Back to Railroad Monitoring

Table of Contents


General Traffic
UP Radio Network
Frequencies
Map of UP Radio Network
General Traffic

When calling a dispatcher, most radios have a dispatcher button on them. By pushing the button, the radio transmits a tone over the road channel (audible to a scanner and ear) and that in turn alerts the dispatcher in Omaha. When the dispatcher is ready, he will announce he is ready ("UP Omaha Dispatcher ## Over"). If the radio does not have a dispatcher button, the operater must have a specially calibrated Tuning Fork. Then, the operator should strike the fork against something solid, and transmit the tone over the radio by placing the fork next to the mic for 3 seconds. DTMF tones are used for the PBX system. By pressing * and two digits appropriate to that PBX system, the PBX system will activate and give dialtone. Once the call is completed the # followed by both digits deactivates the dialtone.
The UP Radio Network


160Mhz - General Traffic/Operations

All traffic that a scannist wants to hear will be in the 160Mhz range. Here you will find the only audible link between the dispatchers and the trains/engineers themselves. You will also hear train to train and maintanence cars on the "road" channels. PBX lines allow a person to obtain a dialtone over the air and place phone calls. Other miscellaneous tactical and operations traffic will be heard in the 160Mhz range also. These frequencies are then monitored and picked up by microwave relay stations scattered throughout. (more below).

450Mhz - Telemetry/Control Data

The end of trains have a little black box on the car joint that is attached to the airline and other pertinant train "stuff". This box has a small UHF antenna to transmit the end of train data to the engine, and a blinking red light for safety purposes. These end of train monitors can be found on 457.9375Mhz. The engine also transmits information in digital data format on 452.9375. This freq might be heard better due to power and antenna location on the engine. This will tell you when a train is nearby as you pick up these low power transmitters. Just a bunch of noise - nothing of non-railfan interest. On longer trains that need extra engines either in the back or middle of the train (called Power Units, Pushers, Helpers, Distributed Power), the 450Mhz frequencies are also used to control those helper units from the front of the train - using telemetry to control brakes and power needed. Again there is nothing really worth listening to except for the occasional data burst at low power - something train buffs can use to chase a train.

890/950Mhz - Train Control, Digital Computer Network
Signals and switch controls are often controlled by the dispatchers in Omaha or if on a Direct Traffic Control situation like Roseville Yard via radio. You can see some examples at sidings along the mainline of Union Pacific. Brock siding - north of Lincoln, CA has a 890Mhz yagi pad at one end of the siding. I believe Rawson siding has a 7 element yagi antenna at the north end of it as well.
The 950Mhz frequencies licensed to the AAR are used for the North American Joint Positive Train Control Program. This system is used currently for the digital links between cab computers and dispatchers. They can do train orders and requests via computer between the dispatcher and engineer. The future goal being implemented across the network is for a Positive Train Control system. This will allow the dispatcher to stop, start, manage, control, observe and monitor and engine/train within his/her domain. A person in Omaha will be able to slow a train down in Northern California this way.

Microwave 6600Mhz - the Backbone

This network of microwave links and fiberoptics by far is one of the most outstanding radio networks in existance in the western US. Just how does an engineer talk into his radio in Northern California and have his voice come through the headset of the dispatcher in Omaha, Nebraska? Likewise - the dispatcher talk back to him, knowing and selecting the appropriate repeater to talk back on? All this is part of the elaborate "backbone" that supports and keeps the major UP railroad flowing smoothly along its tracks. When a radio is keyed up on the Road Channel with the intention of talking to the dispatcher, receivers placed on mountaintops (see map below) pick them up and convert them to microwave signals at 6600Mhz. These microwaves are then bounced between repeaters north or south to Roseville, California. From there, the major switchroom then receives and converts the microwave to light pulses that will travel across 3 states via fiber optics to Omaha, Nebraska. On return, the dispatcher in Omaha talks back, going through the fiber, to Roseville and over the microwave system, to the selected transmitter that converts it to 160Mhz and thus into the engineer's radio.

