In the analog days, many of the stations operated on low-VHF channels at very robust power levels. Low-VHF-bends very well over mountains, but unfortunately is mostly unsuited for digital operation due to problems with noise interference. As a result, most TV stations moved to UHF channels or the high-VHF territory. UHF signals bend very little making them mostly useless in mountainous areas. High VHF bends a bit better, but the stations are limited in transmitting power due to the requirement to avoid interfering with broadcasters n adjacent markets.
The bottom line is that there are little to no signals making it into your valley.
Visit
www.slingbox.com to learn how to access a remotely installed antenna system via the internet.