We recently created an infographic explaining why antennas sometimes work and don't work depending on where you live.
Distance is the single most important factor in getting the best OTA channels from your home. Fortunately, this is easy to fix. Use our Availability Report to identify the best antenna for how far away you are from the transmission towers.
Windows in the line-of-sight in the direction of your local channel's transmission towers work best. Our Availability Report will also provide the general direction you need to "aim" your antenna. Outside your windows, be sure there are no major obstructions like trees or other buildings. Attics work great too with Outdoor 60-mile antennas.
There are terrain maps that you can use in order to find out what kind of obstacles you have between you and the antennas you use. You should also find out the location of the transmitter tower and you need to point the antenna to it. This is going to be an extremely important thing to consider when you are setting up your antenna and depending on this, you can decide to place your antenna at a higher location in your home.
Anyone can get an antenna and those who live in uneven terrains can get a stronger type of antenna to overcome any issues with their signal. NoCable.org has maps that give you a great idea on the kind of reception you can get, but 90% of the US population is going to be able to get a lot of channels without having to get cable TV.