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B2125 Pedal generator, brass / steel / paint, designed by Alfred Traeger, unknown maker, used by the Flying Doctor Service, Cloncurry area, Australia c 1930 - 1940. Click to enlarge.

Traeger Pedal generator used by the Flying Doctor Service

  • c 1930-1940
The Traeger pedal generator is part of the Powerhouse Museum's Communications Collection and is an important Australian innovation. Alfred Traeger, a South Australian electrical engineer, developed this power-generation system for two-way wireless radios in the 1930s.

Pedal-powered radios brought a significant change to life in remote areas by providing help in emergency medical situations and diminishing the loneliness of the inland world. They were integral to the development and success of the AIM Aerial Medical Service (later known as the Royal Flying Doctor Service). The Traeger pedal represents a significant milestone in the history of communication in Australia.

This set of pedals, dating from the 1930-40s, is a second series generator. The first pedals were designed by Traeger in 1928 for Reverent John Flynn's Australian Inland Mission (AIM) project.

In the early 20s Reverend John Flynn, a missionary of the Presbyterian church's Australian Inland Mission, was very concerned about the quality of people's lives in remote parts of Australia, and in particular their access to medical services. He determined to establish a service - which he called the 'mantle of safety'- to provide not only medical aid in emergencies but also a break from the isolation that was so characteristic of life in the bush.

Rev John Flynn was a keen radio enthusiast and he believed that radio - a new emerging technology in the 1920s - was the solution to the problem. In 1926 Flynn recruited Alfred Traeger, a young South Australian electrical engineer and a 'radio wizard', and together they furthered Harry Kauper's initial experiments and designs. In November 1926 they established the first communication by Morse code between Alice Springs and the Hermannsburg Mission, a distance of 140 kilometres, opening up the way for continuous wave transmission in the bush.

The major obstacle to a wider network was that these radios were powered by batteries. The batteries were glass Edison copper oxide batteries, expensive, cumbersome and unreliable. They were full of acid. Traeger felt that they were a potential hazard to the families in the stations, that they would be unsuitable for the tough inland conditions and unlikely to survive a journey to the outer stations. As an alternative Traeger developed a compact hand-cranked generator. But this was not the most efficient solution as the radio required two operators - one to crank the generator and the other to send the Morse code.

Inspired by Flynn's vision, Traeger continued refining the radio equipment to make it more usable, portable and durable. He developed a transceiver, combining the transmitter and receiver into a single unit and redesigned the generator to be powered by bicycle pedals. With the generator bolted to the ground and connected to the transceiver, the operator could now generate comfortably 20 watts of power at about 300-400 volts with his feet, and leave his hands free to operate the radio itself. In November 1928, Traeger presented the new pedal-powered radio to Flynn who replied: "Go home and get your Sunday suit. I want to take a very important photograph". The photograph of Traeger operating the pedal wireless is now historically famous.

On 19 June 1929 the Augustus Downs station in Queensland used the first pedal-powered radio to send a signal to the base station at Cloncurry, 320 km away. The message read: "Greeting by wireless service from Augustus Downs first station installed. Manager, family and station deeply appreciate service rendered, Rothery, Manager". In a letter written to Fred McKay, Mrs Rothery, aged 92, remembered: "With the pedal wireless […] we were able to call up the Flying Doctor and even send messages and telegrams, it was the biggest thing that ever happened in my life in the bush. So Mr Traeger will always be our special friend. The pedal wireless saved our lives."

The pedal sets were installed in other outstations in Australia to provide instantaneous communication with base stations up to 1,500 km away. This was the beginning of the Australian Aerial Medical Service, later known as the Royal Flying Doctor Service still in operation today.

It became quickly apparent that using Morse code was an issue for people on the stations, causing many mistakes and misunderstandings as a result. In 1931 Traeger came up with the solution: he developed an automatic Morse code keyboard which, used like an ordinary typewriter, converted the letters into the correct Morse code signal. Knowledge of Morse code was no longer necessary.

Traeger's pedals were used throughout the 1930s and by 1939 were replaced by vibrator units and later by voice-operated systems.

