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Citizens Radio ReviewCommunity radio and low-power FM, explained

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Desk 03 · LPFM Rules Made Simple

LPFM rules made simple

The FCC’s LPFM rulebook in plain English: 100 watts, 30 metre antennas, the point system, adjacent-channel protections and the 10 kHz offsets.

Open federal rulebook beside a hand drawn diagram of two radio towers and a ruler marking the distance between their channels on a desk

Nothing scares volunteers away from LPFM faster than the rulebook. This desk takes the rules one family at a time and translates them: how far a 100-watt signal actually carries, why the FCC scores applicants with points, what first-adjacent and second-adjacent protection mean for a channel search, and how a station can end up licensed at an odd 10 kHz offset from the familiar dial numbers.

We keep one rule for ourselves: every page in this desk states the rule first, then the reason it exists, then what it changes for a real group with a real transmitter. The application window guide shows the rules under deadline pressure, and the Emergency Alert System guide covers the one rulebook volunteers ask about most.

In this desk

  1. A printed tartan swatch book open on a wooden table beside a measuring tape and a pencil, with soft window light falling across the cloth from the left.

    Reading the Scottish Tartan Register

    The Scottish Register of Tartans is the national collection of tartan records, kept by the National Records of Scotland.

  2. A village hall table in soft morning light, covered with a white cloth, holding five evenly sized runner beans on a white plate and a vase of seven sweet peas, with a handwritten class number card in front.

    Local Produce Show: Entry, Bench, and Flower Prep

    Local produce shows are open to amateur gardeners who grow their own.

  3. A wooden church pew in late morning light, a worn hymnal open on the seat with a ribbon marker, and a printed order of service resting beside it.

    What Lutherans Believe and How Worship Works

    Lutherans teach that salvation comes by grace alone, received through faith, not earned by good works.

  4. Coaxial feedline running up a short mast toward a folded dipole FM antenna with a small transmitter building and a pickup truck below at dusk

    Why Your 100 Watts Does Not Reach the Whole County

    The license says 100 watts, the listener hears a radius, and between the two sits a chain of components each quietly taking its share of the signal.

  5. Small FM broadcast antenna mounted on a mast above a residential rooftop with neighboring houses and gardens visible in flat afternoon light

    Living Near a Community FM Transmitter: Field Strength and Limits

    A 100-watt antenna on a rooftop raises a fair question in the houses around it, and the answer is a matter of physics, reference levels and honest measurement.

  6. Clipboard with a licensing checklist on a broadcast console beside a stack of music CDs and a film festival program in a volunteer office

    Clearing Rights Before You Broadcast or Screen: a Volunteer Media Checklist

    Volunteer media ask the same question in every format, radio or film: what rights does the room or the signal require, and who sells them?

  7. Small town viewed from a water tower at golden hour with rooftops and playing fields spread below the antenna of a community radio station

    What 100 watts buys on the FM dial

    One hundred watts is a light bulb with a license, and the size of its footprint is not an accident but the central promise of the low-power service.

  8. Scored application worksheet with tally marks beside a framed community charter and a small scale model of a radio mast on a meeting room table

    The FCC point system made simple

    The point system is the FCC’s answer to a simple question: when several communities’ groups chase one frequency, which of them is most the community’s own?

  9. Engineering sketch of concentric protection circles around two broadcast towers with a compass, protractor and penciled frequency notes on drafting paper

    Protections, offsets and shared dial space

    The FM band is a geometry problem: every new signal must prove it will not hurt its neighbors, and the FCC’s spacing rules decide where a 100-watt station may legally stand.

Two neighbouring desks extend this one: Stations Near You and Start a Station. The magazine’s method is stated on the editorial policy page.