Keith and Paul,

Thanks for the comments - I've been a bit busy
and away from my desk recently. Also, as you may
have seen I'm trying to sort out why the
decoding sometimes falls over.

Yes, plotting the obs would be the next logical step.
I'm thinking about how I could get as many obs plotted as possible
- possibly by having a large map and scrolling over it
as per the BBC TV forecasts?

Roger