See below 1.           St. Gerard's Primary School hall as it stands today.

1. 'The Coastal Radio Transmitting station at Pennant Hills, 1930' (courtesy Len Cookson) (This area is now called Carlingford) In the foreground is North Rocks Road. Towards the top of the photograph, you can see Pennant Hills Road. In this photograph the building marked as A. is the present day St Gerard's School Hall, B. is the only one remaining concrete anchor block, that were built to hold the wire cables that held up the Radio aerial tower; and C. highlights two other wire anchor cables that you can see in the photograph.

A) 1895: MARCONI'S INVENTION

            

        Scientists and other experts held that electromagnetic waves could only be transmitted in a straight line and then only if there was nothing in the way. Above all, they thought that the main obstacle was the curvature of the earth's surface. Marconi, (like every self-taught man) was more interested in practice than theory, and so he placed his transmitter near his house and the receiver three kilometres away, behind a hill. Overseeing it, there was the Marconi's servant, Mignani, whose only duty consisted in firing a rifle shot when the signal was received.

When Mignani fired his gun, for the first time in history the three dots of the letter "S" of the Morse alphabet had travelled through space. Marconi found little enthusiasm for his invention in Italy: the appropriate Italian minister even considered that it was "not suitable for telecommunications"!
                                                                    
First Marconi's radiotrasmitter used in Villa Grifone, Bologna

patent his invention. In 1897, the British Ministry of Posts gave him money and technicians to continue his experiments and transmission distances became longer and longer: five, eight, fifteen, 30 and 100 kilometres. Radiotelegraphy had become a reality. [Radio-telegraphy is the sending by radio waves the same dot-dash message (morse code) used in a telegraph. ]

         
                                                                   

B) The Role of [Australian] Coastal Radio Stations in the Early Days of Communications With Aircraft
                                               by Roger Meyer

The Coastal Radio Service, established for communications with ships, had nothing to do with aviation… Or did it? Please read on.

The Wireless Telegraphy Act 1905 gave control of all wireless communications to the Commonwealth Government. In 1909 the House of Representatives resolved that wireless telegraphic stations should be established around the coasts of Australia, and that merchant ships should be equipped with wireless installations to:
a) gain intelligence of the appearance in Australian waters of hostile forces, and
b) assist in saving life and property imperilled by accidents upon the sea.

The Australasian Wireless Co. of Sydney won the tender to install, on behalf of the Postmaster General, wireless stations at Perth and Sydney.

This company virtually established Australia’s radio industry by taking the initiative of installing radio equipment in merchant ships and operating experimental shore stations. In 1910 they were granted a licence to operate a wireless station and conduct telegraphy tests with ships at sea. Their station was located in the Hotel Australia, Sydney. The aerial mast was attached to the hotel’s chimney. Thus in 1911 the first coastal radio station was established. The transmitter had a range of 520 kilometres.

The permanent network of stations initially involved the two high powered (25 kW) stations at Sydney [Carlingford*] and Perth (Applecross), and a network of 17 low powered stations. These were installed between 1912 and 1914. [*The site of present day St Gerard's Primary School and Carlingford High School]

below right: Made by AWA, the VK2ME transmitter rated 20kW and broadcast on 9590kc

You can see St Gerard's hall in the above photograph.

A consequence of the loss of the British liner Titanic was the Navigation Act 1912 which required any ship carrying more than 50 persons in Australian waters to fitted with wireless communications apparatus. It also required a suitably qualified operator to work the equipment.

At that time, the Marconi and Telefunken companies were in strong competition for the world telecommunications market. Marconi sued the Australasian Wireless Company for infringement of its patents. The dispute was settled when, in 1912, the companies agreed to exchange patents, and the Australian Wireless Co. merged with the Australian branch of Marconi to form Amalgamated Wireless (Australasia) Ltd. (AWA).

The aim of the original network was to ensure that all ships in Australian waters would be in contact with at least one station at all times. The range of the transmitters was soon increased to 700 km by day and up to 3,500 km at night. The operating frequency was 500 kHz.

