I've looked here and online and can't seem to locate any details in regards to where signals are supposed to be located when used for switches and sidings. I already have the signals. What I'm looking for is a photo or diagram for the general area where these would be placed. I'm not doing prototyping, but want to try and put the signals in generally the right location. Thank you, Terry
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You might want to look at this …..
Just what I was looking for. Thanks Richie! Much appreciated. Terry
@Richie C. posted:You might want to look at this …..
I take exception to some of the diagrams in that file! They are going to lead you astray!
Ok. Do you have any different recommendations for websites, diagrams, etc. that will help me with signal placement? Thank you, Terry
Basic Signal Placement:
That is basic and reliable.
Railroad, time, and location make a big differences. In the Houston area, the SP went from lower quad semaphores, to searchlights to bowling ball looking tri-lights.
Thank you Tom. Nice and easy. Terry
http://www.customsignals.com/track-config-library.php
From Terry at Custom Signals.
More thanks! Great resource. Terry
Semaphore signals on the Santa Fe:
On the Rio Grande:
Again on the Rio Grande:
OK, how did a train know if it needed to go into the siding? Train Order?
At Rocky, the signal post seems to have two sets of searchlights. Because of the curve coming into the switch?
Yes, two sets because of the curve around to the left. You can see the remote switch machine. Even then this was CTC territory (climbing West out of Denver for Moffat Tunnel) so the signal indicated whether you were taking the siding. That is why two signals, one above the other. I don't remember the indications but I'm sure the Railroaders here could fill us in.
@geysergazer posted:Yes, two sets because of the curve around to the left. You can see the remote switch machine. Even then this was CTC territory (climbing West out of Denver for Moffat Tunnel) so the signal indicated whether you were taking the siding. That is why two signals, one above the other. I don't remember the indications but I'm sure the Railroaders here could fill us in.
I believe the signal was like that simply so that the train crew could clearly see around that sharp curve what the signal aspect was. They would both show the same aspect, bu, one could be seen when stopped at the signal and the other seen around the curve.
That was indeed a duplicate signal head, aimed into the curve. It's on the Denver & Rio Grande Western.
The D&RGW did this at only a few locations, in canyons, where a sharp curve preceded the signal and heading-in switch.
Normally, railroad signal departments are very reluctant to even consider signal arrangements like these, referred to as "helper signals" in plain language. Anything this unorthodox carries with it extra safeguarding to ensure that the helper signal accurately mirrors the aspect displayed on the absolute signal facing the standard direction, 100% of the time. The D&RGW use of helper signals was well-known in professional railroading. They did it well, as I can find no evidence of any accidents resulting from problems where there was a helper signal. Nonetheless, signal departments on other railroads wanted nothing to do with helper signals.
There may be a few other helper signals in the U.S., but, if so, I am confident that they were installed over the resistance of the signal department, by orders from a high level of management.
Fellows, this is a great topic, great answers, a learning experience, now, Happy Railroading
Considering tight curves many use on on layouts, that helper signal would be neat.
@Dominic Mazoch posted:OK, how did a train know if it needed to go into the siding? Train Order?
At Rocky, the signal post seems to have two sets of searchlights. Because of the curve coming into the switch?
The signal tells the train if it's going to take the siding, as it's interlocked with the switch machine.
If there are no trains in the area, and no route has been selected, the upper and lower heads of the signal both display red. The switch cannot be moved if the signal is other than at stop.
If the train has to take the siding, the dispatcher moves the switch via remote link. These days it's done with a computer mouse. In former times it was done by a tower operator with a hand lever.
Once the switch is locked for the siding, the dispatcher selects the signal on the computer screen, and clicks. The computer does the rest. Once the signal is set, the train crew will see red on top, green on the bottom. Tower operators set the signal with a foot stirrup right under the switch lever.
The signal goes to red as the train passes it.
If the next train has to stay on the main, the switch is selected for a straight move. All other steps are the same, but this train crew will see green on top, red on the bottom.
The question was for the semaphore signal on the ATSF. Sorry about not being clear.
ROCKY on D&RGW has two signals.
ATSF only has one blade, and I do not think that conveys enough information to tell the engineer to stay on the main or enter siding.
@Dominic Mazoch posted:The question was for the semaphore signal on the ATSF. Sorry about not being clear.
ROCKY on D&RGW has two signals.
ATSF only has one blade, and I do not think that conveys enough information to tell the engineer to stay on the main or enter siding.
