semaphore signals

Model Railroader General Discussion (Model Railroader)
1

To all who gave the great advice and honest input to my recent posts, I thanks you so very much. It’s truly appreciated and respected. So…onto my next question. I’m going to continue my station project, but I’m having trouble with the semaphore signals that will eventaully be installed. I found a photo of the type of signal that was commonly used out here, but I need to know the positions the arms were in to indicate ‘go’, caution’, and ‘stop’, and how the colored lenses functioned.

Basically, I’d like some pictures of the arms in each position as I am contemplating a functioning signal, like in the old days. If anyone has pictures or links that would help, I’d appreciated it. I can’t seem to find anything on the Web, as I’m tired of swearing and cussing. lol Help! Thanks for reading.

station

2

Your picture is of a ‘Train Order’ signal. Normally it is green for No Orders to be picked up. Depending on the railroad, it may have yellow/red aspects as well(yellow - train orders to be picked up, or red - train orders to be picked up & signed for). Back in the days of ‘open’ train order offices, the operator could be very busy.

Tomar/NJ Int both have train order signals that are ‘mast mounted’ and IIRC, they have seperate parts as well if you want to build the bracket style in your picture.

Jim

3

SemaphoreSignal - from stuff I’ve read (on the web and one Kalmbach book on signals), there are what’s called “upper quadrant” signals and “lower quadrant” ones. That refers to the ‘Clear’ signal position of the blade (all the way up on upper, all the way down on lower). On both signals, the horizontal position is Stop, and the position at a 45 degree angle is Caution. The lights appear to be to allow the engineers to see (Green, Yellow and Red corresponding to the above 3 in order) the track condition from further away. Sorry for the lack of images, but I’m at work and the links are on my personal 'puter.

Hope that is helpful - have you done a search for “semaphore railroad signals” online? I would expect that the search should turn up some webpages that’d have photos as well. You might also search for semaphore on Wikipedia ( http://en.wikipedia.org ).

Jim in Cape Girardeau

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pb:

If you’ll forgive me a little pedantry, the conditions indicated by the “red”, “green”, and “yellow” aspects, in raiload usage, are “stop”, “clear”, and “approach” (as in, “approach next signal, prepared to stop.”)

“Aspect” and “indication”, to be even more pedantic, have different meanings - the “aspect” is that which the signal displays, the “indication” is what it means. A semaphore actually shows different aspects in daytime (blade) and at night (lights) but they give the same indication.

Model Railroad Engineering, by David Marshall, from 1942, has lots of excellent information on signaling.

The lower-quadrant semaphore is, generally speaking, a two-indication signal, per blade. Straight out is Stop, drooping at an angle is Clear. The blade is weighted to return to the Stop position, and is pulled down to Clear. There were some lower-quadrants that could go vertical for Clear, but they were rare, except possibly as train-order signals.

A lower-quadrant semaphore signal can be arranged to give more than two indications, by putting multiple blades on one mast. Often there were two. The upper was the home signal. The lower, with a fishtail notch in its blade end, was the distant signal, which repeated the aspect of the home signal on the next block. This gave a three-indication signal:

Both blades horizontal - Stop

Top blade drooped, lower blade horizontal - Approach

Both blades drooped - Clear

The one thing I can’t remember is if it was possible to have the lower blade drooped and the upper blade horizontal - it would seem to be pretty meaningless.

Upper-quadrant semaphores can give three indications with one head.

Horizontal - Stop

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Semaphore signals come in a variety of flavors:

  • Train order signals, like the ones in your photo (2 signals on one mast.)

  • Interlocking signals, at places where tracks join or cross.

  • Automatic block signals, where following trains need to know if the track ahead is clear.

There are two basic types:

  1. Upper quadrant - the blade can be horizontal, or raised 45 degrees, or vertical. Horizontal is stop, vertical is clear, half way means pass at restricted speed (or pick up your train order on the fly.)

  2. Lower quadrant - the blade can be horizontal, or dropped 30 degrees, or dropped 60 degrees. Some, which I am modeling, have only two aspects, horizontal or 60 degree drop. (Lower quadrant signals do not drop the blade to a vertical position, since a missing or broken blade is hard to see in that position.) The meanings are the same.

As for train order signals:

  • Clear (arm vertical as in the photo) - no orders for your train.

  • Restrictive (arm at 45 degrees) - orders must be picked up, but train doesn’t need to stop. (If somebody’s arm misses the string the order is tied to, the train DOES have to stop. It can’t proceed unless the order has been received by both the engineer and the conductor.)

  • Stop (arm horizontal) - stop and sign for orders. (If the order places a restriction on that train - emergency slow order, or change to location of a scheduled meet, the conductor and engineer have to sign the agent’s order book to guarantee that they have the clear, ungarbled word.)

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Here’s a pic from my station at Diamond Valley.

The signal has servos and is switched via DCC Loconet from the dispatcher.

Wolfgang

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So, you’re saying that only one arm of the two is positioned, while the other is fixed (in a vertical position)? This is all I really wanted to know, actually, but thanks for the history lesson.

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Just as a clarification, in many rule books the restrictive and stop indications for train order signals won’t say anything about orders. They say a train has to obtain a clearance before passing or departing the station. On roads that keep the train order signal normally set to clear, if the dispatcher wants to copy orders to a station for the Extra 1234 West, as soon as the dispatcher calls the station and notifies them they are to copy orders for a westward train , the operator will set the westward TO signal to stop (DS: “Durand”, Opr: “Durand”, DS:“Copy 5 west.”, Opr: “Signal displayed”…). Assuming there are no other orders to deliver, any trains passing the station between the time the signal is set and the Extra 1234 West arrives will recieve a clearance with the wording “I have no orders for your train”.

The reason some orders have to be signed for (form 31 orders) doesn’t have anything to do with concern over wording being garbled. NO train order should have garbled wording. The reason is that the train signing for the orders is having its authority restricted immediately and the dispatcher must know that the train has recieved the o

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Look at the picture of the Diamond Valley station a couple posts above. Note that the mast has two signals, one for eastward trains and one for westward trains. The train is governed by the signal on its side of the mast, the red signal blade displaying a stop indication. Train is the other direction would be governed by the blade on the other side of the mast, the backside of the blades are painted black and the front sides of the blades are painted red. One mast, two blades one blade/signal for each direction.

So in the picture we can see that the train order signal for the train pictured is set for stop, they have to recieve a clearance and trains in the opposite direction have no orders because the blade is vertical (and since we are viewing it from the back side, its black).

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Both arms work - because one is for trains coming toward the camera and one is for trains coming from behind the camera. Apparently, this prototype left the arms in the clear position unless there were orders to be dealt with. Others (like mine) left the arms in the stop position, not repositioning them until shortly before the arrival time of each train. (The agent would have his employee timetable and all of the orders involving trains passing his station, so would be aware when a train was due.)

Chuck (Modeling Central Japan in September, 1964)