... I have my suspicions, but I know you guys and gals will solve my ? I saw several of these trackside in downtown Springfield OH on the NS line. They were flashing intermittent (perhaps three of four in a row, then a slight pause and repeat) "X's". I tried to capture the illuminated X but my camera let me down (that's right, it was the camera's fault). I believe that with so many grade crossings in this area, the city and NS came up with "targeted" audibles (speakers that would sound a train horn but only in the direction of cars as opposed to blasting the entire neighborhood)... So, what say ye? ... an interesting trackside to model.
Around here they are used in conjunction with trackside horns in "quiet" zones. The horns are on the mast and pointed at approaching traffic only. The locomotive only blows his horn when the "X" is not illuminated indicating a problem with the safety crossing equipment. The horns focus the sound at the traffic and don't broadcast it all over the neighborhood. Thus fewer decibels are required making the area is much quieter so the natives are not as restless.
