Do any of your museums display or demonstrate cab signal systems, and if so, would you share a description of how you display and/or demonstrate them? Do you have the equipment on a wall display, in a display case, or do you just use photos and printed materials for explanation? Do you have any aspect displays wired so that individual aspects can be selected and lighted by visitors? Do you make any effort to differentiate and explain various aspect display unit arrangements such as color light, position light, and integrated speed dial aspect displays? And have any of you gotten to the point yet of trying to "interpret" the Amtrak ACSES system for your visitors?

Thanks,

PC

I recall the Museum of Science and Industry in Chicago had a steam cab mockup, but I don't think it had cab signals. They had the big Santa Fe O scale layout which is now replaced with an HO layout depicting transcontinental railroads. I havent visited it yet so no idea if they have cab signal demonstrations there.

Last year at the Trainfest in Owosso Michigan one or 2 locations was running the Microsoft Train Simulator and a few cab scenes have cab signals. No one was really educating about cab signals tho.

Not a cab signal but I think the NYC museum in Elkhart has an active track indicators for the rail line just outside the station it is in.

Its always been my dream if the Clifton Forge museum concept gets going to have some interactive railroad feature, that would obviously include cab signals.

I've visited a few other museums but don't recall cab signals there.

I think the North Judson has a complete Signal tower with all its levers they are restoring, its not cab signals but an impressive display about signal control anyways!

cheers.

The 3 cylinder Baldwin steam loco in the Franklin Institute in Philadelphia has Pennsylvania Railroad cab signals. At one time, there was a 4 push button box, 1 for lighting up each indication. I don't know if it had automatic train stop.

I seem to recall that the Railroad Museum of Pa. has, somewhere amongst their many exhibits (including a functional PRR position-light signal) a display showing the concept of cab signals and how they worked.

Of course, with such stuff as Positive Train Control coming down the pipeline, we'll have a far more complicated system to explain in the future.

I think it would be great for a museum to have a quality cab signal display. Before the roof collapse, the B&O museum had a decent reduced size display on CPL signals, as well as a mock-up of a standard AAR control stand. I thought that was fairly well done, but looks to be lost now.

I tried several different locomotive simulator displays at museums from the East to the Central U. S. and found none of them to be all that satisfying. Probably the one that came closest to real for me was one at the Swiss National Museum of Transport in Lucerne.

If anyone is interested, I'd be willing to put on a program explaining cab signals and signal rules - at least for NORAC and CSX. If you want GCOR or any other rules, you'd have to find someone more familiar with those rules. I know from having had run-through UP power that their cab signal system differs in some important ways from CSX and ex-CR territory that I didn't understand.

Paul, I would encourage you to let the groups in your area know of your willingness to talk on those topics, you might find some very interested audiences. One of the most fascinating talks done in my area recently was a railroad communications discussion by a technical specialist who brought in some of the equipment to view and demonstrate.

I have been wondering just how small and limited a system could be built around a modern nine aspect ADU with integrated color light and speed dial to allow it some functionality, perhaps to demonstrate a departure test at a museum, running all the aspects on the dial. This might require a button to allow acknowledgement of the penalty in place of suppression, since you would not want to provide a complete 26 LU-L just for this purpose. I may try to verify all the circuits between the cardfile and the ADU to see if any limited display functionality could be provided for the ADU without needing the entire rack of equipment. What would be nice for display purposes is if a mockup stand with a model locomotive on a treadmill could operate with the ADU, and you could set an aspect then bring the locomotive up to speed and hit the penalty. It would not need to work the same way the system does on a locomotive with the full cardfile and the mother board, it would just need to be able to light the aspects, display the speed, and initiate the penalty. Maybe even a gutted ADU specifically lighted and wired for this purpose with a relay logic type circuit substituted for the sophisticated electronics could do the job.

I have been curious whether anyone else has already tried anything along these lines.

PC

Preston;

You just exceeded my knowledge of this stuff by a factor of ten. I understand how it works on a practical level, not a technical one. I just ran the departure test and used the system by the rule book (and called the Help Desk when it didn't work, and the Chief Dispatcher for permission to run without cab signals if the Help people couldn't do me any good). However, maybe it's possible to get some version of Train Sim. to run some type of cab signal demonstration, either running through the departure test, or preferably showing how the various functions work going down the road - overspeed, downgrade of aspect, etc. - and what the engineer has to do to respond to each change.

Considering most fans don't even know what signal aspects mean apart from maybe Clear, Approach, and Stop, and the general public doesn't even understand that, some kind of demonstration that explains the basics clearly would probably be well-received. Combine that with a short explanation of the signal rules for the audience's dominant local railroad, and you've got a pretty good program that could be put into a Power Point format.

