Glossary
&
The irreverent term for a complicated control panel.
The "V" shaped brackets on the vehicle under frame used to suspend brake linkages.
The "W" shaped plate connected to the solebar of a wagon in which the axleboxes are suspended.
#
9.5 mm gauge, 2 mm to the ft, 1:152.4 scale.
A
This describes a system of train working whereby only one train is allowed to occupy one stretch of line at any one time. All passenger lines are worked on this principle.
a
A
In DCC: A decoder that is not intended to be installed in a locomotive, but remains in a fixed location and controls accessories such as signals or track switches/turnouts. Also known as &q...
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In DCC: The address is the identification number used by the decoder to identify which communication it must act on. The address is usually unique for each decoder, but this is not a requirement...
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a
proportion of locomotive weight borne by driving wheels.
A
Operating and controlling several locomotives as if they were a single entity by sending speed and direction commands to a common address. Also called decoder assisted consisting. See also...
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Meter which measures current flow in amperes.
The unit of electrical current, generally written as amps.
Conventional track voltage (NMRA Standard S-9) typically varying between zero and tweleve volts for speed control and polarity reversal for direction control.
Voltages and/or frquencies which convey information and are not digital.
a
structure carrying water over depressed ground.
wire-wound rotating bobbin core of electic motors used in models.
wheeled container running on narrow rails between and beneath normal rails for removal of locomotive clinker and ash.
A
More usually this term is used in conjunction with colour light signals. It refers to the indication given by the signal, a red "aspect" for instance, instructs the driver to stop.&nbs...
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The brilliant but, fatally flawed railway propulsion idea pioneered by Brunel. Trains were connected to a sliding piston within a pipe which was laid along the centre of the track and propelled ...
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Abbreviation for Association of Train Operating Companies. Body formed to represent the post - privatisation train operating companies.
Control circuits which sense opposite polarities at rail gaps and automatically reverse the polarity of the rails to allow smooth continuation of the motive power. Applications include: reversin...
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Operation of trains through relay banks, etc, without human.
Abbreviation for Automatic Warning System. A system incorporating electromechanical devices set between the rails which give audible and visual confirmation of signal aspects to a driver in his ...
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A box in which the axle end is located so as to act as a bearing. These were packed with grease for lubrication. Modern axles now have roller bearings.
B
British Railways (1948 - 64), British Rail (1964 - 94). The nationalised UK railway system. Under this, all railways were subject to the central control of the British Railways Board, alth...
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Some locomotive decoders can sense the rotational speed of the motor and automatically adjust future digital pulses to the motor to maintain a desired speed. Also called load - compensating deco...
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b
chippings spread between and around sleepers.
B
The amount of information that can be transmitted between the command station and decoder(s) in a certain amount of time.
This is a mechanical disc signal used to repeat the setting of the signal ahead. They are used when signals are sited in awkward locations, say beyond an overbridge. They are mostly of the...
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Operating and controlling several locomotives as if they were a single entity by sending discrete speed and direction commands to each locomotive in the consist. See also "Consist".
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The name given to "The Reshaping of British Railways" report of 1963. This report heralded the famous railway line closure programme of the mid 1960s.
type of flat-topped firebox on locomotive.
The electrical waveform of digital packets transmitted along the rails is known as a bi-polar signal. Positive pulses followed by mirror image negative pulses are the key characterisation.
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A relay (qv) which will hold in either of two positions.
Colloquial term describing the four big railway companies set up at the grouping in 1923, i.e., LMSR, LNER, GWR, and SR.
A logical value that can be either a one or a zero.
A device, generally electronic (qv) whose function is understood even though its operation remains a mystery.
This describes the "AREA" controlled by a signal box, (sometimes called a block post). It refers to the distance between the previous signalbox's advanced starter signal and the first ...
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b
train made up of identical wagons or vans etc.
B
diesel or electric locomotive having two driven axles, i.e. four driving wheels, on each of two bogies.
Colloquial term often used by railwaymen to describe the arm of a semaphore signal. The "board is off" means that the signal is raised or lowered to the line clear position.
b
a swivelling assembly carrying usually four wheels (sometimes six) mounted below a locomotive or coach.
principal cross-member of a bogie carrying the pivot.
B
A link in a circuit; often a wire linking two parts to ensure electrical continuity.
Barry Railway. Based in South Glamorgan. This was a small but highly profitable concern also carrying minerals.
Based in South Glamorgan. This was a small but highly profitable concern also carrying minerals.
A single support post fitted with two or more individual signals. Junction signal are more often bracket signals
The independently published "all line" railway timetable. First published in the 19th Century.
A metal lever used mainly on wagons to operate the vehicle's brakes manually whilst stationary in sidings.
The vertical support for a guard's handbrake wheel in brake vans.
Short for rail break (qv).
b
usually the last vehicle in a train from which the guard (conductor) can operate the train's brakes if neccessary.
B
A rectifier consisting of four diode elements connected in a square (bridge) formation to provide a reasonably level dc output. see rectifier.
