third adjacent channel interference

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In part one of our report on the FCC’s recent actions on LPFM issues, we wrote about the FCC decisions about what to do with pending FM translator applications that may have an impact on LPFM availability. In this part two, we discuss the Commission’s separate order addressing the provisions of the Local Community Radio Act eliminating third-adjacent channel spacing restrictions between LPFM stations and full-power stations and otherwise modifying the interference protection standards that apply to these stations.  In a third part of this series, to be published soon, we will report on the proposals for changes in the LPFM service rules.

The impetus driving Congress in its adoption of the Local Community Radio Act ("LCRA") was the desire of LP FM advocates for the elimination of all third-adjacent channel protections between LPFMs and full-power FM stations. While the statutory changes mean that LPFM stations do not need to be spaced at any particular distance from third-adjacent channel FM stations, the changes do not completely eliminate all interference protections afforded to full-power stations. In fact, the LCRA sets up a very extensive scheme where LPFM stations must work to resolve any interference that is created to adjacent channel full-power station. The Commission set forth its reading of the statutory requirements, summarized below, and asked for public comment on that interpretation.Continue Reading FCC Clarifies Rules for LPFM – Part 2 – Interference to Full Power FM Stations

The Local Community Radio Act has been pending in Congress, ready to be approved for many months, but held up by the Senate.  This weekend, as the Congressional term was drawing to a close, both the House and the Senate approved a bill modifying the interference standards for Low Power FM radio stations, opening the possibility that more channels will be available for LPFM use when the next window for filing new LPFM applications opens. However, this bill is substantially modified from the LPFM bill that was just passed by the House of Representatives earlier this year (see our summary of the House version of the bill). The NAB has been working with the LPFM advocates to adopt a bill with substantially more protections for full-power stations, while still allowing LPFMs to locate on channels third adjacent to full power stations. The bill passed by Congress and soon to be signed by the President makes substantial changes to the original House version, and seemingly provides many such protections. Specifically, the final legislation is different from the old bill in many ways including:

  • It does away with all the introductory language in the original House bill that contained many Congressional findings about the value of LPFM stations, language that could have been used to justify FCC actions in the future that would be unfavorable to the interests of full-power stations. 
  • It specifically forbids the FCC from amending the distance requirements between LPFM and full-power stations for first and second adjacent channel operations.  It does allow for waivers of these separations, but requires LPFMs to cease operations if complaints of interference to a full-power station are received.
  • It makes clear that LPFM stations are secondary to full power stations, both as they currently exist and as they may be modified in the future. 
  • The law specifically requires that the FCC treat LPFM and FM translators and FM boosters as being equal in status, and secondary to full-power stations (both existing and modified full-power stations) – thus seemingly ending some of the LPFM proposals that would allow LPFM stations to preempt existing FM translators.
  • For LPFMs that are located at less than the full distance from a full-power station set out by the LPFM rules, even on a third adjacent channel, the LPFM must provide the same protections that translators give to other stations under Section 74.1203, which includes the requirement that a new secondary station (like a translator or LPFM) cease operations if it interferes with the reception of any regularly used FM signal (even if the signal is outside of the existing station’s primary service contour)
  • The bill adds a provision to protect stations in certain densely populated states (principally if not exclusively New Jersey) by imposing the translator interference rules on LPFM stations (seemingly the same provision as provided for stations in other states when the LPFM is operated at less than the current spacings. 

This bill does contain some provisions that are not entirely clear, and in some cases, provisions that seem a bit contradictory. These issues will no doubt be sorted out by the FCC, and potentially by Congress itself, in the future. Continue Reading Bill Changing LPFM Spacings But Protecting FM Stations Passes Congress – After NAB Assures More Protections to Broadcasters

In the last week, several new LPFM issues have arisen – one a Congressional push to authorize more of these stations by ignoring third adjacent channel interference to full power stations, and another involving complaints to the FCC about LPFM stations being forced to change channels or cease operation because of interference from changes made by full power stations. The latter issue has apparently arisen in the context of stations taking advantage of the FCC’s rules which made it easier to effectuate changes in the cities of license of FM stations (see our summary of the rule changes here), causing more movement of such stations. Both of these issues could present issues for FM broadcasters. 

The Congressional action was initiated by the introduction of legislation in both the House and the Senate that would eliminate third adjacent channel protections that full power stations have from LPFMs. Those protections have been the subject of controversy since the FCC authorized the LPFM service.  LPFM advocates have contended that the interference protections are unnecessary, as most FM receivers should be able to distinguish between stations on third adjacent channels. The NAB contends that the protections are needed as there are still many radios that would be affected by that interference. Full power stations, except for those authorized at short-spacings prior to 1964, are protected from third adjacent channel interference from each other. Competing engineering studies have been done, the FCC has not acted on this question (and in fact Congress had prohibited such action years ago).  But now, some feel that the time for some liberalization of the rules is in order.Continue Reading LPFM v. FM – More Stations Coming?