インスタ 人気投稿 コツ: It's Not as Difficult as You Think
http://andyldbt333.iamarrows.com/an-introduction-to-insuta-ren-qi-tou-gao-arugorizumu
Even cables with crafted-in repeaters often enable for an exterior power source for being hooked up. This is just a bit additional protection for the signal and may be a good suggestion depending upon the situation