Colloquial term often used by railwaymen to describe the arm of a semaphore sognal. The "board is off" means that the signal is raised or lowered to the line clear position.
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A specially encoded digital packet that will be acted upon by all decoders that receive the packet. Commonly used in service mode programming and for stopping a locomotive in front of a red sign...
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Shockabsorbing device of which two are normally fitted to the ends of rail vehicles. Designed to absorb impact and keep adjacent vehicles from damaging each other.
Lower outer crossmember of a railway vehicle underframe onto which buffers, coupling hooks, brake hoses and cables are fixed. Often, the headstock forms this part of the vehicle.
Frame or fabrication placed at the end of a line to stop vehicles from running off the track.
b
strongly sprung shock-absorbing fittings at each end of all railway vehicles.
coal receptacle at rear of tank locomotive.
B
A set of wires that serves as a conduit for electrical signals and distributes them around the layout.
A colloquial expression originating in the 1980s which describes the provision of buses to replace train services and allow rail closures.
C
A device used by model railroad engineers (operators) to control motive power and accessories by sending electrical or electronic instructions to the locomotive (via the DCC command station).
The bus used for cab - to - command station communication, and vice - versa.
c
separation of layout into indendently - controlled blocks.
U.S. equivalent of guard's van/brake van.
C
A small subsidiary signal, fixed below the main arm which when cleared allows a train to enter an occupied section of line and proceed with caution.
Cambrian Railway. This Welsh company had its headquarters curiously situated in North Shropshire, England!. Its main lines were from Shrewbury to Aberystwyth and Pwhelli. Based on ro...
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This Welsh company had its head quarters curiously situated in North Shropshire, England!. Its main lines were from Shrewsbury to Aberystwyth and Pwhelli. Based on route length and area co...
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c
electric motor with side magnets enclosed in thin metal box, developed originally for slot car racing.
C
A device for storing a charge of electricity.
c
common English term for passenger coach.
gradual relegation of wearing rolling stock to less demanding or pretigious uses.
arrangement of suspended wires for overhead current collection.
the overhang of the centre of a long vehicle on the inside of a sharp bend.
iron castings spiked to sleepers (ties) to secure rails.
C
An impedance, used to damp out ac ripples in a rectified circuit.
Raised longitudinal section of a carriage roof, used to give additional daylight and ventilation for gas lighting. Common in late 19th Century carriage design.
c
roof with central vertical extension the sides of which are glazed.
C
locomotive with three driving axles (six wheels) on each bogie.
c
vehicle for accommodation of passengers (car in U.S.)
contact rubbing on live rail or wire to pass electricity.
C
Term used to describe signals which are electrically operated and use lamps with coloured lenses to display the aspects (see MAS).
The command station receives electrical signals (operator instructions) from the cab. The command station then creates NMRA DCC digital packets in accordance with NMRA spec...
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A system of wiring where a number of controllers, each with its own independent power supply, are connected to a common return rail.
c
contact ring on armature shaft split into segments corresponding to number of windings, receiving current from brushes.
C
A claim made by a manufacturer that their product will generally work with other compatible devices in areas where both devices support a given function.
Same as conformance. A compliant product is one that has passed NMRA tests and earned an NMRA Conformance Warrant.
c
U.S. term for bellows gangway between coaches.
U.S. equivalent of guard, in charge of train.
C
A configuration variable, or CV, is a defined piece of information used by the decoder to adjust its operation. This information is permanently stored inside the decoder until the user wishes to...
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Products that have passed the NMRA's extensive testing procedures are eligible for a Conformance Warrant if the manufacturer also agree to fix any discrepancies that might become apparent in the futur...
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An official document awarded by the NMRA to a manufacturer for a specific product that has demonstrated conformance to NMRA Standards and applicable Recommended Practices by virtue of Passing all appr...
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Heavy section metal rods on a steam locomotive. These transfer the liner tractive force from the pistons into reciprocating motion which turn the driving wheels and propel the locomotive forward...
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A device to connect wires, etc.
Operating and controlling several locomotives as if they were a single entity. For example, several diesels might be connected together to provide more power for a steep grade. Also called...
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A device for completing a circuit, usually in switches and relays (qv). Normally "a pair of contacts" or "contacts".
The bus used for transmitting digital packets from the command stations to power station.
A selection of switches and other devices, mounted on a board, to provide control for a model railway.
A device for controlling the speed, and generally the direction of travel of a locomotive.
Solder in the form of a hollow wire containing flux.
c
device for connecting vehicles into train.
C
Large metal rods that connect the driving wheels of a steam locomotive. Their purpose is to distribute the tractive force to each of the driving wheels.
This Glasgow based firm formed the northern leg of the West Coast Main Line, from Carlisle to its home city. It also owned important routes from Glasgow to Edinburgh, Perth and Aberdeen.
The name given to a design of early express locomotives in which a single axle with two large diameter driving wheels was located at the rear of the locomotive, thus allowing a low slung boiler.
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A railwayman that operates a remote level crossing and who often resides in an adjacent crossing keeper's cottage.
c
pointwork allowing a train to divert to a parallel line.
longer than standard sleeper (tie) beneath point ect.
