London Bridge signals question
 

In article .com,
writes
And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?

This kind of indicator was originally used in music halls or theatres to
indicate which act was being shown; the railway then appropriated them.
So both "music hall type" and "theatre" are reasonable names, though the
former probably went out of use as the music halls did.

Technically they are "alphanumeric indicators meeting sighting
requirement class 2", if I recall correctly. Stencil indicators meet
sighting requirement class 3.

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Fax: +44 870 051 9937 | Work:
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London Bridge signals question
 

On Sat, 31 Mar 2007 22:59:14 +0100, G
wrote:

I've seen RA indicators at Manchester Victoria, where there are no
single manned trains. Are they serving the same purpose?

Yes. For whatever reason (perhaps repeated "ding-ding-and-away" SPADs
or something), it's been decided that the traditional approach of the
guard giving the RA isn't appropriate at that station, so instead the
guard closes the doors then shows a green flag to the platform staff,
who then activate the RA and the train departs.

I think Manc Picc has it as well.

Neil

--
Neil Williams
Put my first name before the at to reply.

London Bridge signals question
 

"Clive D. W. Feather" wrote in message
...
In article .com,
writes
And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?

This kind of indicator was originally used in music halls or theatres to
indicate which act was being shown; the railway then appropriated them. So
both "music hall type" and "theatre" are reasonable names, though the
former probably went out of use as the music halls did.

That's interesting. I'd always assumed that the name came from the fact that
the usual shape of the display (rectangular, and shaded) looked vaguely like
a stage as it appears in theatre when the house lights are down - I always
wanted the ones at Waterloo to have curtains which would dramatically part
to reveal... "ta-da...MT" or whatever.

Another illusion shattered.

Technically they are "alphanumeric indicators meeting sighting requirement
class 2", if I recall correctly. Stencil indicators meet sighting
requirement class 3.

Linking in with the other current thread on signal visibility, I presume
that class 1 is "8 seconds at line speed on the road", class 2 is less
strict than that (but still used in cases where they need to be visible from
a moving train), and class 3 is only for cases where the view will be from a
train standing at a platform waiting for the RA. Is that right?

Regards

Jonathan

London Bridge signals question
 

On 1 Apr, 13:11, "Jonathan Morton"

That's interesting. I'd always assumed that the name came from the fact that
the usual shape of the display (rectangular, and shaded) looked vaguely like
a stage as it appears in theatre when the house lights are down - I always
wanted the ones at Waterloo to have curtains which would dramatically part
to reveal... "ta-da...MT" or whatever.


I thought it was something to do with the etymology of 'theatre',
which is from the Greek "to behold". We live and learn...

On the subject of theatre type indicators, was there anywhere else,
other than Liverpool Street, that used them with non-alphanumeric
indications? At the ends of the Liverpool Street platforms they used
to display a horizontal line of lights, each light representing a
route from left to right, with a light above and below the route set.
So you had a single horizontal line of lights, except for the set
route which had a vertical line of three.

London Bridge signals question
 

In article , Jonathan Morton
writes
Linking in with the other current thread on signal visibility, I presume
that class 1 is "8 seconds at line speed on the road", class 2 is less
strict than that (but still used in cases where they need to be visible from
a moving train), and class 3 is only for cases where the view will be from a
train standing at a platform waiting for the RA. Is that right?

GK/RT0031 says:

B27.5.1 Performance category 1 equipment
All equipment meeting the requirements of performance category 1 shall
be designed to be readable at speeds up to 125 mph.

B27.5.2 Performance category 2 equipment
With the exception of the banner repeating signal, equipment which meets
the requirements of performance category 2 shall be designed to be used
only where the approach speed of trains requiring to read the indication
does not exceed 60 mph.

B27.5.3 Performance category 3 equipment
With the exception of independent position light signals which are
pre-set by a main route, equipment which does not exceed the
requirements of performance category 3 shall be designed to be used only
where there is no requirement for the aspect / indication to be read at
a speed exceeding 15 mph. For this purpose, it is assumed that 15 mph
will not be exceeded by:
a) movements contained within the confines of a yard or siding
b) movements starting from rest, or virtually at a stand at a main stop
aspect
c) movements proceeding under the authority of a position light aspect.

B27.5.4 Performance category 4 equipment
Semaphore main signals shall be designed to be readable at speeds up to
100 mph.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

London Bridge signals question
 

In article . com,
writes
On the subject of theatre type indicators, was there anywhere else,
other than Liverpool Street, that used them with non-alphanumeric
indications? At the ends of the Liverpool Street platforms they used
to display a horizontal line of lights, each light representing a
route from left to right, with a light above and below the route set.
So you had a single horizontal line of lights, except for the set
route which had a vertical line of three.

