Are TV IR remote control receiver modules frequency selective? I know that remote control systems use PWM and the pulses are decoded by a microprocessor. What I would like to know is whether the module that functions as the IR photosensor, amplifier and pulse shaper is usually tuned to a particular carrier frequency so that they are not all interchangeable (aside from things like pin-out, pulse polarity, etc.).
If this is so, how sharply are they tuned? Is it likely that a receiver tuned to, say 38 kHz, will respond well to 36 or 40 kHz emissions?