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glossary:glossary_b [2019/09/05 23:03] – [Bell signals] remove extra line tgerbicglossary:glossary_b [2022/10/10 21:55] (current) – [Booster] add bootloader Bob Vetterlein
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-Back EMF generally refers to the voltage that will appear across an inductor if the current is stopped suddenly and in particular to the voltage generated by the rotation of a motor.\\ +Back Electromotive Force ([[wp>Electromotive_force|EMF]]) generally refers to the voltage generated by the rotation of a motor but also to the voltage that will appear across an inductor if the current is changed or stopped suddenly.\\ 
 [[:glossary:back_emf|Main article]] [[:glossary:back_emf|Main article]]
- 
  
 ===== Baud ===== ===== Baud =====
  
  
-Baud in communications refers to changes per second. In the very early days of MODEMs, for example, each bit sent equaled a single change, so baud equaled bits per second (BPS). The terms were initially interchangable. As newer modulation methods (the way the signal is sent or encoded) came along a baud represented more than one bit per second. For example a single baud may have represented two, three or four bits for each change. From that point forward, baud and BPS were no longer the same, though many people still use the terms interchangably. For the sake of clarity, use BPS to represent the number of bits sent per second. +Baud in communications refers to changes per second. In the very early days of MODEMs, for example, each bit sent equaled a single change, so baud equaled bits per second (BPS). The terms were initially interchangable. As newer modulation methods (the way the signal is sent or encoded) came along a baud represented more than one bit per second. For example a single baud may have represented two, three or four bits for each change. From that point forward, baud and BPS were no longer the same, though many people still use the terms interchangably. For the sake of clarity, use BPS to represent the number of bits sent per second.\\ 
 +[[wp>Baud|Baud]]
  
 ===== BC3 ===== ===== BC3 =====
  
  
-The BC3 is an automatic block control system otherwise known as SuperBloc (QV). It controls the speed of a model train depending on the occupation of the block ahead. If the block ahead is occupied the train will slow to a creep speed and stop at a designated point. Otherwise the train will accelerate to a preset speed. Manual control is also allowed for. Kits for the [[:kits:38|BC3]] and literature about it is available from MERG - TBs T33/0-20.\\  +The BC3 is an automatic block control system otherwise known as SuperBloc (QV). It is a development of and compatible with BloNg (Block oriented N gauge). It controls the speed of a model train depending on the occupation of the block ahead. If the block ahead is occupied the train will slow to a creep speed and stop at a designated point. Otherwise the train will accelerate to a preset speed. Manual control is also allowed for.\\ Literature about it is available from MERG - Technical Bulletins T33/01 to T33/28 although kits have been discontinued.\\
-The BC3 kit is No38 Nos 39 and 40 are a test jig and a setting up kit. Kit instructions for 38 and 39 are available from MERG.\\  +
-[[https://merg.org.uk/merg_resources/superbloc.php|Superbloc]]\\ +
 [[:glossary:blong|Main article]] [[:glossary:blong|Main article]]
  
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-Bell Signals are used as part of a block signaling protocol.+Bell Signals are used as part of a block signalling protocol.
  
 The cadence of the Bell Signals were used to convey information. An example would be two bell rings would mean a train is entering a section and two rings followed by one ring may mean the train is clearing a section. The cadence of the Bell Signals were used to convey information. An example would be two bell rings would mean a train is entering a section and two rings followed by one ring may mean the train is clearing a section.
  
-Though there are some universal bell signals, different railroads at different times have had their own signaling schemes.  +Though there are some commonly used bell signals, different railways at different times have had their own signaling schemes.  
 \\  \\ 
-[[https://signalbox.org/block.shtml|https://signalbox.org/block.shtml]]+[[https://signalbox.org/block.shtml|THE SIGNAL BOX website - Block System]]
  
 ===== BGA ===== ===== BGA =====
 Ball Grid Array; a method of permitting a large number of connections in a smaller footprint for large scale Integrated Circuits.  Ball Grid Array; a method of permitting a large number of connections in a smaller footprint for large scale Integrated Circuits. 
-See https://en.wikipedia.org/wiki/Ball_grid_array+See [[wp>Ball_grid_array|BGA]]
 ===== Bipolar ===== ===== Bipolar =====
  
