I have two dome cameras I am trying to connect to a dedicated TV (acting as a monitor). I have tried every which way and am running out of ideas. Using adapters I have connected both via the RCA video input and each camera works fine. I am trying to connect a switching solution to switch between the two cameras. The TV has only one composite video input and obviously a CATV F input. I have tried a multi-channel modulator, a video selector switch, two modulators output to different channels and combined, everything. What I don't understand is it appears as if the cameras are shorting each other out. If I have one connected to the video input and connect the other to a modulator, the minute I connect the modulator to the TV, the video blanks out and it sparks as the outer part of the connector (ground) makes contact. Any time both cameras are connected simultaneously through any type of apparatus this happens. PLEASE HELP!