Many thanks for your post "Storchy Neil" having had along discussion with Alf on the telephone a couple of nights ago he advised how he fixed the problem so next time I go to the aeroplane I will investigate further.
It will be some time as I am going away for a month.
Neither Alf or myself could get much information from the Tecnam technical manual, they could be a bit more useful ! I will have another look when I have time.
Mank thanks