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Old January 10th 05, 12:21 PM posted to uk.transport.london,cam.transport
Clive D. W. Feather Clive D. W. Feather is offline
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First recorded activity at LondonBanter: Jul 2003
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Default Cambrige - London traffic up 75%

In article , Michael Bell
writes
Where a branch line diverges from a main line, as at Hitchin, when idle
and no train is immediately expectd. the points normally return ("default" it
would be called in computer terms) the straight ahead main-line setting.


That's called "self-restoring" and it is *NOT* the normal arrangement.
Indeed, if you watch at Hitchin you can see it not happen.

There are a few places where points are made self-restoring. There are
rather more cases where points may move for a not-immediately-obvious
reason. For example, at crossovers - the links between adjacent tracks -
it is normal for both ends to move at the same time. So the points at
the end of the northbound platform at Hitchin have to be set for
Peterborough before a northbound fast train can go through, even though
it doesn't cross them. There are more complex layouts where the
relationship is less obvious, but it's there nevertheless.

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