Halakhah sobre Shabat 3:12

It would accordingly seem obvious that one may set a recording device to record a television show on Shabbat, since the Halachah follows Beit Hillel in regard to shevitat keilim (Rambam Hilchot Shabbat 3:2). However, Shabbat 18a records a Beraita (a Tannaitic teaching that does not appear in the Mishnah) that forbids placing wheat in a water mill before Shabbat if it will grind the wheat on Shabbat. As we shall see, this may provide a basis to prohibit recording television broadcasts on Shabbat.