'As Australia entered World War II, its all-male armed services had a problem only a woman could solve. That woman was Violet McKenzie, Australia’s first female electrical engineer, a wireless radio pioneer, one of the ABC’s first broadcasters, and the founder of the volunteer Women’s Emergency Signalling Corps, or “Sigs”. Established in 1940, Sigs trained hundreds of women to the highest standards in Morse code and semaphore using a unique system McKenzie devised herself, drawing on mnemonics and musical cues. She also instructed her students in circuit theory and the physics of electromagnetic radiation and taught them how to fix radios and install antennas. The “girls” of Sigs practised military drills at weekend camps and in Sydney’s Centennial Park, the top students wearing the uniform that McKenzie, whom they adored, had designed herself. Australia’s military was in urgent need of personnel with mastery of signalling technologies; it turned to Sigs for help.' (Introduction)
