THE HISTORY OF SHORTWAVE RADIO IN AUSTRALIA

1906 - Wireless Telephony

Home
Project Overview
1800s - Land Telegraphy
1874 - Guglielmo Marconi - a Tribute
1895 - Wireless Telegraphy
1901 - Wireless Telegraphy
1902 - Wireless Telegraphy in Australia
1904 - Australian Coastal Radio
1906 - Wireless Telephony
1912 - Melbourne Radio - VIM
1914 - Shortwave Wireless Telephony
1920s - Commercial Shortwave Telephony Development
1920s - Receivers
1920 - The huge RCA Longwave Station in New York
1920 - Wireless broadcasting in Australia
1920s - First shortwave stations in Victoria
1921 - Discovery of Shortwave Propagation
1921 - Koo Wee Rup (Victoria) Experimental Wireless Receiving Station
1923- Longwave Broadcasting in Australia
1923 - Evolution of Australian Domestic Radio
1924 - 3LO - Melbourne's Second Broadcaster
1924 - 3AR - Melbourne's first broadcaster
1924 - The Braybrook (Melbourne) Transmitting Site
1925 - First Shortwave Stations in Western Australia
1926 - First Shortwave Stations in New South Wales
1926 - RAAF Communications - Laverton (Vic)
1927 - Beam Wireless Worldwide
1927 - Beam Wireless from Australia
1928 - ABC Lyndhurst (Victoria)
1930 - AWA Receiving Station at La Perouse (Sydney)
1930 - AWA Radio Centre at Pennant Hills
1933 (to 1969) - Shortwave Radio Clubs in Australia
1936 - Ship Broadcaster - the MS Kanimbla
1939 - Belconnen Communications Station (Canberra)
1940 - RAAF Receiving Station at Werribee (Victoria)
1941 - RAAF Frognall (Melbourne)
1941 - ABC Brisbane
1942 - Army Wireless Chain - west of Melbourne
1942 - Dutch Stations in Australia
1943 - ABC Radio Australia - Shepparton (Victoria)
1943 - Army Shortwave HF Stations in Melbourne
1944 - ABC - Radio Australia - Looking Back
1945 - PMG Receiving Station - Highpark (Victoria)
1945 - Radio Australia - DXers Calling
1946 - Radio Australia - Communications Programs
1946 - VNG Time Signal Station
1948 - Radio Australia QSL Cards
1948 - ABC Sydney
1966 - ABC Cox Peninsula (Darwin)
1970 (to 2012) - Shortwave Radio Clubs in Australia
1975 - ABC Gnangara (Western Australia)
1975 - ABC Carnarvon (Western Australia)
1978 - Omega Navigation Station - Woodside (Victoria)
1985 - ABC Northern Territory
1989 - ABC Brandon (Queensland)
2003 - Private Shortwave Broadcasters
Timeline - Part One - 1839 to 1927
Timeline - Part Two - 1928 to 2012
SPECIAL - Licencing of Shortwave Broadcasters
SPECIAL - Radio Receivers for Shortwave
SPECIAL - Radio Monitoring as a Hobby
Epilogue
Bibliography, References and Resources
Links to the author's personal websites

1906fessendenlabbrantrock.jpg
1906 - Fessenden laboratory at Brant Rock

THE VACUUM TUBE (VALVE)
The years leading up to 1920s saw various advancements and developments in spark gap transmitter technology, extending into the early 1920s, but the invention of the “valve” would revolutionise long distance wireless communication and which would cause the advancement of the network of spark gap transmitters which had been constructed around the world.

Whilst spark transmitters were reasonably successful in spanning long distances for telegraphy, attempts to transmit speech, music were ill-fated, due to the unsuitability of spark technology as the medium. Stability of the wave train was inadequate, and the irregular nature of the transmission virtually prevented any real advancement in transmission of speech or music over long distances

 

The invention of the “valve” heralded a new era in wireless communications. It is outside this scope of this project to consider, in detail, the events, achievements and discoveries surrounding the invention of the valve, but we should at least consider that Fleming was associated with the earliest experiments as far back as 1887, in his research into the effects observed by Thomas Edison in 1883 concerning incandescent electric lamps.

 

These studies resulted in the development of a "Fleming" valve, in 1904. Essentially it was a two element device known as a “diode”. In such a form, however, the diode was unsuitable for purposes other than power rectification and similar uses.

 

The experiments of Dr Lee de Forest, of New York, by the addition of a third element, or “grid”, created the "triode”, and with it, amplification, oscillation, and detection.

 

1900s to 1920s - WIRELESS TELEPHONY
Much progress had been accomplished in the period 1900-1920 for refinement in development of techniques used for radio telegraphy over long distances.

These early experiments were associated with rather crude forms of spark transmitters, which could give at best only a regular succession of shot trains of waves – one train for each spark that was passed.