C
A small bridge or short tunnel provided to take a stream or ditch under the railway trackbed.
The flow of electricity in a circuit.
The amount of electrical flow required by an operating device.
A device for breaking a circuit, should the current flow become excessive. See fuse.
c
excavated channel through rise of ground.
D
Digital Command Control is one of several methods of controlling and/or operating a model railroad layout. The control information is provided in the form of a digital signal instead of a standa...
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An insulated crossing in the track.
d
printed lettering or design which can be transferred to vehicle.
D
A device that receives and acts on digital packets created by the command station. See also "Accessory decoder", "Locomotive decoder", "Mobile decoder", "Stati...
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A device for sensing the presence of a train.
d
another term for bellows or concertina connection.
D
A locomotive powered by a diesel engine which uses an electric transmission system to transfer the power from the engine to the locomotive wheels. Essentially the engine is linked to an alternat...
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A locomotive powered by a diesel engine which uses a hydraulic transmission system (See Torque Converter).
A locomotive powered by a diesel engine uses a mechanical system of transmission. Essentially the engine is linked to the driving wheels through a conventional gear box.
Referring to the replacement of steam locomotives by diesel locomotives and other modern forms of diesel traction.
A digital packet is a defined sequence of bits that instruct the decoder how to respond. See also bit and byte.
An electronic device which only permits current to flow in one direction.
A signal which gives an advanced indication of the setting of the next home signal. Semaphore distants have fishtail ends and since the 1920s have been painted in the familiar yellow colour.&nbs...
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The name for each of the signal posts fitted to a bracket or gantry signal.
d
fitting on top of boiler from which steam is led to cylinders.
D
A track formation which permits trains to travel over a crossing in more than one direction; a complicated device.
d
steam engine where steam is applied alternately to either side of piston(s).
coach etc. with accommodation on two levels.
connection of two locomotives to one train.
complex point allowing crossing other lines with additional rail allowing train to move on to one of several tracks.
D
Double pole, double throw (switch).
Double pole, single throw (switch).
d
early trackless steam locomotive model.
D
The main wheels of a locomotive which provide the tractive force to move the train. Non-driving wheels are called bogie and pony wheels
d
type of wagon body which can be tilted to discharge load.
E
The southern half of the English lines of the former LNER. The Eastern and North Eastern Regions were combined into one in the 1970s.
Abbreviation for the East Coast Main line. Used to describe the line from Kings Cross through York and New castle to Edinburgh and Aberdeen.
Electrically-Erasable Programmable Read-Only Memory. These computer memory devices are used to storedata in a manner that is easily read, but that changes infrequently. Most decoders use E...
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A locomotive powered by electric current which can be picked up from either a 3rd rail or overhead wire. The current is used to drive conventional electric traction motors linked to the driving ...
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e
conductive rod used for quick closing of electric circuits.
E
Electrical circuits involving either the obsolescent thermionic valve or, more commonly, devices including transistors (qv) and microchips (qv).
18.2 mm gauge, 4 mm to the ft, 1:76 scale.
e
built - up track base over dip in ground.
E
e
overhang of long vehicle ends on sharp curve.
U.S. term for engine - driver.
E
Erasable Programmable Read-Only Memory. These computer memory devices are used to store data in a manner that is easily read, but can only be erased and reprogrammed with special tools.
F
The unit of measurement of capacity; very large, hence microfarads are more commonly employed.
A term often used to describe a specific type of route indicator fitted to colour light starting signals. Feathers are rows of small white lamps enclosed in a casing and are fitted to signals wh...
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The electrical input to the controlled rail on a layout.
In DCC: The ability of a device to transmit information regarding its status back to the command station.
f
area of layout, often concealed, where trains can be made up manually etc.
F
In railway terminology, the person responsible for stoking the fire, regulating water levels and maintaining boiler pressure on a steam locomotive.
f
connector between ends of length of rail holding ends firmly in alignment; sometimes erroneously relied on for electrical connection.
extraneous material on moulding where dies were not sufficiently tight together.
platform wagon for self-supporting loads.
F
An electronic circuit which will take up one of two states, and remain so until triggered.
A paste or fluid employed in soldering.
f
locomotive platform for driver and fireman.
F
A railway term used to describe the track, meaning the space in between the running rails, derived from the standard gauge of 4ft 8½ins.
An early attempt at building a "fireless" steam locomotive with the objective of ridding the underground sections of London's Metropolitan Railway of smoke.
f
U.S. term for goods van (also boxcar)
break in rail permitting wheels to cross (in pointwork).
F
The ability to specify (ie map) which function buttons on a cab activate which specific decoder function outputs. This defines which decoder wires are active for each user input.
In DCC A decoder controlled switch that can be turned on and off by a user's cab action.
A device, generally a thin wire, which ruptures should the current flow in a circuit be excessive. See also cut-out.
G
45 mm (1) gauge, scale chosen to suit modelled prototype.
A railwayman who works and maintains the track and the associated permanent way.
