Barbara Dunn and Nell Corry were two of the pioneering women of British amateur radio, particularly notable because they became licensed at a time when almost all radio amateurs were men.
Barbara Mary Dunn, G6YL (1896–1979) was the first British woman to qualify for an amateur transmitting licence, receiving the callsign G6YL in 1927. Her interest began when her father bought a wireless set in 1923. Interference from Morse transmissions made her curious, so she taught herself Morse by listening to ships and coastal stations. Within a few months, she could copy around 20 words per minute.
Barbara built much of her own transmitting and receiving equipment and operated initially from Stock, Essex, later from Northumberland. She was particularly devoted to CW (Morse) rather than voice operation and became highly accomplished at DX communication. In 1930, she won the RSGB's Committee Cup for her work in 1.7 MHz tests, becoming the first woman to hold an RSGB trophy.
Barbara’s radio work became far more serious during the Second World War. She was one of roughly 1,500 Voluntary Interceptors recruited to listen for suspicious and enemy radio transmissions for the Radio Security Service. Their intercepted Morse traffic ultimately fed into Britain's wartime intelligence system.
Nell Corry, G2YL (1907–1974) followed Dunn and became Britain's second licensed female radio amateur in 1932. She operated from the Tadworth/Walton-on-the-Hill area of Surrey and was another highly skilled Morse operator and experimenter who constructed much of her equipment herself.
Nell Corry became especially famous for experiments on the then relatively unexplored 10 metre band. Radio propagation on that band depends heavily on solar activity, and Corry became adept at exploiting favourable conditions. In 1935 she contacted stations on all six inhabited continents on 10 metres in only six hours and twenty minutes, an exceptional achievement at the time. She was also among the very earliest amateurs, and the first woman, to establish a 10 metre contact with Australia.
Like Dunn, Nell Corry also served as a Voluntary Interceptor during the Second World War, using her ability to recognise and accurately copy Morse transmissions as part of Britain's Radio Security Service operation. There is an interesting connection between the two. For several years, Barbara was alone as Britain's female radio amateur. Nell's arrival in 1932 literally doubled the number.
They subsequently knew one another and were colleagues in amateur radio. Surviving historical material describes Corry as a friend and colleague of Dunn. Their callsigns are also memorable: G6YL and G2YL. In amateur-radio terminology, YL means ‘Young Lady’, the traditional abbreviation for a female amateur operator. In Barbara Dunn's case the letters were particularly appropriate, and she later joked in old age that perhaps her callsign ought to become G6OG, ‘Old Girl.’
Their stations are especially interesting because both women achieved remarkable results with equipment that was largely home-built, low-powered and manually operated. Barbara Dunn built most of her own transmitting and receiving equipment. One of her surviving transmitters is a single-valve tuned plate, tuned grid transmitter, covering roughly 23 to 46 metres. It replaced an earlier split-Hartley oscillator she had used. The valve itself generated the RF with separate tuned circuits in its grid and anode circuits. The operator had to tune those circuits manually, watching the valve current and adjusting variable capacitors and coils to get the transmitter operating efficiently.
Barbara was primarily a CW operator. She could send around 25 words per minute when she qualified, more than twice the licensing requirement of the period. Her antennas appear to have been conventional wire aerials. Consequently, successful DX depended heavily on operating skill, propagation knowledge and patience.
We know considerably more about Nell Corry's station at the time of her famous 10 metre work. A contemporary description says her transmitter was a ‘4-stage crystal-controlled affair’ capable of operating on 40, 20 and 10 metres. By using crystal control, Nell had a substantially more stable transmitted signal than an uncomplicated self-excited oscillator.
The likely set-up was probably: Crystal oscillator, frequency multiplier/buffer stages, RF power amplifier, and aerial. To reach 28 MHz, an oscillator could be operated on a lower crystal frequency and its harmonics multiplied through succeeding stages. This was a common solution because crystals directly operating at the desired HF frequency were not always practical.
A 1936 account records her communicating with Australia on approximately 10 metres using only 50 watts. Nell's extraordinary 10 metre day. On 27 October 1935, Corry used this station to work all the inhabited continents on the 10 metre band in 6 hours 20 minutes. Accounts give contacts including:
- 09:00 — Assam, India
- 10:30 — Queensland, Australia
- 11:00 — Uruguay
- 14:05 — Algeria
- 15:20 — Florida
Her Morse key for this event was itself interesting, a substantial Muirhead double-current key dating from 1915, originally manufactured for British Government use during the First World War. She continued using that key for decades.
Barbara Dunn, Nell Corry and fellow experimenters were also noticing something technically important: changes in radio noise and propagation associated with solar activity. Later accounts describe Dunn, Corry and Dennis Heightman, G6DH, recognising that certain daytime radio noise was associated with the Sun. This was years before solar radio astronomy became an established discipline.
So they weren't merely collecting distant contacts. They were participating in the period when amateurs were helping discover how HF propagation behaves.