Communications systems; Data processing systems; Communications apparatus; Computer interface apparatus; Computer networking apparatus; Computing apparatus; Data acquisition apparatus; Data capture apparatus; Data entry apparatus; Data security apparatus; Data transfer apparatus; Digital telecommunications apparatus; Direction finding apparatus; Electronic controlling apparatus; Electronic interface apparatus; Information processing apparatus; Programmable control apparatus; Programmable electronic apparatus; Radar apparatus; Radar jamming apparatus; Radio control apparatus; Satellite communication apparatus; Wireless communication apparatus; Computer modelling language software