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-Block control is the philosophy that a railway should be divided into blocks and that no train should normally be allowed to enter a block which is already occupied. This means that each block has a stop signal at which a train is required to wait if the block ahead is occupied. This will be set back 0.25 mile from the start of the next block. Further back there will be a distant signal which informs the driver that he needs to slow because the signal ahead is at stop.\\ +Block control is the philosophy that a railway should be divided into blocks and that no train should normally be allowed to enter a block which is already occupied. This means that each block has a stop signal at which a train is required to wait if the block ahead is occupied. Further back there will be a distant signal which informs the driver that he needs to slow because the signal ahead is at stop.\\ 
 Modern electric signalling systems allow for more variation in slow signals with the a double yellow as a preliminary caution as well as the yellow caution to give two stages of slowing.\\  Modern electric signalling systems allow for more variation in slow signals with the a double yellow as a preliminary caution as well as the yellow caution to give two stages of slowing.\\ 
 [[http://www.signalbox.org/block.shtml|http://www.signalbox.org/block.shtml]] [[http://www.signalbox.org/block.shtml|http://www.signalbox.org/block.shtml]]
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-Block Occupancy (The [[glossary_t#toti|ToTI]] of the real railways) is detected by the electric track circuit which detects the presence of a train by conduction between the rails via the wheels. In the past some leading turnouts had a lock which was applied by treadle on the near approach which applied a local mechanical lock when it was depressed by the passage of wheels.+Block Occupancy In the traditional block sytem of working between signal boxes block occupancy is shown by the block instruments showing "Train on Line". In more modern automatic block systems "Track circuits" are used these work by passing a current through the rails from a supply at one end of the block to relay at the other, train wheels short out the relay to show block occupancy, essentially the relay energised proves that the block is clear. An alternative to track circuits is axle counters which count all axles in and out of block and hence determine the state as occupied or clear.
  
  
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-The Block Oriented N-Gauge (or "BloNg") system was a method for automatic block control developed originally for an exhibition layout by the South-West Area Group of the N-Gauge Society (now the Exeter N-Gauge Railway Modellers). It employed a controller per block, colloquially known as "the BloNg". The MERG superBloc system with its [[:kits:38|BC3]] controller resulted from a collaboration between that Group and the Oxford MRS, who also model in 00. The BC3 therefore now replaces "the BloNg", with which it is electrically compatible. +The Block oriented N-Gauge (or "BloNg") system was a method for automatic block control developed originally for an exhibition layout by the South-West Area Group of the N-Gauge Society (now the Exeter N-Gauge Railway Modellers). It employed a controller per block, colloquially known as "the BloNg". The MERG superBloc system with its [[:kits:38|BC3]] controller resulted from a collaboration between that Group and the Oxford MRS, who also model in 00. The BC3 therefore now replaces "the BloNg", with which it is electrically compatible.
- +
- +
-[[https://merg.org.uk/merg_resources/superbloc.php|Superbloc]]\\  +
-[[http://www.ngaugesociety.com/index.php?page=area-groups|http://www.ngaugesociety.com/index.php?page=area-groups]]\\ +
 [[:glossary:blong|Main article]]\\  [[:glossary:blong|Main article]]\\ 
  
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 A Booster in DCC is a second power supply to increase the power available from the main master power supply. This may also have the facility for voltage inversion to allow for reverse loops etc but this is more cheaply handled by a specific reversing module. It can also help to reduce potential damage and problems by being used to divide the whole layout into separate sections each supplied by a booster so that shorts in one section do not affect another and the potential current is reduced to that available from one booster. A Booster in DCC is a second power supply to increase the power available from the main master power supply. This may also have the facility for voltage inversion to allow for reverse loops etc but this is more cheaply handled by a specific reversing module. It can also help to reduce potential damage and problems by being used to divide the whole layout into separate sections each supplied by a booster so that shorts in one section do not affect another and the potential current is reduced to that available from one booster.
  
