The Collaborative International Dictionary of English v.0.48:

LF \LF\ n. (Electronics)
   Low frequency, a term used to refer to radio waves of a
   frequency from 30 to 300 kilohertz. Contrasted to HF, high
   frequency. [Acronym]

   Syn: low frequency.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

LF
    n 1: 30 to 300 kilohertz [syn: low frequency, LF]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

LF
       Line Feed (ASCII)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

LF
       Login Facility (DCE)


The Free On-line Dictionary of Computing (30 December 2018):

LF

   Line Feed