Mizter T wrote:

Next time I'll buy a carnet from the machine myself - at the other end
of the metro journey I had a quick chance to check out the machines.
From what I remember - but I might be wrong - the RER machines (as
opposed to the Metro ones) didn't sell single Metro tickets but did
sell a carnet of 10. I'm not sure how long they remain valid for,
though I could easily find out I'm sure.

The ones in my wallet must be at least a year old, and worked a barrier
a couple of weeks ago. I bought a job lot to save the game of "hunt the
working machine" each time I arrive at Paris Nord.

On the rare occasions when I needed an NR ticket at King's Cross, I used
to wander over to St Pancras where the queues were shorter. I guess that
doesn't work any more :-)
--
Arthur Figgis Surrey, UK