Since it was most likely in ABS territory, the siding was manual control, i.e. NOT CTC and thus no power switch machine. If the train was to take the siding, by Train Order instructions, then they would have to stop, align the switch, proceed into the siding, and realign the switch behind them.
@Hot Water posted:
In the ATSF case, I see three semaphores, one facing point and two trailing point. In a case like this, there still has to be a circuit controller that prevents the signal from clearing if the switch is set against it, and the signals from giving conflicting Information.
The signal in this case may show green/vertical blade if the switch is lined for a strait move, and flashing red/horizontal blade for restricted speed if it's lined for the siding. The ATSF operating rules for 1959 do provide a restricted speed aspect that includes semaphores, so this could well be. Itlooks like there might be a building off in the distance where a block operator is stationed, it's too blurry to tell for sure.
This would tie in with the train orders. The crew would be told to take the siding, and the flashing red signal would show them where to do so.
If there's no operator, the signal could also simply be a switch position indicator, and the other two signals be there to prevent the switch from being run through in the opposite direction if it's set against such a move.
Number 90 might have an answer....
I read in Trains that on on the "passenger main" via Raton Pass, there was a horrible headon between passenger trains because someone threw a switch right before the moving one. Atva siding like this one? Again 90 migjt have more info.
Enlarging the picture, I can see the circuit controller. It's the curved bright colored object just above the boardwalk, between the switch stand and the track.
Also, above the relay box base of the signal it looks like there's a smaller box. This could be a push button for the train crew to set the signals after they throw the switch.
That wreck you're talking about, is it the one where the brakeman threw a switch because he claimed the engineer flashed the train's headlight?
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I do remember he threw the switch at the last moment. And it just so happened the engineer on the moving train and the brakeman had bad blood.
On the Rio Grande at GREEN RIVER: Is it unusual to have a yard lead coming onto the main between the signal and the siding switch?
@Dominic Mazoch posted:On the Rio Grande at GREEN RIVER: Is it unusual to have a yard lead coming onto the main between the signal and the siding switch?
I wouldn't say unusual. The operating rules for a particular signal are usually based on the limits of the whole interlocking, not just one switch or crossover. It looks like both the yard lead and the siding switch are powered, and both look like they could be medium speed switches, based on the sharpness of the curve, so the signal in the foreground likely can indicate for either of them.
I was expecting a 3 headed signal. But if it could show flashing aspects.....
For railroads west of the Mississippi, normally the signals were diverging route signals, so yes, if that were the case, there would be three heads. Red over red over green meant the train would take the second diverging route, and the engineer would have to know the speed of the switch.
However, railroads east of the Mississippi usually used speed signals, in which case the signal told the train what speed, and the switches did the rest. Some switches were rated for medium speed, some slow speed. Red over red over green meant slow clear, regardless of whether it was the first switch, second switch, etc.
I know the Rio Grande was a western road, but they may have used speed signals, as we see in the Green River photo.
@Trainman2 posted:In the ATSF case, I see three semaphores, one facing point and two trailing point. In a case like this, there still has to be a circuit controller that prevents the signal from clearing if the switch is set against it, and the signals from giving conflicting Information.
The signal in this case may show green/vertical blade if the switch is lined for a strait move, and flashing red/horizontal blade for restricted speed if it's lined for the siding. The ATSF operating rules for 1959 do provide a restricted speed aspect that includes semaphores, so this could well be. Itlooks like there might be a building off in the distance where a block operator is stationed, it's too blurry to tell for sure.
This would tie in with the train orders. The crew would be told to take the siding, and the flashing red signal would show them where to do so.
If there's no operator, the signal could also simply be a switch position indicator, and the other two signals be there to prevent the switch from being run through in the opposite direction if it's set against such a move.
This is much more uncomplicated.
This is standard Santa Fe Automatic Block System signaling with leave-siding signals. There are hand-operated switches at both ends of the sidings. They are not spring switches in this siding, which is Mindeman, Colorado. Just to the left of the signal and outside of the rail is a signal controller which uses a rod, connected to the switch point, and a crank lever on the controller, to determine when the switch points are not lined for straight track movement, or when the switch is gapped. That ensures that the switch is safe to proceed over at track speed when the signal indicates Proceed. So, in that sense, yes, it is also a switch indicator. Just in front of the signal is a battery well. The Signal Maintainer had to raise the hinged lid and climb down into the underground battery well to check the signal batteries. Often he had to fight some black widows, scorpions, or snakes there.