Normally used to describe the flexible corridor connectors between carriages that allows passengers to move from one to the other.
g
the actual width, centre width, centre to centre between rails.
G
A committee set up in 1845 to deliberate over the merits of Brunel's "broad" gauge against Stephenson's "standard" gauge.
Formed out of the Long Established MSLR (Manchester, Sheffield & Lincolnshire Railway), it renamed itself upon completion of its main line through to London, via Rugby and the Chilterns.
This famous railway served most of East Anglia, almost having a monopoly of lines heading east out of London. With its HQ at Stratford in the East End, its principal line was from London (Liverp...
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Serving from the north eastern home counties, through Lincolnshire and Nottinghamshire to Leeds. This railway formed the southern half of the East Coast Main Line.
Great North of Scotland Railway. Serving the northern part of Aberdeenshire, as well as Banff and Moray, this small concern had its main route from Aberdeen to Elgin. It also served much o...
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g
U.S. platform wagon fitted with low sides.
train carrying materials, produce etc. (U.S. freight train).
slope or incline, usually expressed as a ratio, e.g. 1: 120.
G
Small marker boards used to indicate the rate at which the track is inclined up or down.
As the name implies these are signals placed at ground level. They can be discs, miniature semaphore arms, or small electric lamps. They are used mainly to signal shunting manoeuvres.
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The 1923 amalgamation of the vast majority of independent UK railway companies into four regional conglomerates. Namely the LMS, LNER, GWR, and SR.
This company's lines ran from Glasgow down the Ayrshire coast south to Stranraer and also via Kilmarnock to Carlisle.
g
official responsible for train, other than driving.
G
Great Western Railway. Unlike other companies, the great Western Railway, which had been incorporated in 1835, merely absorbed the independent Welsh railway companies. Due to their relativ...
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Unlike other group companies, the Great Western Railway, which had been incorporated in 1835, merely absorbed the independent Welsh railway companies. Due to their relatively small size this gro...
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H
16mm, 16.5 mm, 5/8 in gauge, scale nondescript (thankfully obsolete).
h
electronic means of controlling current supply allowing very precise control and full power irrespective of speed.
H
In DCC A portable cab used by the model railroad engineer (operator) to control one or more locomotives. Simple handhelds may have speed and direction controls only. Specialized cabs...
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h
trackwork allowing a locomotive to move away after pulling a train into a terminal platform.
H
The load bearing end cross member of a rail vehicle. Also known as the buffer beam.
16.5 mm gauge, 3.5 mm to the ft, 1:87 scale.
An isolated section used to hold trains in hidden loops, etc. Hertz, the measurement of frequency; in practice, the number of cycles per second.
This refers to the first stop signal that a train encounters when it enters a block section controlled by a signal box. There may also be "outer" home signals in a block section too.
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10.5 mm gauge, 3.5 mm scale.
Colloquial name for hopper wagons. An open or enclosed wagon in which the body tapers at its base and is provided with a bottom door through which the load is discharged.
h
a type of non-scale coupling, reasonably simple to operate.
H
With headquarters in Inverness, this company operated some of the most scenic routes in the UK. Its lines included those to Perth, Keith, Wick and of course the charismatic line to the Kyle of L...
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Hertz, the measurement of frequency; in practice, the number of cycles per second.
I
A quality of a coil of wire which carries an ac or fluctuating current. Its effect is similar in action to a resistance.
A lamp mounted on a panel to provide an indication of the state of a circuit, or a length of track.
A fishplate made from plastic material to provide an insulated joint in the track.
A break in the track, which is insulated to provide isolation.
i
U.S. term for signal box.
layout area allowing operator to walk round all sides.
I
A section of track that can be isolated by means of a switch or similar device.
j
free-ended multi-strand electrical cables plugged in when portable sectionalised tracks are reassembled.
K
In DCC Kilobits per second (alsoKbps) refers to the speed of data transmission on various buses. For example 2.2Kbps transmission passes data at 2200 bits per second. See also bus an...
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A type of switch formerly used in telephone exchanges, frequently provided with a large number of contacts.
L
The Liverpool and Manchester Railway, opened in 1830, this is accredited as being the first public, steam powered passenger carrying railway in the UK.
Based in Manchester, it had a busy trans-Pennine network, linking Lancashire and the industrial areas of Yorkshire.
l
arrangement of parallel rows of siding.
L
In DCC Local Area Network is a computer term referring to the interconnections by which various computers and devices communicate with each other in a geographically small location.
A relay which remains held even when its operating current no longer flows.
l
carrying wheels ahead of driving wheels on locomotive.
L
Light-emitting diode, an electronic device which emits a small amount of light when current passes through it.
Area of land immediately surrounding and adjacent to a railway line.
l
consistent colour scheme employed by railway to identify/pubblicise their locomotives and other rolling stock, vehicles etc.
L
London Midland Region. This was basically the English routes of the LMS combined with the ex - LNER lines west of the Pennines. Later (in 1964) expanded to include ex - GWR lines north of Banbur...
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Normally tagged the LMS this was the largest of the largest of the Big Four. Its territory, mainly centred to the north and west of London, stretched from the far north of Scotland and north wes...
