Digital box or freeveiw box?

I have a telly in my lounge and upstairs bedroom which are both on a sky package. When the digital Switch over happen they were fine. I also have a telly in my kitchen which is has an outside ariel and when the switchover happened stopped working , wold not tune in?. My question is this, in order for it to work again do I need to buy a DIGITAL box for it or a FreeView box I am a littie confused. Thanks in advance