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NCE translator channel screen
Start from your NCE or LPFM station, or an address, and see which reserved-band channels are taken and which deserve a study.
See a promising channel?
Treat this as a first pass, not a clearance, since it does not size the interfering contour of your own translator. RF Navigator performs the complete translator study, with every contour on actual terrain and the FCC exhibits. Nexus Broadcast can also handle the engineering and filing of your window application.
What the check does
- On every reserved-band channel the check poses a single question: does your site fall inside the protected (service) contour belonging to an existing station, a construction permit or a pending application? Applications filed earlier are protected by the cut-off rules at §74.1233, with pending TV channel 6 applications as the only exception. The check does not size the interfering contour your own translator would produce.
- If your site falls within the contour of a station on the same channel or a first-adjacent one, the channel is out, since an interfering contour from your location would overlap that station's (§74.1204(a)). If it falls only within second- or third-adjacent contours, the channel may work if you can show no actual interference would result (§74.1204(d)). Protection for LPFM stations covers only the co-channel and first-adjacent channels.
- Under §74.1204(a), the protected contour is 60 dBu for most stations; Class B stations use 54 dBu, and Class B1 stations in the 92.1-92.5 MHz range use 57 dBu. For directional stations, the contour reflects the station's own antenna pattern in the direction of your site.
- Stations on TV channel 6 are protected by §74.1205, and you get a warning if your site lies within the 47 dBu contour of a channel 6 station. Where a station sits 10.6 MHz or 10.8 MHz (53 or 54 channels) higher than yours, §73.207 spacing applies (§74.1204(g)) when operating at 100 W or more.
- Close to Canada and Mexico, the US-Mexico and US-Canada FM agreements protect foreign stations and allotments, and §74.1235(d) limits apply. If a Mexican allotment covers your site, the channel is out; a Canadian one appears as a warning.
A planning aid. The FCC did not make it, and you need a full engineering study before filing.