Sonic ,
FTA = Free To Air = free channels in the sky that the FTA receiver can alllow to pickup. DirectTV / Dishnetwork are needed to pay for in order to get those channels so ...
FTA system need to have a dish of at least 30 inches. It needs to have its own receiver and doesn't need a bin like the other
DTV/Dish because it is FREE !!! and the serial cable is only needed when your receiver need a special update data from its manufactory { ie your receiver is Coolsat; manufactoty Coolsat has update then go to its website to download and update but it is very rarely to happen }
g00d luck and Welcome to FTA World ...
remember ... FTA is g00d but it is a different animal compared with the other DTV/Dish ... You will learn to love it or hate it !!!

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