This depends on your building's antenna

For me, I just use my building's centralized antenna and I am getting very good digital reception, but some of the other forummers here have reported this did not work for them and they had to buy external antennas.

Just test the centralized building one first, since that is the cheapest method cos you would only need an RF cable to connect to the wall. I only spent RM6 for one in Ace Hardware.