mobile

I have a T-Mobile HTC one m8 and just bought a cheap Westinghouse TV. I'm trying to hook my phone up so I can watch videos and live tv on my tv from my phone. I just bought a MHL cable from radio shack for like 40$ and when I hook it up nothing happens. It doesn't even seem to recognize my phone. I switched the tv source to hdmi where it's plugged in and it says no source. I don't have WiFi where I'm at so this is the only way I can connect. I don't understand why it's not working. Is there a certain setting on my phone I should change or did I not buy the right cable? Hopefully someone can point me in the right direction. Thanks