Antenna systems #1 and #2 Will Not be connected together on to 1 coax.
Antenna systems #1 and #2 are Separate systems all the way to the location of the Tv.
The 2 separate systems Will Be connected to a Remote control A/B antenna switch at the Tv location.
http://www.radioshack.com , #15-1968 , or ,
http://www.mcmelectronics.com , #32-4425 .
Remote control A/B antenna switches are Channel Surfing Friendly , push the button on the hand held remote control , change antenna systems and keep on channel surfing.