Remember these important points while using the Arduino platform in your future projects.

The most common frequency to transmit IR signals is 38 KHz (Kilo Hertz).

The TSOP1738, TSOP1838 and SM0038 are responsive to, and can detect and decode, IR signals of 38 KHz.

If you want to decode IR signals of a higher frequency than you must use a compatible IR receiver that is responsive to that frequency.

Use the Arduino IR Library written by Ken Shirriff, to work with generic IR components. You must remove the pre-existing IR Remote Library before installing the IR Library by Ken Shirriff.

When using Ken Shirriff's Arduino Library, on an Arduino Uno, only digital I/O Pin 3 can be used for transmitting IR signals. This is because the library internally changes the frequency of pin 3 and utilizes it to send the signals.

The distance up to which an IR LED can transmit will be limited by the power supply. Use an external battery power supply for better range, as Arduino's pins cannot supply the amount of power that an external battery can provide.