The local Tv stations/channels are Very Strong Signal Strength at your location.
Aim a ANT751 antenna at about 357 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Recommend ->Do Not<- use Any Type Or Kind of antenna system amplifier.
The Strong local Tv stations will most likely overload a amplifier and be the cause of reception problems.
If you will like to 'Test' reception of the L.A. stations and receive the local stations , aim the VU190 at the L.A. stations.
Any cable delivered services , cable tv , cable internet , cable phone , Must Be on separate coax from the coaxes that are used for the antenna system.