The heading-in signal which is facing the camera has a phone booth on it. (I know . . . you would expect a building. Some phone booths were little shanties; others were wooden boxes; still others looked like this. All were defined as phone booths.) That was an open communication line (always "on") to the Train Dispatcher. A crew member picked up the receiver and talked to the Dispatcher. There is a motor car set-off next to the switch. Signal Maintainers traveled their territories on motor cars until the 1960's.
This was timetable and train order method of operation with automatic block signals. That is how a train knew that it had to take siding or hold the main track to meet another train. No radio. No CTC. The timetable had the scheduled time of every Regular Train* at every station, and "blind sidings" like this one -- i.e., without a station structure and a train order office -- were still stations in the timetable. Inferior trains headed in:
Train crews had to know where to head in, based on where they would meet or be passed by a superior train. Therefore, Conductors and Engineers had to figure their running time to the next two or three sidings and decide where they would take siding in time to be in the clear of the main track, and have the switches lined back, not less than 5 minutes (10 minutes for First Class Trains) ahead of the scheduled time of the superior train at that station. there were two red block signals and two yellow block signals ahead of and behind each train as it moved over the territory. Meets between Extra Trains were arranged by Train Order, directing the trains to meet at a particular siding and specifying which Extra would take siding. Extra Trains cleared Regular Trains by timetable times of the Regular Trains.
To the left of, and just beyond, the opposing main track signal, you can see an Automatic Train Stop shoe, indicating that this is 90 MPH territory for passenger trains (100 MPH before 1960). There is also one to the right of the camera, but out of view in this photo. They were always slightly in advance of the signal to which they were paired.
The reason all semaphores here are displaying Stop and Proceed or Stop indications is that the photo was obviously taken from the rear of a train that had just passed through the overlapped signals and none had yet had time to return to a Proceed indication.
If a train took siding here, a Trainman would open the siding switch and the blade would drop to display Stop and Proceed. The light would either display a red or flashing red aspect (Santa Fe used both). With the switch lined for the siding, a train could pass the heading-in signal, without stopping (even when the light remained solid red), and proceed at Restricted Speed. This would sometimes happen if the opposing train was already at the meeting point, stopped on the main track between switches. That crew would line the switch for the train which was going to take siding so they could pass the signal and enter the siding without stopping to line the switch themselves.
Okay, I said it was uncomplicated and then I wrote almost a page telling why it was uncomplicated, which seems to contradict my first sentence. Actually, though, it was an uncomplicated method of operation. It relied on the Timetable for meeting and passing Regular Trains, and the rule book told the employees what they had to do. The only time Dispatchers had to direct traffic was when Regular Trains were annulled or substantially late, or when Extra Trains were run. It worked very well. Skill and rules knowledge were required of the employees.
This is impossible today. The legacy skill and knowledge for operating by timetable and Train Order left with the last generation of railroaders who worked under it before the mid-1980's. There are good railroaders out there today, but they operate in an environment in which each train movement on the main track is authorized by signal indication or by Track Warrant or verbal instruction. They will never have their spines begin to tingle when they are trying to get into the clear for the Super Chief and a distant block signal a couple of miles down straight track drops from green to yellow.
* A Regular Train was a train that was authorized by a timetable schedule. (The Employee Timetable, not the pretty public timetable.) The Timetable gave Regular Trains all the authority they needed to occupy the main track, and could be superseded by Train Orders.
I was on Amtrak 3 in May of 1977. So the train was this, or a like line, using the rules listed above. I do remember semaphores going through Raton.
NO 8 RUN 30 MINUTES LATE....
Is that not the EB FAST MAIL? Bad news fot Post Office....
Tom, thanks so much for your short dissertation. You took me right back. I remember the feeling of anticipation approaching a scheduled meet with opposing Varnish on that single-track mainline across high-desert New Mexico on more than one occasion. Here are a couple pics of such meets in which we had taken siding.
Here we are obviously in the hole with the Flagman on the ground protecting us, a formality in this case because he would have closed the switch behind us when we took siding:
In this pic we are back on the Main and the Brakeman has just thrown the switch back to the Main and will step onto our slowly moving train.
Wow, circuit controllers haven't changed. Now you guys have me wanting to model this, and I don't have any Santa Fe equipment.
This would be a great operation for a club layout, especially at a train show. Perfect for command control, docs, legacy, or lionchief.
Of course, it looks like we'd need to add a fourth B-unit.
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