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Second largest of the groups, this railway covered the eastern side of country, north of the Thames, through to Edinburgh, and Aberdeen. It also had lines to Manchester and Glasgow and included ...
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Second largest of the groups, this railway covered the eastern side of country, north of the Thames, through to Edinburgh, and Aberdeen. It also had lines to Manchester and Glasgow and included ...
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Centred on Crewe, its main lines ran from London, out to Birmingham, Holyhead, Liverpool, Manchester and Carlisle. The LNWRs main line from Euston to Carlisle is now West Coast Main Line.
l
the physical dimensions which will pass safely through tunnels, past other trains etc. of a specific railway, also the light metal frame suspended from an arm which checks dimensions.
L
A decoder intended for controlling a locomotive (or other similar device). See also decoder, and mobile decoder.
Any voltage below 50V, more commonly between 3 V and 24 V.
London and South Western Railway. This company's main line ran from Waterloo to Portsmouth, Southampton and Exeter. It also owned an extensive suburban network to the west of London and a ...
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M
In DCC A sequence of user - definable commands, that is accomplished with a single button press.
Abbreviation for Multiple Aspect Signalling: The correct term for modern electrically operated colour light signals which can show Red, Amber, Double Amber and Green aspects.
A measuring device; in electrical circles, a means of measuring the voltage or current in a circuit.
An ingenious device which contains a mass of specialized electronic circuits; more correctly termed an integrated circuit.
m
minute integrated electronic circuits.
M
A miniaturized, self-contained, computer on a single chip. The computer's operating instructions are also stored in this self-contained chip.
A specialized microchip which forms the heart of a computer and can also be used in control circuits. Fiendishly complicated but frequently very cheap.
A switch which makes contact with a very small movement of the operating mechanism.
In DCC One thousandth of an ampere. One thousand milliamperes (mA) equals one ampere. See also ampere.
In DCC One thousandth of a second. One thousand milliseconds (mS) occur every second.
In DCC A decoder that is designed be able to properly work if installed in a device that moves around the layout using rotating wheels on tracks. See also decoder.
Published in 1955. This was a grand plan outlining how the country's railway network was to be re-equipped and revamped to meet the challenges of post-war Britian. Chief amongst its propos...
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m
raised central roof extension like a clerastory but without windows.
complex for servicing and readying locomotives.
M
A device for turning electrical energy into rotary (or occasionally,reciprocating) motion.
An early term used for drivers of diesel or electric propelled locomotives or units and trams.
Centred on Derby, this company's lines radiated from there to London, Carlisle, Manchester and Bristol.
Wire containing a large number of separate cores, each identified by colour coding.
A plug with a number of pins, handed so that it can only be inserted one way; used to connect cables to baseboards, ect.
A series of rotary switches advanced step by step by means of a solenoid-actuated ratchet mechanism.
A test meter provided with probes and a means of switching between various ranges to measures volts, amperes and ohms.
m
electric light signals (red, amber, green).
M
Passenger carriages, some with underfloor engines and Driving cabs, which are designed to couple together with others of similar type and be under the control of one driver. A separate locomotiv...
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N
9 mm gauge, :160 scale (2 1/16 mm scale, 1:148 British N scale).
The merging of all UK railways into one state owned company. This occurred on the 1st January 1948 with the birth of British Railways.
North British Raileay. Like the Caledonian, based in Glasgow. It had an extensive network in Scotland, owning the Berwick to Edinburgh and Aberdeen lines. Further N.B. routes include...
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Like the Caledonian, based in Glasgow. It had an extensive network in Scotland, owning the Berwick to Edinburgh and Aberdeen lines. Further NB routes included the West Highland line to For...
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Strictly, neon tube, a specialized detector lamp, generally used in mains voltages.
North Eastern Railway. This company had a near monopoly of the lines in the North East with its main line forming the central part of the East Coast Main Line north of Doncaster to Berwick.
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The National Model Railroad Association is an Organization of volunteers that, among other things, created the NMRA/DCC Standards and Recommended Practices. For membership information, call +1-4...
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As well as the lines of the ex - NER, this region included some routes of the former LMS, plus the more northerly ex - GNR lines transferred into the ER during the 1960s.
O
32 mm gauge, 7mm to the ft, 1:42.5 scale.
16.5 mm (OO/HO) gauge, 7 mm scale.
o
passenger coach with extra facilities for viewing scenery.
O
In DCC: A device that senses the presence of a train on a section of track. Also known as a block occupancy detector.
A small ungated level crossing, or bridge, provided to maintain access for farmers whose land was bisected when the railway was built. They are not public rights of way.
The unit of electrical resistance.
16.5 mm gauge, 4 mm to the ft, 1:76 scale.
o
from a passenger car with railed balcony at rear.
O
The process of changing the decoder's CV's while the decoders are operating on the layout, instead of on the programming track. This method of programming decoders does not interfere with the op...
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The term used to describe the system of masts, insulators and contact wires used on railways using electric power delivered by an over head conductor wires. Also known as catenary.
