I seem to remember there was an occurence where the TWR controller passed a noise reading that was a round number to an aircraft, (possibly an N reg WOBUN departure). The aircraft then replied that he was climbing to the noise reading figure and ‘going to London on 12*.**’ . There was then a mad rush to let the LATCC radar controller know he was about to have a level bust! This may have happened to CJF but then again I could well be mistaken. There was, (I think), a long period where the display equipment went U/S and it seemed to just peter out.....Much to many of the Controllers relief..