TZ Touch system Speed through water transducer

[hornloaded]

I'm try to figure out what would be the correct transducer to connect to my system for Speed through water? I have a TZTBB and a TZT9.
Wasn't sure If I should get a Airmar NMEA2000 unit or something that connect directly to one of the MDF. 54' pilothouse trawler
Thanks
DD

 

[Quitsa]

I used an Airmar DST800 Smart Sensor NMEA 2000 transducer. It has the advantage of providing a backup depth data source that is especially good in shallower water being 235Hz. It also is easy to pull it out of the housing with the boat in the water to clean any fouling (it comes with a plug to block the hole).

It is quite accurate once calibrated with a two way reciprocal run using the GPS SOG.