Correct Answer - Option 1 : outer signal only
Explanation:
Classification of signal based on location characteristics:
(1) Reception signal:
(i) Signals which control the reception of trains into a station. These signal are related to the station section (station section is that section which comes under the direct control of that station and it is this particular section in which trains remain stationed at that platform).
(ii) Here, also we have two types of signals:
Outer signal:
(i) Outer signal is the first stop signal before the train enters from the block section to the station section.
Home signal:
(i) Home signal is just provided at the door of the station (signal just before reaching the platform).
(2) Departure signal:
(i) When the train standing on the platform and it has to depart, at that location the signal provided to dispatch the train from the station are known as departure signal.
(ii) Departure signals can be subdivided into two types:
- Starter signal
- Advance signal
(3) Routing signals:
(i) It is a group of semaphore signals placed at facing point of a cone or a number of turnouts.
(4) Shunting signal:
(i) Used for shunting operations (It is the slow operations which take place in station yard) in station yards.