In 1922 AWA was granted exclusive rights to operate an expanded network of 27 stations which comprised the Coastal Radio Service (CRS), which they continued to do for the next 25 years. These included stations in New Guinea, which had been hurriedly installed when Japan entered Word War II. The Overseas Telecommunications Act 1946 resulted in the creation of the Overseas Telecommunications Commission and ownership of the CRS was transferred to this new rganization on 1 October 1946.

The first passenger aircraft to be fitted with wireless communications was the Tasmanian Aerial Services DH84 Dragon VH-URD Miss Launceston, in 1934. By the end of 1937, about 24 Australian aircraft had been fitted with radio equipment. Prior to the creation of the Aeradio service in 1938-39, the Civil Aviation Board arranged for AWA to provide an interim ground-to-air communications service. This was achieved through a combination of Coastal Radio Stations and temporary stations at aerodromes. Frequencies of 333 kHz and 325 kHz were allocated for the service. The Coastal Radio Stations provided a ready-made network for communication with aircraft in flight.  

The first flight across the Pacific in 1928 was by Charles Kingsford Smith, Charles Ulm, Harry Lyon and wireless operator Jim Warner. It was the first overseas flight to be equipped with radio communications equipment. Sydney Radio [Carlingford*] kept contact throughout the flight. [*The site of present day St Gerard's Primary School and Carlingford High School]

The mobile communications and direction finding facility which had been used at Charleville during the 1934 Centenary air race from England to Australia was later moved to Western Junction (Launceston) to aid aircraft crossing Bass Strait from the mainland.

A temporary station was also established at Darwin airport for the 1934 air race, and this continued to operate until 1940. Darwin also provided radio communications with aircraft on the Australia to England airmail service. Communications could be maintained as far as Kupang in Timor…..

Acknowledgment: The source of this article is The Seawatchers by Lawrence Durrant (Angus and Robertson Publishers, 1986).

From: http://www.airwaysmuseum.com/Coastal%20Radio%20Stations.htm

This document is about a request made by a Western Australian politician that 3 old buildings belonging to a Western Australian Wireless site, not be pulled down.

The Western Australian wireless station and tower were a sister site to the wireless station that was build at Carlingford. This document gives information about the sort of work the wire stations did.

c) Legislative Council of Western Australia Hansard for 10/12/2003
                                                        
                                                         Legislative Council

Wednesday, 10 December 2003

WIRELESS HILL PARK, ARDROSS - SUBMISSION NO 17 - EXCISION FROM A-CLASS RESERVE 29813

Motion for Disallowance
HON BARBARA SCOTT (South Metropolitan) [4.27 pm]: I move -

That submission No 17 of 2003 - excision [removal], from class A reserve 29813 [status], Wireless Hill Park, Ardross - tabled in the Legislative Council on 11 September 2003 under section 42(4)(a) of the Land Administration Act 1997, be and is hereby disallowed.

I would like to mount a case to the Parliament this afternoon that the importance of preserving the history and heritage of this significant site and the integrity of the whole site is of much pre-eminence to people who live in the region and others in Western Australia, and Australia-wide, in fact. It is the uniqueness of the site that has caused so much interest in this motion…….

Briefly, the history is that in September 1911 the land for the wireless station site was purchased by the federal Government, and construction of the wireless station commenced.

Once commissioned, the facility provided important all-weather radio communications with the outside world. The wireless station was the Western Australian component of a network of five main radio communication stations across Australia that participated in international, national, state-wide and regional radio communications and broadcasting. It is important to note that of the original wireless stations across Australia, only the Applecross wireless station still remains in its original form.

The station was used continuously between 1912 and 1967 by the postmaster general’s department as the main coastal radio communication centre for the State. In 1926 it became a feeder station for international radiograms and from 1943 it was used as an alternative station for international short-wave radio messages. It also played a significant part in the First World War and the Second World War, providing vital military communications.

As I said, I want to refer to a number of letters and information that I have been given but time does not allow me to do all of that. However, it is significant that I should quote from a letter that was sent to me from Mr Bruce James, the immediate past president of the Engineering Heritage Panel of the Western Australian division of Engineers Australia.

