On Sat, 27 Dec 2003 12:27:09 +0000, Jim wrote:

I currently have an annual travelcard for Zones 2,3,4,5 and travel
between Harrow on the Hill and Highbury & Islington, using the North
London Line from West Hampstead or Finchley and Frognal. I understand
the idea that the Oyster will be "clever" and deduct credit if I go
into Zone 1 but if I beep my new Oyster in at Highbury, there is no
NLL to beep in out of, beep it in at West Hampstead Jubilee and out
at Harrow Met, how will it know I have used the North London Line?

But if you are a Travelcard holder you do not *need* to beep in and out
in order for value to be deducted (because no value is deducted) when
you are travelling inside your zones. If such a rule was in place then I
agree that every National Rail station in London would have to have
readers but they do not.

Your example shows that you have a valid ticket for your whole trip -
you will enter a gate at Harrow, exit at West Hampstead, pop across the
road and just walk in, catch your NLL train and exit at Highbury. One
trip is recorded for the Tube but the gate at Highbury will simply let
you exit without doing anything to your Oyster Card - simply because
your ticket is valid at Highbury! It is entirely possible to end up at
Highbury gateline having used all sorts of bits of National Rail
services and buses between West Hampstead and Highbury - all of which
are valid trips on a 2-5 Travelcard.

Will it assume I have gone via Kings Cross and charge me an extension
ticket. Alternatively, if I am going via central London (if I miss a
NLL or it's late) and I go via Kings Cross will I get charged twice as
I go through 2 sets of barriers - Higbury to Kings Cross and Kings
Cross to Harrow?

If you go this way then you will be charged because you hit a gateline
twice. However the technology is clever enough to ensure you only get
charged once from your pre-pay part of your card for a trip via Zone 1.
I did some of the early thinking on how the system logic would work via
this sort of interchange.
--
Paul C


Admits to working for London Underground!