I think you're misremembering. There were platforms with two routes out,
either left over a crossover and to the starting signal of the next
platform on the left, or ahead and then over a crossover beyond that
signal. These were shown with theatre indicators displaying:

o o
o o o o o o o o o o
o o
o
o
o
o

As for other places, signal P423 on the Down Fast approaching
Peterborough used to have two theatre indicators that were used to
simulate "feathers" - they showed a diagonal line or a horizontal line
for the two routes to the left and the three to the right. This was an
experiment, and they've now been replaced by four normal feathers plus a
theatre to one side that shows (IIRC) "B" for "bay" instead of the third
route to the right.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

London Bridge signals question
 

On Sun, 1 Apr 2007 10:08:13 +0100, Clive D. W. Feather wrote:

In article .com,
writes
And normally known as 'theatre type route indicators'. Except that in
the report into an accident at Euston in 1949, the inspecting officer
describes them as 'a route indicator of the music hall type'.

Was this a generally used term at one time, or is the inspecting
officer simply confused?

This kind of indicator was originally used in music halls or theatres to
indicate which act was being shown; the railway then appropriated them.
So both "music hall type" and "theatre" are reasonable names, though the
former probably went out of use as the music halls did.

Technically they are "alphanumeric indicators meeting sighting
requirement class 2", if I recall correctly. Stencil indicators meet
sighting requirement class 3.

That is the current terminology, which is intended to be technology-independent.

These indicators are now made in fibre-optic form with a single lamp
illuminating many dots via a bundle of fibres, but earlier versions had a
(usually 7 x 7) matrix of "Pygmy" lamps. Depending upon the particular
requirements of each one, each lamp could be used in several indications and the
wiring arrangements could be rather complex and difficult to set up if lamp
proving was required. As well as the semi-colloquial "Theatre", these were also
known officially as "Multi-lamp Route Indicators".

Stencils were different again, with a lamp showing through a mask, behind a
piece of frosted glass, so the indication is hidden until illuminated. Most
people will probably have seen something similar at pedestrian crossings, the
illuminated "WAIT" signs operate on the same principle.

As with MLRIs, Stencils are now (usually) newly provided in FO form, the only
difference between these two types is now their size (physical and indication),
and the number of indications which can be accomodated within a single box.

--
WZR

London Bridge signals question
 

On 1 Apr, 18:12, "Clive D. W. Feather"
wrote:
In article . com,
writes

On the subject of theatre type indicators, was there anywhere else,
other than Liverpool Street, that used them with non-alphanumeric
indications? At the ends of the Liverpool Street platforms they used
to display a horizontal line of lights, each light representing a
route from left to right, with a light above and below the route set.
So you had a single horizontal line of lights, except for the set
route which had a vertical line of three.

I think you're misremembering. There were platforms with two routes out,
either left over a crossover and to the starting signal of the next
platform on the left, or ahead and then over a crossover beyond that
signal. These were shown with theatre indicators displaying:

o o
o o o o o o o o o o
o o
o
o
o
o

As for other places, signal P423 on the Down Fast approaching
Peterborough used to have two theatre indicators that were used to
simulate "feathers" - they showed a diagonal line or a horizontal line
for the two routes to the left and the three to the right. This was an
experiment, and they've now been replaced by four normal feathers plus a
theatre to one side that shows (IIRC) "B" for "bay" instead of the third
route to the right.

--
Clive D.W. Feather | Home:
Tel: +44 20 8495 6138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Please reply to the Reply-To address, which is:

Something similar was in place at Lancaster (up station home signal,
just to the north of the Carlisle bridge) for quite a while, as there
are 6 possible routes available from that - bays 1&2, down platform
loop (3, turnback only), up fast, up main platform (4) and up platform
loop (5). That replaced a pair of theatre indicators, one of which
only lit if the route was towards either of the bays.

GM

London Bridge signals question
 

On Mar 31, 10:59 pm, G wrote:
I've seen RA indicators at Manchester Victoria, where there are no
single manned trains. Are they serving the same purpose?

And, while I'm in obvious (but not to me) question mode, above the
signals are larger ones that occasionally display U B in two boxes.
Why?

According to the 1998 resignalling notice, there is no route
indication "UB" at Manchester Victoria. The indications used there
a

"UF" - Up Rochdale Fast
"DS" - Down Rochdale Slow

"UB" is used on a shunting signal at Philips Park South Junction to
denote "Up Baguley".

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London Bridge signals question
 

On Mar 31, 5:59 pm, "Jonathan Morton"
wrote:

"Peter Masson" wrote in message

Presumably the signal itself uses an LED display, so that
the upper head can display green or yellow, and the lower
head yellow or red, and the signal as a whole can display
all four aspects R, Y, YY, and G.

I think I read somewhere that both heads can display red,
but that normally the lower one is used for red. The upper
head can be used in emergency to display red if the lower
one has failed for any reason. BICBW.

That is wrong. The signals used on the Manchester South scheme can do
that, but they aren't LED type.

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Mileposts: http://www.railsigns.co.uk/other/milepost1/milepost1.html