G'day guys,I bought a HDS 7 with the standard 200/50 transducer last year and was only getting about 200 fathoms out of it.I rang the guys at Navico who were great and super helpfull.The sounders are all set up with a generic input for the transducer.If you go to the menu on the sonar set up and press it twice there will be a function that says transducer,click on this and it will have all the different transducer models.On the back of the plug where the transducer plugs into the sounder there is a tag with a code.I matched mine up and was getting 400 fathoms.Other than this the sounder has been great.Also had a mate look at it and if you adjust the sensitivity it makes a big difference picking up bait schools and fish.A 1kw transducer is $1340,too much cash for me at the moment.Good luck.