Two-Way Radio Narrowbanding for the Locomotive Industry


The FCC mandates that all commercial two-way radios must be narrowband (12 kHz channel spacing) by January 1, 2013. But for the railroad industry, that deadline came and went much earlier. Led by the American Association of Railroads, the industry voluntarily set a July 2010 deadline for all locomotives to be narrowband capable. This early deadline allowed the industry time to identify any “bugs in the system” and to catch any locomotives that it might have missed.

As it turns out, the early deadline proved beneficial. The FCC mandate is intended to increase the number of usable voice channels on two-way radios by cutting the bandwidth and spacing in half, resulting in 12.5 kHz channels spaced at 7.5 kHz, rather than the current 25 kHz width spaced at 15 kHz. In practice, however, railroad pros found the narrowband emissions of two channels may overlap and cause interference. To remedy the situation, AAR officials recommend avoiding the use of the 7.5 kHz separation or use of the interstitial channels for narrowband.

If you’re a railroad industry professional and have yet to migrate your two-way radios to a narrowband or narrowband-capable system, know that any wideband applications or modifications are no longer accepted as of January 1, 2011. All new applications or modifications must be for narrowband or very narrowband (6.25 kHz / 4800 bps digital signals). Wideband operation will not be permitted after January 1, 2013.

If your two-way radios are capable of narrowband analog operation, there’s no need to replace them just yet. However, be aware that railroad professionals are adding a leading zero to the narrowband channel number in order to differentiate it from a wideband channel on the same frequency. For instance, channel. 52 is wideband, whereas channel 052 is narrowband. If your two-way radios are unable to display leading zeros, you may want to replace them.

Very narrowband operation will be mandated by the FCC in the future, but it appears that the deadline may be as far ten years away. So, if your radios are narrowband-capable but not very narrowband-capable, there is no big rush yet. However, if you’re purchasing new two-radio systems anyway, why not go ahead and get very narrowband-capable models?‘s specialists are familiar with the communications nuances of many industries, including the railroad industry. Search our online inventory or contact us at 1-888-560-0758 or via our convenient online email form to speak with a specialist today.

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