I looked around for this information and couldn't find it, so I went ahead and removed the back cover of my Samung HP-S4253 to try and locate the unit's IR sensor. Interestingly enough, the power button is the IR's window. I mounted an RF Extender LED next to the sensor on the power button's PCB, routed the LED's wiring to neatly exit the unit via the TV's source input panel, and what results is a very straightforward and very clean IR LED retrofit.

I'm using the RF Extender for the Harmony 890 remote, in case anyone's curious. I have extended the IR LED wire by routing 16/18 gauge speaker cable behind my wall and terminating both ends with a 1/8" headphone jack at custom wallplates. Along with the 120V AC plug and the single HDMI cable from the TV going directly to the wall, the IR LED plugs in at the wallplate, minimizing wiring clutter behind the wall-mounted flat panel. Cost effective and no-nonsense.

Very cool! I mainly use our DVR when watching TV so I wouldn't need a repeater for the TV, but this is slick. I will probably end up using IR extenders for my other devices once we have a closed cabinet.

I have an LN-S4092D (LCD, not Plasma). I wonder if the IR eye is in the same spot for all Samsungs. Does your set have two IR-looking spots on the bottom right on the front of the set? I'm not sure if they're IR or light sensors.