Hi Tony.

It definately has an IR sensor. The power button is actually not a button but a smoked plastic lense over the IR sensor. The button is attached to the front panel PCB a little above the button itself and when pressed, it touches a microswitch just below the actual button. In between is the IR sensor. It looks a little like this (poor ANSI art following):

Case:    ,______

         |

         |o anker

         /    |

Button: (   |O| IR Sensor

         \    |

         || <>| Microswitch

         |    |

         |    |

         |    |<-PCB

         |

I just opened the receiver to verify that my initial guess was right, and it really was.

cu,
sven