FM on AM translator window closes.. advice for LPFM stations

For the past 9 months, the FCC has provided an opportunity for FM translators including the many that were applied for in the 2003 "Great Translator Invasion" window to be moved up to 250 miles from their current location in order to rebroadcast an AM station as part of Commissioner Ajit Pai's "AM Revitalization" program.

Based on all of the FM Translator modification and "modify CP applications" filed, 144 of them specified facilities that either resulted in or maintained a §73.807 short spacing to an LPFM station.  

View the complete application list here(opens new window)

This is possible because of the differences in how LPFM stations are required to protect other stations as opposed to how FM translators are required to protect other stations.  

LPFM stations protect FM translators using a standard distance separation.  FM translators are divided into three "sub-classes" based on the average service contour size based on 8 radials into a non-directional antennas (similar to how we determine service contour size for LPFM stations).  There are then minimum distance separation requirements for co-channel, first and second adjacent channels.  

FM Translators use the contour overlap method to protect LPFM stations. FM translators only need to assure that their predicted interference contour does not overlap into a LPFM station's protected service contour.  Translators are allowed to use directional antennas to reduce radiation towards a neighboring LPFM station in order to prevent the contour overlap.  FM translators are only required to protect LPFM stations on co-channel and first-adjacent channels.   No second-adjacent channel separation protection is required. 

Due to one of the two provisions that surivived the former Radio Broadcast Preservation Act when it was superceded by the Local Community Radio Act was a requirement that some form of second adjacent channel protection was still required by LPFM stations towards other broadcast stations.  Language in the LCRA premits this second adjacent short spacing to be waived. 

If the translator short-spaces an LPFM under §73.807, the LPFM is not obligated to move.  The short spacing will only result in LPFM station not being allowed to move to a new location closer to the translator.   

One other thing to keep in mind is that translators are permitted to also "come inside" the interfering contours of other FM translators. When that happens, that will impact the ability of one translator to not be able to move.   However, unlike LPFM, translators can use directional antennas to protect other translators.

Whether the LPFM station will receive interference by a translator that is moved under the translator rules where there is no contour overlap will depend on various factors including terrain and whether the translator facility is constructed properly under the terms of the construction permit.  The method that the FCC uses to determine service and interfering contours is a very archaic method that is based on the terrain between 2 and 10 miles (3~16 km) from the transmitting site.  While this method is fairly efficient for determining coverage of high powered stations, it is very ineffective for lower powered stations like FM translators and LPFM stations.  LPFM stations may still receive interference and degradation, especially in the fringe areas outside the protected contour. 

LPFM stations that are already constructed, licensed and on the air when the FM translator modification application was filed may be able to seek additional protection under §74.1203(a)(3) of the rules.  Under this rule, an authorized FM translator will not be permitted to continue to operate if it causes interference to:

The direct reception by the public of the off-the-air signals of any authorized broadcast station including TV Channel 6 stations, Class D (secondary) noncommercial educational FM stations, and previously authorized and operating FM translators and FM booster stations. Interference will be considered to occur whenever reception of a regularly used signal is impaired by the signals radiated by the FM translator or booster station, regardless of the quality of such reception, the strength of the signal so used, or the channel on which the protected signal is transmitted.

This rule pre-dates the creation of the LPFM service which is why LPFM is not spelled out in the rule.  It is REC's interpretation of the rule that LPFM would fall under the blanket phrase of "any authorized broadcast station".  The FCC has made no decision on that however this rule is currently being tested as of the date of writing. The common application of this rule, mainly by full service stations is if the LPFM station has at least one bona-fide listener within the protected contour of the translator and that listener is willing to provide a public statement that will go on the public record that they listen to your LPFM station from within the protected contour of the proposed LPFM station. These listeners must be "disinterested" parties.  This means the listeners can not be staff or volunteers at the station or any of their family members.  This objection can be filed at the time the FM translator files their license to cover once construction is completed.   REC strongly recommends you obtain the services of a qualified broadcast attorney to file with the §73.1203 objection.  Your attorney may get technical exhibits from REC.  REC has a list of attorneys on our Recommendations page. 

For now, if you have a new neighbor on your channel, please remain vigilant and assure the translator is built in accordance to their construction permit including the directional pattern and know that you may have grounds for a complaint if the translator is not built per the permit or otherwise causes interference within your LPFM station's protected contour and in some limited cases, outside your contour.   Remember too, we share spectrum with translators.  If you are considering some form of action towards a nearby translator, please contact REC first and let a second set of eyes look at your situation.  Advice is always free at REC (if you use the tip jar, that's your choice).