I came across this article, and I intend on building this antenna. Keep in mind, this antenna is for picking up UHF signals, which digital TV now uses. Growing up in the 70's, UHF was mostly for public access channels like PBS.
TV Antenna Plans
The OTA signals you can pick up vary from area to area, so here is a web site that can help you determine which stations are local to your area.
Here are a few YouTube videos for building a DB4 antenna: