sparkfun/SIK-Guide-Code — pull request #1 by webbj74 (2012-12-25 19:39:18+00:00)
Title: Replaces occurences of "a LED" with "an LED" for consistency.

Most online dictionaries (Merriam-Webster, Wiktionary, et al.) treat LED as an abbreviation/initialism rather than an acronym, so "an" seems to be the best choice.

References:
* http://www.merriam-webster.com/dictionary/led
* http://en.wiktionary.org/wiki/LED
* http://www.thefreedictionary.com/LED
* http://wiki.answers.com/Q/Is_it_a_LED_or_an_LED&src=ansTT