I would like to install these on my layout. What is the standard for locations of these post? What is the distance from the intersection of road and track that these post are located? Any info would be greatly appreciated! John
Usually a quarter mile before the crossing unless it's a slow speed railroad. If you are traveling track speed and start whistling for the crossing when you pass the post, you should finish the whistle signal as the engine hits the crossing. The last note of the crossing signal should be before the engine reaches the grade crossing.
I can't speak for the rules in effect before it became BNSF, but here's how things are today. Whistle boards are located 1/4 mile from the crossing. At speeds 45 mph and greater, sound the proper whistle sequence at the whistle board. Continue sounding the sequence until the crossing is occupied. At speeds below 45 mph, delay sounding the proper whistle sequence at least 15 seconds before, but no more than, 20 seconds before occupying the crossing. The interpretation used by my bosses, Road Foremen, Managers of Field Training, regarding repetition of the whistle sequence is that you sound the proper sequence, long, long, short, long, and repeat until you completely occupy the crossing. You can end on a long or a short, it doesn't have to be a complete sequence. For multiple crossings spaced closely you don't have to sound a single sequence for each crossing. Depending on how closely the crossings are spaced, your "longs" could be interpreted as "shorts" if you try to fit one sequence in for each crossing. Usually what I do for two spaced closely together is finish the first sequence before reaching the first crossing, then start another sequence that ends as I occupy the second crossing. That way the sequences are uniform and provide the desired warning effect. After all, that' s why we're sounding the whistle! When I go to Oklahoma City on the BNSF Fort Worth Subdivision, there's a ton of crossings each a block apart just north of the passenger depot before you get to Nowers. I blow a normal sequence that covers two or two and a half crossings, depending on speed, and just repeat until I'm through town.
1/4 mile in advance. The quarter mile is a federal standard based off the loudness that a horn is supposed to be. Most signs are placed 10 feet from the nearest rail. All the bells, lights, whistles, sizes of signs and so forth have standards. Like the gates are supposed to close 30 seconds prior to the train occupying the crossings. In case of a accident, they measure all that stuff. In the bungalow all that is recorded. Plus all the signals are recorded, when they change.
Dale at Blairline Models makes some dandy Frisco-specific signs. http://www.blairline.com/hisigns/ First image is a full sized example from the Clinton Subdivision after it was retired. From the 1975 Standard Plan. Note the location details. From the 1914 Standard Plan.