Using Semaphore Signals rather than Colour Lights

So far, this tutorial has used colour light signals. However, semaphore signals can be used in place of colour lights.

Bear in mind that this approach to signal control is based on signalling techniques which are not the same as a lever frame in a signal box. There is a presumption that the signals will go to "proceed" if the line is clear ahead, rather than the signalman in his box only pulling the levers for the signals when he is ready for a train to proceed.

There is also a feature yet to be developed; at present the instructions to change state are sent to all signal heads simultaneously. Thus, if you have a mast with two semaphore arms (say a home plus distant), it is likely that both arms will move together. A feature enhancement request to change this within JMRI has been made, but no date yet given for implementation.

Creating semaphore masts

A Semaphore Mast is created in the same way as a colour light mast. The arms are each defined as "signal heads" and the combination of arms (heads) are made onto a Mast. The definition of the Mast is in the signalling rules of the prototype, in our demonstration layout this is BR signalling.

Once the Mast has been created, it is positioned at a block boundary in the same way as the colour light signals, and the rules from one signal to the next created in the same manner as before.

The Video covering this part of the tutorial is in preparation.

The download of the panel file with the bay signal replaced with a semaphore can be downloaded below:

[ Link to download panel file ]

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