CAM-modules are meant to decode certain coding systems whether it is hack or un-hacked. You need a ****** CAM to decode ****** broadcasts. And if you want to decode Seca broadcasts, you will need a Seca CAM. But keep in mind. It will take more than the correct type of CAM alone to view a coded broadcast. So you will not only need a Seca CAM to view a Seca coded broadcast. You will need a valid smart card too.
I would like to take the opportunity to correct a very common mistake. It is not the CAM, nor the card that decodes/unscrambles the movie, documentary or whatever it is you are watching. It is the MPEG decoder in your receiver which takes care of that.