eLMS: Second and third-adjacent channel short-spacing/overlap

eLMS has added two new report runs that will check filed applications to determine if either:

  • For LPFM applications with engineering, whether there is a §73.807 short-spaced second-adjacent channel facility record; or
  • For FM Translator applications with engineering, whether there is prohibited overlap of another facility record on second or third adjacent channels thus requiring a technical study and a waiver request.

Two new tables have been added to eLMS to support this data:

fx_seco will include the details on second and third-adjacent channel overlapping facilities.

lpfm_seco will include the details on second-adjacent channel short spaced facilities.

Please note that for applications filed on or before July 5, 2024, the data will include all short-spacings and overlaps as of July 5, 2024.  Going forward, eLMS will run these two reports overnight and data included will only include short-spaced or overlapped facilities at the time of the run.  Subsequent short-spaced and overlapping relationships will not be included.  

Data items collected in these tables include:

  • Details on each facility so they can be referenced to and from other eLMS tables;
  • The type of channel adjacency (for FM Translators);
  • The required §73.807 distance (for LPFM);
  • The distance between both facilities;
  • The arriving service contour at the short-spaced or overlapped secondary facility;
  • Determination of overlap; and
  • The distance of the "overlap zone", which is the area surrounding the LPFM or FM Translator facility's antenna that must be protected using the 40 dB undesired to desired ratio method.


Monday, July 8, 2024
Systems affected: 
Issue type: