operation Manual page 9

Grayscale: The grayscale feature on the IDF will identify the 1) size of a target,
2) presence of baitfish 3) bottom content and 4) fish on the edge of the cone
angle. Here, a fish at 16' is moving either in or out of the transducer cone,
while another fish is directly under the transducer cone near 17'.
SUPPRESSION
Dead Zone: Any and all sonar devices will have a dead zone in certain
instances, such as sharp drop offs. Anything below the shallowest return in the
cone cannot be seen.
USING THE IDF SERIES
SUPPRESSION
SIGNAL INTERPRETATION
Fish at 17' and either baitfish or
larger fish at edge of cone at 16'.
A sloping bottom causes a "Dead Zone".
In this illustration, the Dead Zone starts
at 20' and continues to 26'
20'
26'
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