AAR FREQUENCY LIST

The American Association of Railroads have identified a list of 96 standardized radio frequencies that are used by North American Railroads.  The AAR has assigned a channel number to each of the 96 frequencies that occur in this block that is used primarily in the United States and Canada.  Most railroads identify the AAR frequency channel assignments in their radios and use that designation for timetables and communications regarding use.  The railroad radios employ a duplex system that can transmit on one frequency and receive on another.  For example, if CSXT references a subdivision or line that is using AAR Channel 5050, the frequency that both the dispatcher and train crew would be transmitting on is 160.860 MHz.  If however, the subdivision or line uses AAR Channel 1494, the frequency being transmitted on by the train crew would be 160.320 MHz and the dispatcher would be using 161.520 MHz, though on the railroad radio there would be only one radio capable of transmitting and receiving on the separate frequencies.

End-of-Train (EOT) devices (or FRED) are actually a series of communications between the locomotive and the EOT that transmit at two separate Watts and are typically limited from 3 to 5 miles.  The locomotive sends its signal, a distinctive chirp, on 452.9375 MHz, while the EOT transmits on 457.9375 MHZ.  Use of these non-AAR frequencies may aid in tracking down a train, as even if there is no verbal radio communication, if the train has an active (working) EOT, there will be an audible chirp.

One exception to the EOT device is that Norfolk Southern has used devices that employ their signature chirp on AAR 67, 161.115 MHz.  It works similarly to the above EOT explanation, just with a lower MHz frequency rating.

The following table converts from AAR channel number to the appropriate radio frequency (MHz).

Ch Frequency Ch Frequency Ch Frequency Ch Frequency
02 159.810 26 160.500 50 160.860 74 161.220
03 159.930 27 160.515 51 160.875 75 161.235
04 160.050 28 160.530 52 160.890 76 161.250
05 160.185 29 160.545 53 160.905 77 161.265
06 160.200 30 160.560 54 160.920 78 161.280
07 160.215 31 160.575 55 160.935 79 161.295
08 160.230 32 160.590 56 160.950 80 161.310
09 160.245 33 160.605 57 160.965 81 161.325
10 160.260 34 160.620 58 160.980 82 161.340
11 160.275 35 160.635 59 160.995 83 161.355
12 160.290 36 160.650 60 161.010 84 161.370
13 160.305 37 160.665 61 161.025 85 161.385
14 160.320 38 160.680 62 161.040 86 161.400
15 160.335 39 160.695 63 161.055 87 161.415
16 160.350 40 160.710 64 161.070 88 161.430
17 160.365 41 160.725 65 161.085 89 161.445
18 160.380 42 160.740 66 161.100 90 161.460
19 160.395 43 160.755 67 161.115 91 161.475
20 160.410 44 160.770 68 161.130 92 161.490
21 160.425 45 160.785 69 161.145 93 161.505
22 160.440 46 160.800 70 161.160 94 161.520
23 160.455 47 160.815 71 161.175 95 161.535
24 160.470 48 160.830 72 161.190 96 161.550
25 160.485 49 160.845 73 161.205 97 161.565

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