Here is a example but not the only example of 75 ohm terminator that is screwed on to any unused output ports of the CM3418 , 8 way distribution amplifier.
http://www.amazon.com/Type-75 Ohm-Te.../dp/B000AAN76Y.
The Tv's Must scan for the Digital Broadcast Tv Channels sometimes named the 'Antenna Channels' or 'Air Channels' in the Tv setup menu because the tV transmissions travel through the air from the transmitting antenna to the receiving antenna.
DO NOT scan for cable Tv channels.
Here is a example but not the only example of a Tv guide on the internet ,
http://www.zap2it.com/tv.