Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Uploaded on Apr 27, 2010
In UPRR and NS(Norfolk Southern), the signal located at a simple converging point as shown on this movie may have two-heads and can show diverging signal aspects such as R/G, R/Y and so on. At this time, since the top-head is always R (or may be FR), Y and G light bulbs are removed. In this signaling system, such top-Red type signal can be located by using type-C board. Type-C board translates the single-head signal aspect generated in the type-A board to two-heads or three-heads signal aspects. Hence, type-C board works as a repeater unit of type-A board. These changes of the signal aspect seem to be late. It can be adjusted by shifting the rail gaps.