The pedal-powered radios also played a crucial part in the establishment of the 'School of the Air, in Alice Springs in 1951. Using pedal-powered radios and the Flying Doctor large radio network across the outback, the 'School of the Air' was able to provide distance education programs to children in isolated stations and regular contact between pupils, home tutors and teachers. The 'School of the Air', renamed 'School of Distance Education' in the 1990s, is now an institution for bush children across the country.

The Rev Fred McKay who succeeded John Flynn as Superintendent of the Australian Inland Mission said of Traeger: "He created a social revolution. Human relations were transformed. In a very real way he made Outback Australia."

The Traeger pedal-radios continued to be used overseas. As recently as 1962, the Traeger Radio Company exported pedal sets to Nigeria. In 1970 the Canadian School of the Air and 20 developing countries relied on the Traeger pedal-radio for communications in remote areas.

Pedal-power is having a resurgence today and is the subject of research in institutions around the world. The Technical University of Madrid recently won an award for developing a pedal system enabling students to power their laptop while using them. Students at the Massachusetts Institute of Technology (MIT) designed a similar pedal-power generator to support the campus energy-saving goals as part of their IT Energy@MIT Initiative.

About Alfred Traeger (1895-1980)

Alfred Traeger was born in Victoria in 1895, the eldest son of Johann Hermann Traeger, farmer, and his wife Louisa, née Zerna. From a very early age Traeger was interested in electronics. In 1907, aged 12, Alfred made a telephone receiver from basic objects found around the house: he used fencing wire, pitch fork prongs as magnets, tobacco tin lids for the diaphragms, and charcoal from the kitchen stove to provide carbon granules for the microphone. He transmitted messages between the toolshed and his house 50 yards away.

From 1912 he studied mechanical and electrical engineering at the South Australian School of Mines and Industries and in 1915obtained an associate Diploma. He soon worked as an electrical engineer and, intrigued by radio, obtained an amateur operator's licence. He later set up his own electrical business and formed the Traeger Transceivers Pty Ltd.

From 1926 Traeger started working on radio experiments for Reverent John Flynn, at £500 a year. In 1928, Traeger invented the pedal-powered radio system which could receive and transmit messages across a distance of 1,500 km. He continued innovating and bringing new radio technology to the bush until his death in 1980.

Rita Orsini

Fred McKay, Traeger - The Pedal Radio Man, Boolarong Press, 1995
Richard Begbie, The Pedal Radio of the Great Outback, Antique Radio Classified, Vol 16, July 1999, Number 7
Rodney Champness, Outback communications: the Flying Doctor radios, Silicon Chip magazine, January 2005
David SS. 'Mantle of safety'-aero-medical service in Central Australia. J Postgrad Med 2000; 46:245
Ernestine Hill, Flying Doctor Calling, Angus and Robertson, 1948
Traeger, Alfred Hermann, Australian Dictionary of Biography online edition
The Royal Flying Doctor Service of Australia website www.flyingdoctor.net
Big Sky Stories, Radio National Hindsight, The Australian Landscape, A Cultural History (Sunday 11/11/2007) with Rev. Fred McKay of AIM
Royal Flying Doctor Service - www.powerhousemuseum.com/australia_innovates
School of the Air - www.powerhousemuseum.com/australia_innovates
Remote Learning - www.cultureandrecreation.gov.au/articles/schoolofair
Pedal Power at Universidad Politecnica de Madrid - www.upm.es
Pedal power at MIT - www.huliq.com/41308/students-get-charge-out-of-pedal-power


Object No.


Object Statement

Pedal generator, brass / steel / paint, designed by Alfred Traeger, unknown maker, used by the Flying Doctor Service, Cloncurry area, Australia c 1930 - 1940

Physical Description

Pedal Generator set designed to run the pedal wireless as used by the Flying Doctor Service. Made in Australia, c 1930-1940. The object consists of a coil generator, the rotor of which is turned by pedals on a horizontal shaft through a gearbox.


Stamped into top plate "198" / - + [negative & positive]



  • c 1930-1940


This generator was designed by Alfred Traeger and made in Australia by an unknown maker.



This pedal generator was used in the Cloncurry area of Queensland


Credit Line

Gift of Mr H D MacAndrew, 1974

Acquisition Date

20 February 1974

Cite this Object


Traeger Pedal generator used by the Flying Doctor Service 2020, Museum of Applied Arts & Sciences, accessed 2 March 2021, <https://ma.as/210776>


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