Thanks for your help everyone much appreciated .

Mike i think the servo is a futaba s3050 digital

one other problem i have after plumbing all the airlines up is that when the gear is out my jettronic air up air down valve seems to be just releasing the air slowly through the exhaust port but when retracted the system holds the air. is this a faulty valve or have i done something wrong. all the sequencing is right but it just passes air when gear is down ??? anyone any ideas ?

Rob.