What is needed to feed off-air tv broadcasts to multiple TVs?

Answer 1

There are two ways to route television signals to several televisions. The first is to use an RF distribution amplifier. These take a feed from an antenna and route it to several outputs. RF co-ax cable is needed to run from the amplifier to each of the televisions. Every television can receive any of the channels available through the antenna.

The other method is to use a receiver such as a digital set top box, a cable or satellite receiver and take the output into a video and audio distribution amplifier. This works well for standard definition video but HDMI distribution amplifiers tend to be expensive and not all televisions will work with all amplifiers. This is due largely to the content protection systems employed in HDMI signals. HDMI of course is the only method of running HD signals in a domestic set up. Note that each television will only display the program that the receiver is sending out so there is not facility for multiple programs from the single source. Cabling for standard definition will be a video co-ax and a pair of audio cables. The co-ax should be a 75 ohm type such as RG59, URM70 or similar. RG59 tends to be the least expensive and for runs below 50 feet or so, is perfectly adequate. HDMI cabling must be bought a a complete cable assembly and prices rocket as the lengths increase.

It's worth thinking carefully about what you want to distribute and how you go about it before investing in cable or hardware.