What is a Transducer?

A transducer is attached to your fish finder with a small cable. It takes the electrical signal from your fish finder and turns it into a sound wave and beams it down in the shape of a cone. The wider the cone angle, the wider the coverage.

Each depth transducer contains a piezo ceramic element that works like a loudspeaker and microphone. It converts the electric energy from your fishfinder’s transmitter into a high frequency ultrasound wave. This sound wave travels through the water until it hits an object such as a fish or the sea-bed, which then bounces the wave back to the transducer. The time lapse between transmitting the signal and receiving it back is used to measure the distance to the object.

Quality of Transducer Elements

A poor quality transducer is inefficient at transmitting signal in the water. A weaker signal means poor fish detection, low definition and poor depth capabilities.

Output Wattage

The depth your fishfinder will reach will be affected by water temperature, salinity, frequency, and power output which is measured in Watts. The following general guidelines will give you the maximum depth that can be reached:

100W = 400ft Max Depth

200W = 500ft Max Depth

300W = 600ft Max Depth

600W = 800 - 1200ft Max Depth

1KW = 1800 - 2500ft Max Depth

2KW = 1500 - 4000ft Max Depth

Most recreational fishfinders come with a transducer with a wattage rating that matches the output wattage of the fish finder.

However, when purchasing a transducer separately, make sure the power output of the fish finder unit is less than or equal to the wattage of the transducer, otherwise the transducer may be damaged.

Read about Transducer Frequencies...