 +===== BootLoader =====
 +
 +The majority of [[glossary:glossary_m#microprocessor|Microcontrollers]] available today have [[glossary:glossary_f#flash_memory|Flash Memory]] as their program storage. A **BootLoader** is a special section of program, stored in a protected area of memory, which can overwrite any area of memory except its own. By this means the [[glossary:glossary_p#pic|PICs]] used in the [[glossary:glossary_c#cbus|CBus system modules]] can have their firmware updated via the BootLoad facility of the [[glossary:glossary_f#fcu|FCU]]. The [[glossary:glossary_a#atc|ATC Automatic Train Controller]] has a similar arrangement but requires a Bootloading attachment.
  
 ===== Bps ===== ===== Bps =====
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-    * Unordered List ItemBuffers are allocated by various processes to use as input queues, etc. Most of the time, buffers are some processes output, and they are file buffers. A simplistic explanation of buffers is that they allow processes to temporarily store input in memory until the process can deal with it. +    * Buffers are allocated by various processes to use as input queues, etc. Most of the time, buffers are some processes output, and they are file buffers. A simplistic explanation of buffers is that they allow processes to temporarily store input in memory until the process can deal with it. 
-    * Unordered List ItemCache is typically frequently requested disk I/O. If multiple processes are accessing the same files, much of those files will be cached to improve performance (RAM being so much faster than hard drives), it's disk cache.+    * Cache is typically frequently requested disk I/O. If multiple processes are accessing the same files, much of those files will be cached to improve performance (RAM being so much faster than hard drives), it's disk cache.
  
 In Hardware a buffer is a digital or analog stage used to isolate a signal source from the following circuit's loading. This might be the case in Digital where a single output is required to fan out to multiple inputs. In analog it is usually the means to connect a high impedance signal source to much lower impedance circuits, normally with unity gain. In Hardware a buffer is a digital or analog stage used to isolate a signal source from the following circuit's loading. This might be the case in Digital where a single output is required to fan out to multiple inputs. In analog it is usually the means to connect a high impedance signal source to much lower impedance circuits, normally with unity gain.
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-    * Buses are used for connecting components of a computer: a common example is the PCI bus in PCs. See [[https://en.wikipedia.org/wiki/Bus_(computing)|computer bus.]] +    * Buses are used for connecting components of a computer: a common example is the PCI bus in PCs. See [[wp>Bus_(computing)|computer bus.]] 
-    * Buses are used for communicating between computers (often microprocessors). See [[https://en.wikipedia.org/wiki/Bus_(computing)|computer bus.]] +    * Buses are used for communicating between computers (often microprocessors). See [[wp>Bus_(computing)|computer bus.]] 
-    * Buses are used for distribution of electrical power to components of a system. The (usually) thick conductors used are called busbars. In an electrical laboratory, for example, a bare bus-bar will sometimes line the wall, to be used by the engineers and technicians for its high electrical current carrying capacity, which allows a convenient approximation to zero voltage, or ground in the US, and earth in the UK. See [[https://en.wikipedia.org/wiki/Busbar|BUSBAR]]\\  +    * Buses are used for distribution of electrical power to components of a system. The (usually) thick conductors used are called busbars. In an electrical laboratory, for example, a bare bus-bar will sometimes line the wall, to be used by the engineers and technicians for its high electrical current carrying capacity, which allows a convenient approximation to zero voltage, or ground in the US, and earth in the UK. See [[wp>Busbar|BUSBAR]]\\ 
- +
- +
-In analysis of an electric power network a "bus" is any node of the single-line diagram at which voltage, current, power flow, or other quantities are to be evaluated. These may or may not correspond with heavy electrical conductors at a substation. +
  
 =====Byte===== =====Byte=====
 The byte is a unit of digital information that most commonly consists of eight bits, representing a binary number. Historically, the byte was the number of bits used to encode a single character of text in a computer[1][2] and for this reason it is the smallest addressable unit of memory in many computer architectures. [[wp>Byte|Byte]] The byte is a unit of digital information that most commonly consists of eight bits, representing a binary number. Historically, the byte was the number of bits used to encode a single character of text in a computer[1][2] and for this reason it is the smallest addressable unit of memory in many computer architectures. [[wp>Byte|Byte]]
  
glossary/glossary_b.1567724593.txt.gz · Last modified: 2019/09/05 23:03 by tgerbic

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