Here are top and bottom views of the TMR-IF33 infrared transmitter. The transmitter base holds a pivoting mast containing an IR LED array behind a dark filter/lens.

The transmitter has a stereo audio mini-jack input, stereo RCA jack inputs, and a 9V DC input jack. On the bottom there is a switch for normal/surround sound.

On the back you can see some keyed mounting holes for optional wall-mounting ofthe transmitter.

We'll take this transmitter apart first...