However, the transmission of speech and music by radio had seen only limited success, with the early experimenters using Alexanderson alternators for generating the RF signal, modulated by telephone-type microphones.

What is recognized historically as the first recorded event of a wireless broadcast occurred in 1906, from an experimental station at Brant Rock, Massachusetts, USA, organized by Reginald A. Fessenden.

The station was established in 1905. A 180 metre high tubular antenna with an insulated base was setup and held in place with guy wires that used the same technology that Roebling developed for the Brooklyn Bridge.

From Brant Rock on Christmas Eve in 1906 Fessenden became the first person to broadcast musical and vocal programs over the air. The broadcast was heard by US Navy and United Fruit Company wireless operators in ships along the east coast since the receivers were equipped with appropriate rectifiers.

Following initial tests with voice transmissions over about 2 km, using a spark transmitter and conventional telephone, Fessenden in 1905 built a 10 kHz alternator, which proved the practicability of “wireless” transmission of voice in a laboratory setting. In 1906, a 50 KHz alternator was used, with 1 kW output, resulting in successful experimental transmission of music and speech over about 15 km.

The Website of the New England Wireless and Steam Museum, Inc . at Brant Rock has many historical and  contemporary images of the station.

New England Wireless and Steam Museum

 

1906brantrockmasts.jpg
Brant Rock station (colorized) 1906

brantrocktxer1906.jpg
1906 - Brant Rock transmitter

1906brantrockieeeplaque.jpg
Commemorative Plaque at Brant Rock

varberglwstation.jpg
Varberg (Sweden) - original longwave station, operates once a year for special events

varbergtxer.jpg
Varberg (Sweden) longwave transmitter in 2011

Wireless Telephony Advancements on Longwave
The years 1908-1915 saw moderate progress made in the use of the triode valve for radio telephony transmissions. Some of the more important long-distance events are as follows, which were radiated on what would become the longwave band.

1908 - de Forest succeeded with test transmissions from the Eiffel Tower, Paris, heard up to 800 km away

1910 - de Forest sent a program from the Metropolitan Opera building, using 500 kW

1914 - a Belgian station came on the air at Larken

1915 - in Arlington, NY, the US Navy station sent speech and music to Paris and elsewhere.

The period 1914-1919 during WW1 was a time when private radio experimentation ceased or was banned in many countries. Nevertheless, the war effort saw rapid development of radio communications for military purposes.

By 1919, radio experimentation by returned servicemen started to boom. In Australia and England, special permission had to be obtained from the Governments before private experiments could take place, either for radio telegraphy or radio telephony.

An important event in 1919 was the granting of a license by the British Government to the Marconi Wireless Telegraph Company, resulting in the opening of a 6 kW longwave telephony transmitter at Chelmsford, Essex. Many demonstration broadcasts were transmitted, and heard in various countries, on a longwave frequency of about 120 kHz, with the callsign 2MT.

Many demonstration broadcasts were given, including one in which the voice of Dame Nellie Melba was featured.

Some of those were received as far away as Iran, Madrid, and various other European countries.

rugby1927lwtransmitter.jpg
1927 - Rugby (UK) longwave telephony transmitters

In 1920, the world's first wireless telephone news service commenced from the Chelmsford station, and the public interest was stimulated in the same year by special transmissions to Australia. Regular broadcasts from Chelmsford started in 1921.


1920 was the year in which serious research into wireless telephony, with innumerable tests and experiments, commenced - one such achievement was the relay of concert programs of distances up to 1600 km to the SS Victoria.

In Australia, as well as in many other countries, radio telephone links were being set up on a worldwide basis - circuits were established to such countries as UK, NZ, Canada and USA, following the changeover from spark to valve operated equipment.

As early as 1921, American amateur radio operators spoke over long distances on about 1500 kHz, in spectrum which would become the medium wave band.

In 1922, Marconi opened the famous London station 2LO, and in the same year the BBC was formed, initially using the Marconi transmitter 2LO for the first broadcasts in the mediumwave band.

Elsewhere in Europe, on both longwave and mediumwave, broadcasts commenced from the Eiffel Tower.

In 1922, longwave stations opened in Lusanne (Switzerland) and Moscow.

Other notable stations opened on longwave included:

1918 XWA Canada

1919 9XM University of Wisconsin, Canada

1919 PCGG Holland

1920 Buenos Aires, Argentina

1920 8MK Detroit

1920 KDKA Pittsburgh, Pa

1922 WBZ Springfield, Mass

Even though mediumwave development had begun, the installation of commercial longwave stations continued well into the 1930s. From about 1918 until the mid-1930s there were well over 100 longwave stations in operation, and new longwave stations were set up in Argentina, USA, Turkey, Iceland, India, Afghanistan and Hong Kong.

But this form of transmission of radio telephony was extremely limited and no further progress occurred, considering the serious practical difficulties involved. The medium just wasn't adequate for telephony transmissions and another form of technology was necessary.


Enter supporting content here

Contact the author at this Email link