The system of current collection used for most prototype electrified railways. Can be modelled using commercial or home-made equipment, but involves considerable additional work.
P
18.83 mm gauge, 4 mm to the ft, 1:76.2 scale.
One method used for programming of decoder CVs. It is a method of accessing the configuration variables four variables at a time. Each set of four variables is called a page. Se...
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p
tank locamotive carrying water supply in side tanks.
P
Insulated frame fitted to the roof of an electric locomotive or unit and used to collect current from the overhead contact wire.
A nickname given to the 19th century trains that the railway companies were, by law, obliged to run to cater for the less affluent. They stopped at all stations and were consequently slow. The f...
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Method of controlling block section in which more than one train can be allowed in one block section. Mostly used on goods lines, it can sometimes be used in the platform lines of large stations...
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p
locomotive used (usually) at terminal station for handling empty coaches and so on.
U.S. term for leading bogie (truck) on locomotive.
P
The ancestor of the railway track. A system of fixed wooden "rails" which were used to guide truck with wooden wheels which were either horse drawn or manually propelled.
p
(U.S. turn-outs or switches) trackwork allowing a train to change from one set of lines to another or proceed in either of two directions.
P
A variable resistance (qv), generally used in electronic circuits.
The portion of a layout that is powered by a single power station.
A source of electrical power. Commercial power packs might also have controls for conventional analog (NMRA S-9) operation. See also tranformer.
The measure of power of an electrical device, expressed in va (qv) or watts (qv).
A device intended to amplify the low current DCC electrical signals transmitted by the command station for the purpose of providing high current DCC signals with sufficient power to operate model trai...
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A box containing transformer(s) plus rectifiers & controllers; the interface between 240V mains and the layout low voltage supplies.
The generic term used to describe the era of railways prior to grouping of 1923.
The dissolution of the nationalised railway system, breaking it up into individual privatisation was the 1st April 1994.
Insulated prods on the end of flexible leads which are plugged into a multimeter to connect it to the circuits being tested (probed).
A special section of track isolated from the main portion of the layout and used for checking instasllation and for setting the values of the decoder's configuration variables.
Programmable Read-Only Memory. Also OTPROM: One-Time PROM. These computer memory devices are used to store data in a manner that is easily read, but can only be written at the factory befo...
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The definition of the "language" used between two devices. The agreed upon definitions of the packetis format and intended meaning is known as a protocol. The DCC protocol. ...
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The full - sized railway system on which the model is based.
One of the earliest successful steam locomotives. Designed by William Hedley a mentor of George Stephenson, it operated at Wylam colliery in the early 19th Century.
passenger coach with dining facilities and comfortable seats.
The technique of controlling motor speed with voltage pulses of varying time duration (pulse width). The wider the pulse, the more power is provided to the motor, the faster the motor rotates.&n...
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Method of working where a locomotive is coupled to a coach which has driving controls at the rear end, allowing the driver to drive the train from both ends, obviating the need to run round at terminu...
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See pulse width modulation.
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vertical strut supporting wagon/coach substructure.
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The sequencing of items to be processed. A programming technique intended to insure that command stations transmit important digital packets first and less important packets later would be a pri...
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An insulated gap in a rail, used to separate one section from another.
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type of (usually) two-car train running regular local services.
as railbus in countries other than Britain.
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The post - privatisation company charged with maintaining and running the UK railway network infrastructure.
The name of the legislation required before any railway can be built. The sponsors have to prove it's financial soundness and benefits to Parliament to receive approval.
Refers to the great rush and craze to sponsor and build railways which occurred during the mid 19th century in Britian. Many fanciful schemes were promoted through Parliament during the period a...
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Prior to the building of the railway network, many different "time zones" existed across the UK. This however, proved to be unworkable to the railways and so a "standard" was...
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A famous competition held at Rainhill, near Liverpool, in 1829 to test various designs of steam locomotive. Stephenson's Rocket proved the superiority of the simple expansion steam locomotive ov...
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set of coaches made up into a train or part of one.
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This form of computer memory is used to store data in a manner that is easily read and written. Used in command stations and decoders to store information that frequently changes.
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scale drawing of an area of railway including all building, basically for calculation of rates (local taxes) payable.
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A term that describes the cutting back or loss of railway services. The term has been in recognised use since the mid 1930s.
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track for goods trains leading into (but stopping at) station for handling parcels, mails and so on.
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A set of specifications that are only less mandatory than NMRA Standards by virtue of their slightly less critical subject matter. While the inclusion of features described by NMRA DCC Recommend...
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A device for converting ac supplies to dc.
A magnetically - operated switch, enclosed in a glass envelope.
A basic method for accessing the eight most basic decoder CVs. See also paged programming, direct CV programming and operations mode programming.
A series of switches operated by means of a coil magnet.
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pointwork near end of rails in terminus to allow locomotive to depart leaving train at platform.
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This device cleans up the DCC signal timing and provides power to drive additional power stations.
A device which has the effect of limiting the flow of electricity in a circuit. Also used to describe the quality of such a device.
