theseaandalifesaver wrote:Why were they never upgraded to be the same throughout the entire line? Having different signals on the NEC sounds like it can be a nightmare. Are most of the physical signals the same from the pre-amtrak days?
They weren't upgraded to be the same as that costs money and many are the same physical signals from before Amtrak acquired the Corridor. And they aren't all that different (B&O style signals excepted), particularly now that most position light signals have had color added. A head on a position signal is the equivalent of a single light on a color (only) signal. So the vertical two greens on a color position signal or the three vertical lunar on an uncolorized position signal is the same as a green on a color signal. Even before they were colored, there was an easy correspondence - vertical lights were the same as green, diagonal (high on the right) the same as yellow, and horizontal the same as red. Diagonal (low on the right) means Restricting and is equivalent to lunar or a bottom yellow with everything above it red. While after a short time, any railroader learns signals well enough so that you look at the aspect and your brain immediately knows what signal and indication it is (as I was once taught, Aspect = Appearance and Indication = Instruction, an easy to remember mnemonic so you can remember what Aspect and Indication mean), a railroader who can translate positions to colors can read almost any position signal (e.g. seeing three horizontal lunar over three vertical lunar translates that to red over green which is Medium Clear) (the only signal I can find that fails that translation is horizontal over diagonal (up on right) which is Slow Approach but if you think of it as Red over Yellow, that's Restricting which is more restrictive so the translation fails "safe").
One last thing: the positions of position signals match the position of blades on semaphore signals. Despite the appearance differences, there is more in common than different.