Emerson LC320EM2 and Sotek HD Amplified Digital TV Antenna

[TNRVER]

Recently purchased the Sotek HD Amplified Digital TV Antenna for use in our Motorhome to get local channels while traveling.  Installed it on our Emerson LC320EM2, following the instructions, by plugging the power cord into the USB port on the TV since the power cord was too short to reach the wall plug.  After about an hour, the TV went black and is not getting power.  I am a novice at tv repair and would appreciate any and all suggestions of things to try.  Thank you.