The latest flat-panel televisions have multiple inputs for satellite receivers, DVD players, VCR's and cable television. They also have an antenna input for over-the-air broadcasts, and a built-in tuner to allow you to watch local channels. Manufacturers are continually making the depth of flat-panel televisions smaller. That leaves little room for high quality speakers. The solution has been a separate receiver/amplifier and speaker system, capable of reproducing high-definition audio.
Mount an antenna on the roof, or in the attic. Aim it at the nearest high-definition antenna array. If you are not sure where to aim the antenna, you can find that information online.
Connect RG-6 cable to the antenna, and feed it to the television. Connect the other end of the cable to the RF input on the television.
Connect any remaining equipment, using the appropriate cables. For example, if you are connecting a DVD player, you can use an HDMI cable. Connect it between the DVD player and one of the television's HDMI inputs.
If you are using a separate receiver, you can connect a fibre optic cable between the receiver, and the fibre optic audio output connector on the television. There are more involved hookups, but this will get you started, and give you a high-definition picture and sound.
Use your television's remote control to select the antenna input. Follow the instructions in your television's instruction manual to scan for all local channels. Turn on any other equipment you connected, and change the input on the television to match. Check all of the input signals to ensure they are working properly.
An alternate method is to connect all of the video sources to the receiver, and then connect one HDMI cable to the television. This will only work if the receiver has video inputs.
Work with a friend, if you will be working on the roof or in the attic.