SIGNALS 101: 10 Levels of Train Signal Understanding

In this installment of the Railroad 101 series, we look at Railroad Signal Design! We go over 10 different levels of understanding of signals, focusing on the fun behind-the-scenes stuff that most folks don't get to hear about, as my current job is being a signal design engineer.

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0:00 Intro
1:10 L1: Signal Types; History
5:14 L2: Signal Aspects & Indications
7:42 L3: Local Traffic Control
10:58 L4: Centralized Traffic Control
13:00 Recap 1-4
14:53 L5: Automatic Train Stop
17:02 L6: Track Circuits
24:04 L7: Signal Bungalows
25:22 L8: Vitality, Signal Circuit Design
29:40 L9: Relay Logic Madness
37:03 L9: part 2: Get the green signal
42:20 Recap 5-9
46:02 L10: Microprocessor control
49:08 Outro

[foogeeminipix]

The wavelength of a 60Hz signal is 5, 000 km so either you have very long track circuits in the USA or extremely sensitive phase detectors or, more likely, power frequency track circuits don't work the way you describe.

[walterrogers]

In my 44 years as a conductor, I never realized there was THAT MUCH to consider when designing a signal system. Very informative and educational. Will be watching more of your videos .

[dvone]

I can tell you love your work by how hard you have to restrain yourself from going to Level 20 in your 101 series. Thank you for sharing your passion.

[FerralVideo]

My face lit up when I saw the 12 minutes of relay logic discussion.
I love relay logic!

[DanielinLaTuna]

Very informative! Thanks for sharing.
I was once on a southbound Amtrak in California (in the mid-seventies) when we slowed and came to a stop. A few minutes later the conductor announced that we would be waiting for an unspecified amount of time — Kansas City had lost track of ALL trains and had broadcast an All-Stop signal to the entire traffic. No train could move until the system was restored and the location of each train was determined.
We were grateful for the explanation, and for the protection afforded to us passengers — there would be no collisions that day!

[lwnf]

I work for a signaling vendor. This video is better than our own introductory training materials.

[mikesimmons]

I''m a retired engineer. Very interesting. So that is some of what helped keep my trains and crews safe all those years. New sub.

[leightonmoreland]

I very rarely feel so literally called out....

[vaudevillian]

Brilliant, coming from the UK I always found US signals slightly baffling so this is much appreciated

[DB-thats-me]

Red on the bottom…
Yours is the best explanation, in my 38years railway experience for this situation. 👍

[lordsherifftakari]

understanding Track Signals is also handy for Trainspotters and Train enthusiasts to know what is going on in their area when a Signal is nearby.
speaking of dispatching, when are you going to take another go at the Dispatch simulator?

[joshuadupay]

I am part of a model railway club that runs out of an old 19th century station in northern virginia, and our stations semaphore for train orders still works. We also have a couple of the hoops that they would have used to give train orders to the train crew. Really cool to see that stuff in real life and it helps to really visualize how things worked in the past. We also run operating sessions on time tables and it is so true even on a relatively small scale railroad how easily the time table can get screwed up and the necessity of signals to keep trains from colliding. Really enjoyed the video as always Hyce!

[Armageddon_]

Level 6 reminds me of a situation in Switzerland. Appearantly they use some method (probably with weight sensors rather than electricity) to count how many axles have passed that point (probably use full to indentify runaway cars).
I think you can guess what happened when I say a law was implemented that a train cant have exactly 256 axles.

[robloxthomasrandoms]

Always love the railroads101 videos they are so informational and help a lot for a game I'm making I use these videos a lot to make it accurate to real life thank you!
Keep up the great work!

[MultiMightyQuinn]

This is one of the best explanations I have seen, and this is a topic that really interests me. Thank you for taking the time and putting in the effort to make this video. I really appreciate it, and look forward to seeing more from you. Cheers!

[Two_Bears]

Thank you! So much fun to see this!
I started in the Navy doing motor rewind, then progressed in elevator logic’s and computer controlled motor theory. After I got out, I went into software and hardware design until I was designing processor system at board level. Lastly, I went to networking systems. I learned logics long ago so I fell in love with these relay systems you showed here!
Unfortunately, now I’m old and just want to stare at choo-choo’s and not think anymore. The most complicated thing I do now is trying to understand my navel.

[natecofga]

I have really enjoyed these 101 videos on different subjects on the railroad. I was thinking after your 101 on interlocking and junctions, you should do one on the 101 of switches i.e., turnouts. I know the railroad uses different ones to route trains and locomotives. There are the "normal" switches, 3-way switches, double slip switches, single slip switches, and stub switches just to name a few.

[jacebeleren]

As an electrician, hearing this track circuit information and how frequency changes alter the expected return phase of current flow hit different for me as I'm currently learning advanced AC theory where the relationships of frequency and phase are important for calculating impedance for AC circuits

[russellrattys]

Im in the uk, my grandad told me semaphore signals were set to high for go, low for stop, because if snow built up on the signal and forced it down, that would be a fail-safe, so trains would stop, and telephone a signalman to check whether they could pass the signal or not

My friend went over to America to work on the advanced train protection system, basically if the train ran a red light, power would bw cut from the motor to the traction motors, and the brakes would be applied

[snakeyes]

This video was very enlightening and showed me more about the signals than I really knew. Thank you Mr. Hyce!