I'd love to put my antenna outside, but I'm in an apt. on the second floor, on the side of the building that faces southwest, the complete opposite direction from where the signals are coming.
I'm 30 miles southwest of Chicago, from where the SD and HD signals are beamed. My balcony faces southwest and is right off my living room where my antenna is located. It's an indoor amplified one and gets some, but not all, my local OTA channels. If putting an antenna outside would help, I'd do it, but doing so means having it 5 feet farther away, on the other side of the balcony doors.