8 years but im lucky enough to work on both the transcon and topeka sub so i see the oldest signal system and the latest and greatest. Im now a signal foreman and on the road working in tulsa now on the avard sub putting PTC into service.
Thank you. While, yes, you have your hands in a lot of cabinets replacing or even repairing ancient "what were they thinking?", we are talking about a lot of water under the bridge here. Pre-BNSF (1995), pre-Staggers (1982) and pre-FRA (1966) railroading was an entirely different world than what you are living today. PTC? What's that?
Also, given where you are both geographically and within the organization, you don't inherently know what older practice was, say, on the California lines - where there was in fact partial speed signaling between L.A. and San Diego to support the higher passenger train densities. That's not even a BNSF line now, technically, even though you will still find it on system maps.
The Santa Fe I experienced in the '70s was clearly a different organization that what BNSF is today. Chicago (RR HQ) discouraged the local offices from talking to each other, and each division if not each facility operated autonomously, including most purchasing. There was little to no knowledge sharing beyond edicts handed down from on high. There was a lot of "reinventing the wheel" in the divisions, especially in situations where there were conflicts in the practices guidelines from Chicago. "Training" was all local, through the apprenticeship system mostly designed to discourage new talent and protect senior jobs.
Here's an example for you - although I worked for SP at the time in a non-ops department, because of a friend-of-a-friend situation, I spent a lot of time in the Hobart Yard radio shop. I had a railfan and technical interest in railroad 2-way radio, I was doing a lot of heavy research into practices which varied wildly across divisions and RRs, and was writing a book about it. So the shop supervisor, Charlie, relied on me (a non-employee!) pretty heavily for information about frequency use and installation practices outside of what he was "authorized" to know. Heck... I even fixed a few radios when they were swamped. This knowledge was very helpful because this was just before the Syntor (frequency-programmable) era - when a non-company radio showed-up on the bench all they had to do was show me the pack, and I could tell them from the channel elements which railroad it belonged to so they could tag it and send it back to the owner. When the new Barstow yard was under construction, Charlie had to come to me for their frequency allocation plan because he was not allowed to know, at least through company channels, and I had the license information from the FCC database, which was very unusual for the day.
Back at SP, I was preparing timetables, special instructions and rulebooks for printing, including a couple for Santa Fe while the aborted SPSF merger was in process. Prior to that, I apprenticed briefly, yes, with a signal maintainer, although that too often was spent walking the track looking for broken bonds rather than learning exactly what was in the cabinets. Whitney correctly suspected I was a short-timer, so he used me to make his job easier rather than mentor me in the trade.
Anyway, that's a long way of saying there is a lot of firsthand operational and systems knowledge out here in the enthusiast community that can sometimes transcend what you experience on the job today, especially historical knowledge. However, if we have a PTC question, now we know who to go to!
[And don't take this the wrong way, you must be good at what you do... a foreman with only 8 years of experience was absolutely unheard of back then. The old seniority system meant that your foremen had 25, 30 or 35 years under their belts. Experience... or, at least, time holding the job... was above all. Again, a different world.]