Is a husband Islamically entitled to refuse to buy a television set for the house, fearing it might be used in ways displeasing to Allah, knowing that his wife does not listen to music and is willing to purchase it with her own money?

There is no harm in acquiring devices that can be used for permissible purposes, including television, if the husband knows that his wife will limit its use to what is permissible. However, if he predominantly believes that it will be used for impermissible things, then it is not permissible for him to acquire it, because predominant belief takes the place of certainty, and the husband is a guardian in his home and responsible for those under his care.