On Wed, 21 Mar 2012 06:01:11 +0000, Roland Perry
wrote:

In message , at 00:08:15 on
Wed, 21 Mar 2012, Charles Ellson remarked:
According to Wonkypaedia, all Solo and Electron transactions
require(d) authorisation :-
http://en.wikipedia.org/wiki/Solo_%28debit_card%29

Which, to get back on topic, is why they weren't accepted on trains and
at most railway stations.

What we haven't yet uncovered is what the equivalent mechanism is for
the under-18's VISA Debit cards which have replaced them.

A quick look round a few bank's websites suggests that if the
transaction is online then the money must be in the account. For
offline it would presumably be something in the card (if there
actually is something) which boils down to the chip, the magnetic
stripe or the card prefix; the first won't work outwith CnPland (and
the banks seem to allow the cards to be used there), the second was
discounted (?) but won't apply if the card does not get swiped and
(without going all the way back through the thread to check) the last
seems to be unproven but there ought to be a few offspring available
for a temporary confiscation of their cards to look at the prefixes. I
do have a sneaking suspicion that to some extent it might work by
making kids believe their cards can't go into the red but without any
certain method of enforcing that while the card is used away from any
communication with the bank.