 Jones, Assistant Director of Intelligence (Science) at the Air Ministry.Jones's department, drawing on information from air reconnaissance, PoW interrogations, resistance agents in France and Belgium, Enigma cipher decrypts and the monitoring of radio traffic and radar signals by RAF ground stations and specially equipped bombers known as Ferrets, had built up a detailed knowledge of the German air-defence system.The was similar in signal to the original Bruneval , operating at 560 MHz, but it was more precise and longer-ranging due to its more powerful transmitter and its much larger reflector dish.