Radio controlled Electronic Tokenless Block. Introduced during the 1980s on lightly trafficked lines, RETB uses radio communication combined with a computer based interlocking system to control ...
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The electrical output from the non - controlled rail on a layout.
The feed, via a DPDT reversing switch, to a reverse loop or triangular junction.
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loop of track returning locomotive to original line in opposite direction, requiring current polarity to be reversed.
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The division, During WW1, of the Ministry of Defence charged with operating military railways overseas. The acronym became the nickname of the ex-military owned, Great Central Railway designed, ...
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the drag of a vehicle or train opposing tractive effort.
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These were set up during privatisation as owners of locomotives and carriages who in turn hired and leased the equipment to the new Train Operating Companies.
Read-Only Memory. Also Mask Programmed ROM. These computer memory devices are used to store data in a manner that is easily read, but can only be written at the time the silicon chip is ma...
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Because early steam locomotives were low powered, pioneering engineers used rope or cable winches powered by stationary steam engines to haul trains up steep inclines. Similarly, the ropes would...
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The act of specifying the desired route for a train and programming the DCC system to properly actuate all turnouts (track switches) automatically when the route is chosen. See also Macros.
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Rhymney Railway. A great rival to the TVR, covering much the same area in South Wales.
A great rival to the TVR, covering much the same area in South Wales.
A rule on many prototype railroads that specifies conditions for lighting and dimming the headlight.
The Large station name boards placed at the ends of platforms.
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7/8 in gauge, 3/16 in to the ft, 1:64 scale.
The Stockton & Darlington Railway. This scheme is accepted as the first public steam operated railway, although initially, it only carried goods traffic.
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a tank engine carrying water supply in tank fitted and curved over the top of the boiler.
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Describes a method of building locomotive frames in which iron plates are bolted around a wooden beam, usually oak, for rigidity.
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the relationship between any dimension of a model and that of its full - size counterpart.
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A wiring diagram where the components and wires are laid out in symbols without regard for their actual appearance or location in the unit.
This consisted of all the former LMS and LNER lines north of the Border.
Silicon - controlled rectifier, an electronic device that is the heart of "chopper" control.
Official title given to a trainee or assistant driver of a diesel or electric locomotives.
South Eastern and Chatham Railway. A joint company formed from the London, Chatham and Dover Railway and the South Eastern Railway. This concern had a near monopoly of lines in the country...
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A switch used to energize or isolate a section of track.
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the older type of signal employing a counterbalanced arm, the position of which instructs a driver.
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One which uses a pivoted arm or board to indicate either a clear road or danger.
This method is used when programming decoders on the programming track. It is characterized by using broadcast packets and a safe power level.
A direct connection across a power supply of negligible resistance, creating overload conditions. Only serious if cut-out or fuse is not provided in circuit.
Similar to a calling on arm, these allow a train to draw forward to proceed with shunting operations.
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(U.S. switching) the arrangement of vehicles into a train.
locomotive used to manoeuvre coaches, wagons and so on, to make up a train in the correct sequence.
track(s) leading into a marshalling area in which they debouch into a number of sidings.
water containers mounted on either side of a tank engine boiler.
tracks of limited length adjacent to main lines, used for shunting, loading/unloading or temporary vehicle storage.
a control centre for all signals affecting a particular stretch of line (U.S interlocking tower). &n...
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A bridge spanning multiple tracks and fitted with several signal dolls, each controlling a specific route.
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type of point allowing crossing or travel on alternative track.
the area between pairs of main lines.
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A special type of decoder that is intended to increase the power available from one conventional locomotive decoder. Slave decoders are quite inexpensive and are very useful in the larger scales...
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heavy wood, sometimes concrete, cross-member supporting track (U.S. tie). Also passenger car with sleeping accommodation.
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A relay provided with a device, generally a capacior (qv), to delay iits release.
32 mm (O) gauge, 16 mm scale.
A small banjo - shaped tag that is placed under a nut to allow a wire to be soldered to the terminal. See tag strip.
The longitudinal load bearing beam of a vehicle's underframe.
A coil of wire around a hallow core; when energized, forms a magnetic frield and draws in an iron or steel core.
Originally consisting of all the ex - Southern Railway routes. Those lines located to the west of Salisbury were transferred into the controlof the Western Region in 1964.
Single pole, double throw (switch).
The DCC SIG was established as a communications vehicle for exchanging DCC information amongst users. Membership is open to the public.
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front of locomotive driving cab with small windows.
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Cab-controllable voltage increments which are used to control motor speed. With some decoders, the output power can be set for each speed step.
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casing concealing upper part of locomotive driving wheels.
flexible strip of wood or metal used to draw curves.
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The official name given to second generation DMUs built during late 1980s. So named due to their rapid acceleration.
Single pole, single throw (switch).
Southern Railway. Smallest of big four and based in an area with little heavy industry. This concern was often thought of as a passenger line, but freight was still impotant, especially ar...
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When a motor is prevented from rotating and its maximum rated voltage is applied, the current draw of the motor is known as its stall current. Typically, it is safest to insure that the stall cu...
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American gauge of 2¼in used in 1906, now obsolete.
