I be skeptical that this item would not work . I have purchase a `` cheaper '' item at a big box retailer , and do nothing . however , this box work excellent . I have cable into my house . I have 2 tv 's that have digital cable box , which be always boarder line on quality signal -lrb- some channel would look scrabble sometimes , not often -rrb- . I have 3 tv 's which be hd , that do not have box -lrb- they get the 19 free hd channel -rrb- and these hd channel would scrabble or have delay ... however , install the booster and notice a immediate improvement . all my channel look brighter and 100 % perfect . in fact , on my tv 's , where I do not have the digital cable box , I pick up 2 more hd channel , now , 21 -lrb- free -rrb- , that I do not get before ! that be how weak my signal be before ; the tuner do not even find the channel . I wish there be a 6 channel . I have output 1 and 2 to my digital cable box , output 3 to another tv , and I split output 4 into 3 other tv 's . all channel work great ! \*\*\* note that you will need a piece of cable to run from the power supply to the signal booster \*\*\* do not come with .