Does anyone know anything about installing an antenna?

depending on the age, you may need to replace the anteena feed line. use coaxial cable such as RG6, RG6 has lower loss at the higher channels where they are parking the HD stations.

you shouls also pull the antenna and clean up all the connections.

First off you should make sure everything is working. Starting at the TV. You said that you did receive over the air broadcasts with a set of rabbit ears. So we know that is working. Next up check the connections. Make sure there is no obvious damage. Next check the cable. Easiest way is using a continuity detector which is built into most multimeter's. This then leaves the antenna. Assuming it is a passive antenna (Not powered) there isn't much that can be wrong. Look for obvious damage to connections on antenna and the antenna itself.

Also as a side note if your rabbit ears are working fine then you really have no reason to be switching to the mast antenna. If your TV is equipped with an Digital (ATSC) Tuner you will be fine with rabbit ears. You can also buy a TV-top converter box.

If the antenna and wire are fairly old it might be best to replace both. You can check and see if the wire connection might be broken at the antenna. You also need to see that the right wire has been used. The antenna on the mast should do at least as well as the rabbit ears, and typically far better. Ask somebody who know a bit about TV antennas what to do. It's not a difficult thing, but there are some tricks you need to know about.

Did you recieve stations before? If so perhaps it's the TV itself. Maybe you need a new antenna. Good Luck..