One of my favorite discussions that I have when traveling with non railfan friends and we come across a railroad signal is to explain how railroad signals work and what the indications mean. To the average person a signal is a device that controls permission to pass a single point: a traffic light covers THAT intersection; railroad crossing lights covers that set of tracks and so on. But on the railroad, a signal controls not only the simple stop and go permissions, but also can tell you what speed to run at, how to proceed and the status of track miles ahead. So before you can explain the meaning of a signal indication you first have to discuss the physics of railroading, how trains are routed and governed on the main line.

When I first hired out on CSX all of us "professional hires" went to a three week basic training school in Atlanta, GA. Some of the students had only worked on short lines and never experienced signals, and even our instructors were veterans of service on an unsignaled branch line and never got out on the main. So they had difficulty in trying to explain signals to students, kind of like the blind leading the blind. Some of the students were naturally worried since failing the school meant getting fired from CSX. I had a good understanding of signals since as a railfan that was one of the things that I studied. So I did a bit of tutoring during breaks for the ones having trouble. I would draw a simple track diagram with sidings, break it up into blocks with signals, and then describe some hypothetical scenarios of indications that trains would receive depending on what was ahead of them. I was blown away when later on a couple of my fellow students said that just drawing out the diagram and explaining the signals allowed them to finally figure out how the whole system worked, and probably meant the difference between passing or failing the school.

Thanks for your postings. I Hope I did not make my post too technical, what I was "thinking in print" is whether it is feasible (or possible) to jury rig the Aspect Display Unit (ADU) to light the aspects and provide a speed readout without the very expensive electronics in the main circuit box. It will vary with the manufacturer and system, but might be possible to do. I don't recall seeing manufacturers internal circuitry for the systems, but I may be able to figure that out from my locomotive schematics by tracing through the inputs and outputs from the ADU. It would be nice if there is a relatively inexpensive way to illuminate the aspects and speed readout for museum display.

The ADU is a marginally expensive component new, but they are occasionally available as salvage. The circuit box is very expensive, and they are almost never seen on the salvage market. If an ADU could be jury rigged into a workable display item, it might be worthwhile information for a few museums.

Paul's PowerPoint idea has great merit, and actually a self running PowerPoint program with photographs and artwork is another alternative to displaying actual equipment.

PC

I was able to "somewhat" answer my question, at least for a recent nine aspect cab signal system by a prominent manufacturer. The ATC/ACSES calls out signal aspects to the event recorder on individual circuits each indicating a particular aspect (basically on/off inputs), but it does NOT call aspects out to the ADU with those same circuits. It looks like the ADU is reading code, which makes it a whole lot more difficult and complicated to jury rig it as a display.

PC

Sounds like a job for a modern microcontroller. This would be a good thing to be fluent in:
http://arduino.cc/en/Guide/Introduction

Preston;

Part of this already exists if it's possible to adapt the program. One of the routes available for use on Microsoft Train Simulator is the RF&P Sub from Fredericksburg, VA to DC for VRE commuter trains. I'm not a gamer, so I have no idea what it actually looks like, but the route is cab signaled, and if you could modify the video display (if it doesn't already) to show the light tree and what is displayed on the CRT screen of a modern locomotive, you could run through most of the functions of that cab signal system and screen capture it for use in a PP presentation. It would be a really good one to use, since the system also includes a Locomotive Speed Limiting (LSL) function, which many systems don't include.

Paul, thanks for the interesting idea.

PC

Are there any good resources easily obtainable by those of us who would like to learn cab signaling and train control in general? I did some internet searching, and there seems to be some stuff out there on how the PRR ran their operations, but not much on modern signaling.

In the "old days" US&S and GRS produced some excellent instruction pamphlets that described the hardware and the functioning of their systems. US&S bulletin 105 covering continuous train control is an excellent example of this kind of reference. Nowadays these are getting hard to find and are actively fought over when they appear on internet auctions.

Finding readily available information on current systems like PHW five aspect and the PHW nine aspect integrated with ACSES is much more difficult. There is very good reference material available that shows the hardware and explains the systems, but it is in the maintenance manuals of relatively new motive power and seldom appears outside the railroad operating the equipment. For example, a recent MP36 maintenance manual has chapter 15 (cab signal) and chapter 16 (ACSES), both quite comprehensive with illustrations of all the devices, detailed explanations of how they function, and a full table of code menus for all the aspects the system displays. But that information is not generally available outside the agency that owns the locomotive.

Railfan market books on railroad signaling have tended to overlook cab signals and ACSES, probably because photography of the equipment is less interesting and more difficult than lineside signals. Color light and position light signals with a train against a sunset make much nicer images for publication than a CAB80 viewed over an engineer's shoulder as you race past graffiti covered factories. Some coffee table books on railroad signaling unfortunately have technical errors, something often overlooked by book reviewers who may not understand the systems well enough to be able to recognize them.

And of course the final problem - there are relatively few people in the railroad industry who deal with the technical support of cab signal systems and even fewer who are motivated to write about them.

PC