MatCat:
Not quite sure what you mean completely... The idea is to take the single video feed and be able to display it on up to 4 separate video devices.
yes, I realize that, but if the video devices are not designed to operate with a switchable 75 ohm termination resistor (on or off) then your single amp circuit will not be able to drive 4 75 ohm video loads at the same time. Perhaps if you could link to a technical specs of your video devices we could see if they are compatible to 'daisy chain' serial video hookups.
Lefty