Listed below are standard frequencies used by railroads in the United States. Most of the same frequencies are be used for cross-border operations with Canada. The American Association of Railroads (AAR) has assigned channel numbers to each standard voice radio frequency.
Such channel numbers are used with railroad radios and are commonly referred to by field personnel. Locomotive radios are able to select individual transmit and receive frequencies as needed. Sometimes this can be heard as "Go to 20-90". Standard practice is simplex operations, with the same channel number (i.e., 3636). A common channel for Union Pacific is channel 020, and may be heard on the radio as "go to Channel 20." Railroads on the radio still use the old channel number as opposed to the new numbers, where appropriate (i.e., "20" vs saying "020").
The AAR standard for digital voice radio uses the Kenwood/ICOM NXDN/Nexedge digital format in 7.5 kHz channel spacing. There is no mandate to use digital, but those locomotives or operations that are required to interchange with other railroads must use NXDN, if digital radio is used.
Regional or smaller/tourist railroads have been known to use channels or trunked radio systems outside of the AAR plan. In addition some small operations even use DMR or other modes or systems for internal communications. If interchanging with another railroad, the AAR standard will typically be used.
Amtrak/passenger trains outside of their own rail lines can be found on the host railroad's radio channels. Station operations may or may not be on a separate channel. Trains from another railroad company operating on another railroad will be found on the host railroads channels (i.e., a Norfolk Southern train detouring on CSX).
Railroad radio operations are additionally found in each states railroad section.
Frequencies
Railroad Operations
AAR 001-097
These channels are part of the original AAR band plan, and are widely used in the United States. After the narrowband mandate, AAR relabeled the channels with a 0 (zero) to indicate that the channel is now narrowband. Channel 24 (25KHz. wide) became 024 (12.5 KHz. wide) and the frequency remained the same. Channels 001-006 are used in Canada and in the US by some railroad trucking operations.
AAR 107-196
AAR 307-487
Advanced Train Control System
Advanced Train Control System (ATCS) is a combination of wayside signal reporting, on board work reporting and message delievery along the railroad. Most commonly it is found along signaled/CTC rail lines and aids in the approximate location of trains, switch positions, route requests and other railroad specific data. A good source on monitoring ATCS data can be found on the ATCS Monitor website. ATCS data is not available on all railroads or lines. There is no standard channel plan or frequency band for ATCS. Listed are known channels in use, and will vary by railroad and/or location
Positive Train Control
Positive Train Control or PTC is a new GPS and data system to enforce various railroad and federal rules pertaining to train movement. Most railroads will be required to use a form of PTC currently offered by two vendors. This system is designed to be interoperable with other railroads to allow standardizing of data and equipment. Some isolated or passenger railroads may use their own form of PTC such as Amtrak's ACSES on the Northeast Corridor. PTC is independent of other forms of signaling such as ATC/CCS/ATC, but may be overlaid with signal systems. Although there is no dedicated service for PTC by the FCC, railroads have selected the 220MHz spectrum for PTC operations. These frequencies are licensed nationwide.
ITC
This is the Interoperable Train Control (ITC) system used on the North East Corridor (NEC), one of two Positive Train Control (PTC) systems there. Some of the frequencies are the same or overlapping with other PTC systems and steps are taken to minimize interference between the two systems. ITC uses a wider bandwidth (25 KHz.) signal than other systems. ITC is used by freight operators on the NEC and elsewhere.
Amtrak ACSES
Amtrak's Advanced Civil Speed Enforcement System (ACSES) system is used by Amtrak and commuter passenger trains on the North East Corridor (NEC). Freight trains on these tracks use ITC listed elsewhere. Many of these frequencies duplicate or overlap with ITC and other PTC 220 range frequencies so steps are taken to avoid interference.
Train Telemetry
Frequencies listed here are used for train status within the train. EOTD's (End Of Train Device), also known as FRED's (Flashing Rear End Device) are fixed at the rear of most freight trains. This device is linked to the HOTD (Head Of Train Device) also known as a MARY (as opposed to "FRED"). The devices report that the train is moving, air pressure and emergency status of the air valve along with its specific radio ID. This data burst is commonly used by the railfan community that a train is in the listener vicinity. Trains using DP or Distributive Power (remotely controlled locomotives) also use 450MHz frequencies to control such locomotives and transmit information such as power or brake setting, unit ID and other status information. Remote Controlled Locomotives (RCL) are typically found in yards/terminals on yard jobs. Some may be found on mainlines on local jobs but are not used for through trains and are not the same as DP locomotives.