Basic Railfan/Monitoring Conventions

Supremacy of the Road Channel: All activity local to the tracks should be using or monitoring this frequency. Most moving trains will announce location and direction on this freq every couple of miles. The dispatcher will hail the train here. Find out what it is (if you can) before you go trainwatching.

AAR Channel Designators: The Association of American Railroads has channelized the railroad band, and created its own channel designators which are becoming more and more popular as traditional radios give way to synthesized all-channel radios. Each frequency has a two digit designation, and each channel has a four digit designation consisting of the transmit (mobile) frequency followed by the receive (base/repeater) frequency. If you hear someone talk about "Channel 1" or "Channel 2" they're probably referring to a railroad's proprietary channel numbers. If you hear someone mention "1408" or "9696", they're talking AAR channel pairs. Channel 1408 would have the train transmitting on 160.32 and receiving on 160.23, while channel 9696 would indicate that the train both transmits and receives on 161.55. Look for more and more of this in employee timetables.

Employee Timetables: A Railroader's Bible:  These are the tall, thin books designed to fit in an employee's back pocket. They contain lists of stations, interlockings, defect detectors, sidings, radio channels, etc. plus much else of what is needed to operate on a routine basis. Rules and directives for each line, lists of measured mileposts and approved physicians. Usually published at the Division level. Not generally available to the public from the railroads. Look for ads in the railfan magazines, especially those for Carl Loucks.

Navigation by Milepost: All locations along railroad lines are expressed in terms of mileposts. You can often see these along the tracks. You can also find mileage from block signals (divide the number on the plate by 10) and from talking defect detectors. Note that mileposts are not always exactly a mile apart, and there may be some missing. Most railroad mileages were laid out over 100 years ago, and the roads have changed and combined since then. Don't take mileposts too literally, and try to get hold of an employee timetable for the routes that you're interested in.

Identification of Rail Lines:  Most railroads are operationally divided into Divisions. Usually, a division consists of  an entire line or system of lines that work together on a day to day basis. This is further divided into districts or subdivisions, which are the names of particular stretches of track. For example, Norfolk Southern's line from Alexandria, VA to New Orleans, LA is the Piedmont Division. This line is divided into a number of districts, including the Washington District, where the first southbound crew takes its train from Alexandria to Lynchburg, VA. In contrast, NS's Pocahontas Division is not a single line, but rather a group of branch lines that act as tribuaries from the coal mines of West Virginia to staging areas for adjacent divisions.

Track Numbering & Direction: When there are two or more parallel tracks, trains are generally routed along the right-hand track. Since most track direction is reversible, tracks are identified by numbers. There are no set rules. The best way  to determine track numbers is from the railroad's employee timetable or rulebook, or from talking defect detectors in double-track areas. Track numbering usually has to do with track direction, but watch out. Employee timetables declare the direction in which their station lists are ordered, but there are all kinds of considerations that may date back for years. One 'westward' listing actually travels southeast and makes no sense if you don't know the history of that line.

Signals: You should also learn the essentials of reading railroad signals. Specific readings vary from road to road, but general readings are true in most situations you find. Each signal head shows either one colored light (red, yellow, green) or a pattern (horizontal, oblique, vertical). Some railroads like Norfolk & Western combine these two schemes so that green lights form a vertical pattern, yellow lights an oblique, and red lights horizontal. These patterns should also equate in the following explanations.

• Block Signals - These are the signals with only one head (usually) and a number plate (which equals its milepost location multiplied by 10). They are placed along the tracks every two miles or so in order to maintain space between trains. A red signal means that there's a train either moving or stopped in the next block (between the signal you see and the next one down the line), or that traffic is moving towards you from ahead. It doesn't necessarily mean to stop. Yellow means that there's a train in the block past the next signal. Green indicates that the track is clear for at least two blocks and that traffic is moving in the direction that faces the green signal. Note that green is the default setting for block signals, so it can also indicate that no train is nearby.
• Interlocking Signals - These signals normally have two or three heads and are located with track switches. The default setting is all heads red, which means that the train has to stop and wait. Any setting other than this means that the dispatcher has set the switches for an oncoming train to pass. If the top head is green or yellow with other heads red, the train will probably pass straight through the interlocking on its present track. If the top head is red, the train will probably go through one switch. If the top and middle heads are red, the train may be set to go through more than one switch. Note that there are many other possible combinations, but interlocking signal schemes are proprietary with each individual railroad railroad. The bottom line is that any pattern other than all red means that a train is expected.

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