glossary:glossary_d
Differences
This shows you the differences between two versions of the page.
Both sides previous revisionPrevious revisionNext revision | Previous revisionNext revisionBoth sides next revision | ||
glossary:glossary_d [2015/01/09 03:13] – [DC] slight wording change Wayne | glossary:glossary_d [2019/08/16 06:08] – Improve explanation beyond "traditional". Acemason | ||
---|---|---|---|
Line 12: | Line 12: | ||
===== DC ===== | ===== DC ===== | ||
- | Direct Current. DC is the unidirectional flow of electric charge. Direct current is produced by sources such as batteries a model train set controller or a dynamo on your bicycle. Typical DC voltage values used on model train layouts are 12V (motive power), 5V (logic circuits such as those used by CBus) and 2-3V (Light-Emmitting Diode ([[glossary: | + | Direct Current. DC is the unidirectional flow of electric charge. Direct current is produced by sources such as batteries, a model train set controller or a dynamo on your bicycle. Typical DC voltage values used on model train layouts are 12V (locomotives and Printed Circuit Boards ([[glossary: |
More information about DC: [[https:// | More information about DC: [[https:// | ||
Line 19: | Line 19: | ||
- | DC or direct current, usually from a 12v supply, is the traditional method of controlling and powering model locomotives by varying the voltage supplied to the track. | + | The traditional method of controlling and powering model locomotives |
- | + | * You already have a DC/analogue controlled layout and/or a lot of non-DCC locos. | |
+ | * You enjoy/ | ||
+ | * don't want to pay someone else to provide circuitry | ||
+ | * want to avoid the complexity of fault-finding in DCC. | ||
+ | * are attracted by the challenge of making a model railway perform well. | ||
+ | * The DCC learning curve looks daunting. | ||
+ | * The potential lack of freedom with DCC. There will be a procedure prescribed for most things that you want to do. | ||
+ | * The potential extra cost of DCC hardware, software and support. | ||
===== DCC ===== | ===== DCC ===== | ||
Digital Command Control. DCC systems allow you to simulate prototypical train operation on your model railroad. With DCC you can operate multiple locomotives independently at the same time on the same section of track without a computer and without blocking or other complex wiring schemes. DCC systems use digital data packets to communicate commands to decoders that control locomotives and turnouts on the railroad. | Digital Command Control. DCC systems allow you to simulate prototypical train operation on your model railroad. With DCC you can operate multiple locomotives independently at the same time on the same section of track without a computer and without blocking or other complex wiring schemes. DCC systems use digital data packets to communicate commands to decoders that control locomotives and turnouts on the railroad. | ||
+ | |||
+ | |||
+ | ===== Debounce ===== | ||
+ | |||
+ | |||
+ | Most mechanical switches and relays have springy contacts that can bounce when thrown. This will deliver multiple pulses to the electronics and play havoc when a circuit or software only wants to see one pulse or step in the signal. The classic cure is to add a delay of several 10s of Milliseconds after the first step so repeats can be ignored. The delay length can vary according to known switch parameters. Nowadays that is most easily done in the software and is typically called Debounce delay. | ||
+ | For hard-wired logic in CMOS, TTL etc, with no software, the usual method of trapping bounces is to add a bistable between the switch and main input. | ||
Line 49: | Line 62: | ||
- | Digitrax is a sullpier | + | Digitrax is a supplier |
Line 61: | Line 74: | ||
The DIODE is an electronic component that allows the passage of current in only one direction. | The DIODE is an electronic component that allows the passage of current in only one direction. | ||
+ | |||
+ | ===== Dirty PSU ===== | ||
+ | " | ||
+ | |||
+ | If the feed wires from PSU to load are of sufficient length to have a bit of impedance and supply several loads, then the dirt caused by one load can cross to other loads. This would usually be positive & negative sharp spikes superimposed on the dc. If the PSU is inadequate and feeds clean and dirty loads then the effects can also cause Pic ( or other microprocessor ) " | ||
+ | |||
+ | The separation of the digital low current circuitry with a separate " | ||
+ | |||
glossary/glossary_d.txt · Last modified: 2024/03/10 11:55 by mike_randall