NMRA Standards provide the primary basis upon which interchange beween equipment and various North American scale model railroads is founded. Under this requirement NMRA Standards include only t...
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This is the last signal in a block section to be encountered before leaving that particular section.
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point from which main lines spread into several platforms.
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A digital packet that commands a locomotive decoder to stop.
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metal strip reinforcement on wagon or van body.
cross - member between locomotive or bogie frames.
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See multi - selector switch.
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metal connection in centre of each sleeper contacting a wiper beneath locomotive for electrical pick - up, now rarely seen. Also a collection of locomotives.
banking of track in tight curves by raising outside rail.
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A series of solder tags mounted on an insulated strip, used to make connections between units and connecting cables.
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one carrying water and coal supplies on one chassis.
one drawing a separate vehicle (the tender) carrying coal and water supplies in greater quantities.
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An electrical conductor rail fixed parallel to the side of the running rails. This being used on networks electrified using the "third rail" system in which EMUs and locomotives collec...
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System of current collection on model railways (now obsolete) where the running rails form the return and the feed is through a third rail mounted either in the centre or to one side of the track.&nbs...
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US term for controller (qv).
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This is a bar or rod fitted between the "W" irons and used to stabilise the chassis against brake forces.
A wagon designed to be unloaded by either rotating it completely upside down, or by lifting it up at one end. Some modern tippler wagons have special couplings which allow the train to remain co...
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The front end of a point, where the blades and tiebar are situated.
Transmission system notably used in the Western Region's diesel hydraulic locomotives.. Torque converters are a successful part of the "gearless" transmissions used in modern diesel mu...
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U.S. term for signalman manning signal box (interlocking tower).
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The bus used for connecting power stations to track feeder wires.
Of locomotives with electric transmission systems. They may be direct acting or linked through spur gears.
The amount of power that a locomotive can exert "at the rail". i.e. A measure of how powerful the locomotive is.
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unpowered second part of a railcar or railbus.
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A post - privatisation railway company that is franchised to run passenger train services over a given area or set of rail routes within the UK.
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instrument for describing large - radius curves.
original English term for decals (q.v.).
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A device consisting of a number of coils wound around a laminated core which alters (transforms) the voltage of an ac supply.
A semi - conducting device, the heart of modern electronics. Extremely small and deceptively simple, but almost incomprehensible to the layman.
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the horizontal (actually very slightly coned) face of a locomotive tyre.
diagonal brace in underframe of a wagon for example.
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12 mm gauge, 2.5 mm to the ft (USA), 3 mm to the ft (GB), 1:120 (Continental Europe).
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similar to dome, a fitting on the top of a boiler for steam feed.
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Taff Vale Railway. The largest of the South Wales companies, this line served from Cardiff through to Llantrisant, Cowbridge and Aberdare. Its main trade was the carriage of coal and miner...
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The largest of the South Wales companies, this line served from Cerdiff through to Liantrisant, served from Cardiff through to Llantrisant, Cowbridge and Aberdare. Its maintrade was the carriage...
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The near universal system of current collection on model railways. The two rails are insulated one from another, as are the wheels on locomotives and rolling stock.
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The name given to the chassis of a railway vehicle upon which a vehicle body is fitted. It includes the buffer beams and fittings, the solebars, wheels, suspension and brake gear.
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The measure of power output of an ac supply (volts x amps).
Set of rods and levers which operate the valves controlling the steam flow into a steam locomotives's cylinders, allowing it to vary its direction, speed, and power output. Common types used on ...
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closed goods vehicle (U.S. boxcar).
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A resistance which can be varied in value, usually by turning a knob.
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brick structure for ventilating tunnel beneath.
elevated structure carrying road and/or railway across valley.
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The measure of electromotive force. Loosely, the higher the voltage, the bigger the kick.
A meter for measuring volts.
W
The three - pin socket, connected to the mains and, ideally, provided with a switch, used to connect high voltage electrical equipment to the mains supply.
The measure of power output of a dc device (volts x amps). Note that due to quirks in ac supply, va and watts are not exactly identical, even though they are calculated in exactly the same way.&...
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Abbreviatiion for the West Coast Main Line. Refers to the main line route from Euston to Glasgow via Rugby, Preston and Carlisle.
War Department. In WW2 the War Department instigated the production of cheap to build, austerity locomotives to aid the war effort. These heavy freight locomotives were suitable tagged &qu...
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technique of painting simulating normal wear and tear.
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Basically all the ex - GWR lines, although it later lost some of its more notherly routes to the LONDON Midland Region.
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disposition of driving and carrying wheels on a locomotive.
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The distance between the centres of the axles on a wagon, bogie or locomotive chassis.
widely used description of wheel arrangement using numbers of carrying, driving and carrying wheels listed front to rear. Certain common arrangements are referred to by names, e.g. Atlantic 4-4-...
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A group of DCC manufacturers and NMRA members who volunteer their time and expertise to create the many Standards and Recommended Practices that constitute the defining documents of digital packet com...
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6.5 mm gauge, 1:220 scale.