Depends on how you plan to connect the two antennas coax to your system. If you run two separate coax, connect one to your TV and the other to a "tuner", and the tuner to the TV by HDMI, should work without problems. But if you plan to combine the antennas with one coax down lead you may run into a couple of programs. The signal from the original antenna may be weaker depending on how you combine it. And the TV may see the same two freqs as interference and be unwatchable. Unless you can delete one from your channel list. Channel Master sells a combiner you may be interested in.......
The Channel Master JOINtenna combines coaxial inputs from two individual outdoor TV antennas allowing for the distribution of two antennas on a single coaxial cable.
www.channelmaster.com