Mind you, I've heard replies from pilot's mistakenly told, by a flustered controller to squawk a code with 8 in it, along the lines... "Err the box only seem to go up to seven, I'll snag it on landing"
SSR sends out a pattern of up to twelve pulses in reply to interrogation, that are read as a binary code e.g Code 7031 would be 111 000 011 001... a bit like a barcode?
Last edited by Pierre Argh; 1st August 2006 at 19:44.