If your TV antenna is good quality and was installed by a professional, you can expect it to last between 10 and 20 years without needing repair or replacement. This can vary based on your geographic location, weather conditions, and antenna location. 

Yes, in general, raising your TV antenna will improve your reception. Besides raising the location of your antenna, you should try putting it by a window. In fact, you can have the same antenna but get double the channels or more if it's in the best location. The highest spot to put a TV antenna will be on your roof, and the tallest type of outdoor antenna is a tower.

Annual checks for damage or misalignment and ensuring clean connections.

Before investing in a TV antenna repair, there are a few steps you can take to help boost your signal quality. Removing obstacles like tree branches can help improve your signal strength. Along the same line, moving an indoor antenna away from obstacles can also help. These should be near a window, as high as possible. If these steps don’t work, speak with a TV antenna technician about a signal amplifier to help boost your signal even further.