This same system, being the "backbone" as it is, carries over 600 voice channels across it. Everything from the road channels to the PBX channels, the signal controls to the inner-office phones of the Union Pacific all travel across the microwave link. This system is currently analog and being phased out to cover digital traffic and thus increase the number of channels available. Going digital will also help implement the future Positive Train Control, allowing easier, cleaner digital transmissions rather than analog signals. Remember though, this digital/analog switch will not affect us as scanner listeners. The traffic we hear on 160Mhz will not go changed, only the "behind the scenes" of radio waves will switch to digital.
Ch
Freq
 Ch
Freq
 Ch
Freq
7 160.215 38 160.680 69 161.145
8 160.230 39 160.695 70 161.160
9 160.245 40 160.710 71 161.175
10 160.260 41 160.725 72 161.190
11 160.275 42 160.740 73 161.205
12 160.290 43 160.755 74 161.220
13 160.305 44 160.770 75 161.235
14 160.320 45 160.785 76 161.250
15 160.335 46 160.800 77 161.265
16 160.350 47 160.815 78 161.280
17 160.365 48 160.830 79 161.295
18 160.380 49 160.845 80 161.310
19 160.395 50 160.860 81 161.325
20 160.410 51 160.875 82 161.340
21 160.425 52 160.890 83 161.355
22 160.440 53 160.905 84 161.370
23 160.455 54 160.920 85 161.385
24 160.470 55 160.935 86 161.400
25 160.485 56 160.950 87 161.415
26 160.500 57 160.965 88 161.430
27 160.515 58 160.980 89 161.445
28 160.530 59 160.995 90 161.460
29 160.545 60 161.010 91 161.475
30 160.560 61 161.025 92 161.490
31 160.575 62 161.040 93 161.505
32 160.590 63 161.055 94 161.520
33 160.605 64 161.070 95 161.535
34 160.620 65 161.085 96 161.550
35 160.635 66 161.100 97 161.565
36 160.65 67 161.115    
37 160.665 68 161.130  
To the left are the AAR/FAP channels 7 through 97. Anywhere you see a four digit number like 6060 or 4753 these are channel pairs that are used. The first is TX and the second is RX and most of the time they are the same. 4753 would be for instance 160.815 and 160.905. The railroad radios are all two channel radios with the display showing the 4 digits. On Amtrak you will see the conductors with these radios.

Below you will find UP and other railroad frequency lists.

Union Pacific

Road Channel 160.230
Road Channel 160.320
Road Channel 160.470
Road Channel 160.515
Road Channel 160.800
Road Channel 160.875
Road Channel 161.310
Road Channel 160.550
PBX 160.290 (TX on 161.520)
PBX 160.605 (TX on 161.025)
PBX 160.890 (TX on 161.040)
PBX 160.950 (TX on 161.160)
MofW Car to Car 160.605
MofW Ops 161.400
UP Police Mutual Aid 161.205

Roseville Yard Ops
Trim Switching 160.275
Trim Switching 160.395
Hump Swithcing 161.100
Hump Switching 160.980
Switching 161.430
Purchases and Materials 161.490
Yard Master 161.400
Car Department 160.350 (TX on 161.130)


Other raillines

Northern California Crane 160.380
Almanor Railroad system 158.310
Amtrak On Board Services 160.445 (160.440 between Bakersfield and Oakland)
California Northern Road 161.385
California Northern Switching 160.635
McCloud Road 160.695 (TX on 161.325)
McCloud Switching 160.860
McCloud Switching 161.025

Tourist/Excursion Trains

CA State Railroad Museum Admin 160.335
CA State Railroad Museum Sac Southern 160.335
Golden Gate Railroad Museum 160.635 (trips on 2472)
Napa Valley Wine Train 160.575 (TX on 161.475)
Portola Railroad Museum 161.010
Roaring Camp and Big Trees 151.925 Ops
Santa Cruz, Big Trees & Pacific 160.995
Santa Cruz, Big Trees & Pacific 160.320 joint UP ops