There are two kind of echosounders available for the NavNet systems. DFF1 and DFF3. DFF1 has a transmission effect of 600W and 1 kW while the more powerfull DFF3 has an effect of 1,2 or 3 kW.

Both the DFF1 and DFF3 can be directly connected to your MDF or Black Blox via a simpel ethernet cable.