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S Pacific Fan

New Member
Been watching a lot of YT videos on train signals and how to read them. I gotta question that maybe an old timer like me might have an answer to. Back in the late 1950's, say 1959, my family lived about a quarter mile from a set of double mainline tracks in Glendale heading north out of (and south to) Los Angeles. My daddy would walk me with him to the nearest RR crossing to watch the trains, Southern Pacific, going north or south. Back then, at 5 years old, I was allowed to go watch the trains by myself if I wanted to. There was a brick wall to sit on by the crossing gates. About a mile south of the crossing were a pair of searchlight signals, one for each direction. Long story short, I noticed that after a south bound train would knock down the green to red and then the red went dark, that approximately 90 seconds would pass and then the signal would shine a steady yellow light for 1-2 seconds. What was that all about???

Thanks for any input. Have a happy Choo-choo!
I love hearing experiences about the Espee railroad especially here in So. Cal. You lived in one the most interesting times seeing all the different freight cars like Illinois Central, Great Northern, Burlington Northern, Frisco, all the more colorful boxcars...The Espee ruled the day back then. I saw lot of SW1500s back in the 1970's here in Santa Fe Springs Ca. on the Santa Ana Industrial Lead between Alondra Blvd and Carmenita Rd. Back for the yellow light I believe it's to prepare to stop / reduce speed.
Thank you for replying. The yellow light only came on for a coupla seconds then went dark. There was no train coming. After several minutes or an hour or whenever the next train came along, the signal would pop back on to green or yellow or red depending on what was going on down the tracks. Just another one of the mysteries of life.
I had 2 uncles who worked for SP. One was an engineer and I believe the other was a switch man or an engineer. I was born too late to see any steam engines on the line. And imagine my amazement at 4-5 years old when my Old Man would show me a nearby switch and point to part of it and tell me "that is a frog". I thought he had lost it! LOL
That's called approach lighting. The signal is dark until a train passes the next in approach to that one then it lights up. This is to help reduce electricity usage and to prolong bulb life. The yellow wss the signal changing afret the train cleared the block ahead of that signal. Shouldn't have flashed. It's not supposed to light up until there's a train in the block in approach to it.
That sounds to me like a quirk or fluke about how the approach circuit is wired. Can get complicated back then if there are a lot of crossings in front of the signal. is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to - An online railroad bookstore featuring a curated selection of new and used railroad books. Railroad pictorials, railroad history, steam locomotives, passenger trains, modern railroading. Hundreds of titles available, most at discount prices! We also have a video and children's book section. - An online model railroad bookstore featuring a curated selection of new and used books. Layout design, track plans, scenery and structure building, wiring, DCC, Tinplate, Toy Trains, Price Guides and more.

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