Entry Signal Aspects and Indications
Exit Signal Aspects and Indications
Block Signal Aspects and Indications
Rear View of Main Signals
Multiple Entry Signals
Stop.
Stop, then proceed to the end of the Entry Route. Maximum speed 30-40 km/h (20-25 mph). Entry Route may be occupied. Next signal must be expected to show "Stop". Aspects in use 1953-1990(?).
Proceed on Entry Route at prescribed speed. Stop at the station. On stations with Main Signals at the exit end, through trains may omit stopping if signals allow them to proceed. Aspects in use from 1903.
Proceed on Entry Route at prescribed speed in accordance with route direction indicator. Stop at the station. Aspects in use 1935-1953.
Proceed on Entry Route at prescribed speed in accordance with speed indicator. Stop at the station. On stations with Main Signals at the exit end, through trains may omit stopping if signals allow them to proceed. Aspects in use 1953-1990(?).
Proceed through station at prescribed speed. Exit Signal (if any) shows "Proceed" or better. Aspect in use from 1903.
Proceed through station (junction) at prescribed speed in accordance with route direction indicator. Exit Signal (if any) shows "Proceed" or better. Aspects in use 1935-1953.
Proceed through station at prescribed speed in accordance with speed indicator. Exit Signal (if any) shows "Proceed" or better. Aspects in use 1953-1990(?).
Exit signals are used in different ways:
Either 1 Exit Signal per track, controlling departure and line access;
Or 1 Exit Signal per line controlling line access only. Departure from individual tracks
is controlled by Route Signals, Exit Block Signals etc.
For the first purpose, older exit signals might have 2 or more arms, the top arm indicating the leftmost track and so forth. See also Route Signals.
Information in this section also applies to Exit Block Signals, however, these were always equipped with 1 arm only.
Stop.
Proceed at prescribed speed. Expect next Main Signal to show "Stop" or to be advance signalled by a distant signal. Aspect in use 1935-1986.
Proceed from the relevant track at prescribed speed. Expect next Main Signal to show "Stop" or to be advance signalled by a distant signal. Aspect in use 1935-1973.
Proceed at prescribed speed. Route is set according to route destination indicator. Expect next Main Signal to show "Stop" or to be advance signalled by a distant signal. Aspect in use 1953-1986.
On certain lines, older block signals were equipped with arms for both directions of travel.
Stop.
Proceed at prescribed speed. Expect next Main Signal to show "Stop" or to be advance signalled by a distant signal. Aspect in use 1903-1972.
To enable monitoring of signal aspects, entry signals are equipped with colour filters for rear view. Yellow and white lights are used for this purpose, the white light being filtered by a "pinhole". The example below illustrates the scheme used since around 1935. Exit Block Signals used to have a similar feature.
Before the introduction of route direction indicators, a junction might have 2 (or more) entry signals per track, each signal corresponding to a specific route destination through the junction. The signals could be situated on a gantry as illustrated below, or on separate posts next to the track. From 1953 most of these multiple entry signals were replaced by colour-light signals with "Diverging" aspects (refer to entry signal description). However, one pair remained in use until 1979.
As these signals were usually found at junctions without exit signals, the "Proceed" aspect was rarely used.
Stop.
Proceed through junction at prescribed speed in accordance with route indicated. Exit Signal (if any) shows "Proceed" or better.