In his letter he has raised a number of concerns about the proposal to excise those four heritage-listed houses [built originally for housing the wireless station staff] from the Wireless Hill site. His first concern is the history, which I have briefly outlined. In his letter he has written about Marconi in detail and states –

“….In 1894, Marconi began experimenting at his father’s estate in Pontecchio, near Bologna, using comparatively crude apparatus; an induction coil with a spark discharger controlled by a Morse tapping key at the sending end and a simple filings coherer at the receiver.

As he received little encouragement to continue his experiments in Italy, he was advised . . . to go to England; and in February 1896 he arrived in London and met William Preece, Engineer-in-Chief of the Post Office, who offered him every assistance and encouragement.

In 1912 he introduced the time-spark system of generating pseudocontinuous waves in place of the damped trains of waves produced by the older spark transmitters. This effected a considerable improvement in the selectivity of transmission and reception with a further gain in efficiency. This system was used for several years at many important long distance stations; and by its means Marconi sent the first message ever transmitted by wireless from England to Australia, in September 1918.

That emphasises the uniqueness of the Wireless Hill site and its relevance and connection to Marconi, who invented the radio, and to the first radio contact across Australia. Mr Bruce James sets out in great detail the history of radio stations in Australia when tenders were called for two special transmitters - one in Sydney and one in Perth - that would enable radio messages to be sent directly across the continent for the first time. The letter further states -

“Pennant Hills in North Sydney [the area rezoned as Carlingford, and now the site of St. Gerard's Primary and  School Carlingford High School ] and Applecross in Perth were the two selected sites and came into operation in 1912, just 18 years after Marconi started his first experiment in Italy.”

He also enabled the first radio contact to be made with Indian Ocean shipping. The letter further states -
“The opening of the Perth Wireless Station also enabled direct contact to be made with a large amount of shipping in the Indian Ocean for the first time, covering maritime safety and weather forecasting among its many uses.

Its position during World War I also makes it quite important and unique.

Bruce James continues -
During World War One, this Wireless Station was taken over by the Navy and used in a very important aspect for the defense of the western part of the continent. After peace was declared, the site was transferred back to its original civilian use.

It was also used during World War II and used again by the Navy on military defense matters. The important thing about the uniqueness of Wireless Hill is that Pennant Hills wireless station in Sydney has now gone. In the 1960s there was a change of requirement for this type of radio transmission in Sydney and the Pennant Hills site was closed down. The complete land area was sold for urban development. Nothing remains today to indicate the very important role it played over such a long period starting some nine decades ago.

He concluded -
PLEASE SUPPORT NOT ONLY WE ENGINEERS, BUT ALSO THE FUTURE GENERATIONS OF AUSTRALIANS WHO WILL VALUE THEIR COMMUNICATIONS MUSEUM IN ITS WONDERFUL PARKLAND SETTING, BY OPPOSING ANY PROPOSAL TO EXCISE THESE FOUR RESIDENCES AND THEIR SERVICE ROAD FROM THE OVERALL WIRELESS HILL PARK.

___________________________________________________________________________________________

  1930's art deco style logo for VK2ME, Sydney (Carlingford)

This web page has information on later radio stations that were also broadcast from the wireless station at Carlingford.

__________________________________________________________________________________

More details about how radios work:

Radio owes its development to two other inventions, the telegraph and the telephone, all three technologies are closely related. Radio technology began as "wireless telegraphy".

Radio can refer to either the electronic appliance that we listen with or the content listened to. However, it all started with the discovery of "radio waves" - electromagnetic waves that have the capacity to transmit music, speech, pictures and other data invisibly through the air. Many devices work by using electromagnetic waves including: radio, microwaves, cordless phones, remote controlled toys, television broadcasts, and more.

The Roots of Radio

During the 1860s, Scottish physicist, James Clerk Maxwell predicted the existence of radio waves; and in 1886, German physicist, Heinrich Rudolph Hertz demonstrated that rapid variations of electric current could be projected into space in the form of radio waves similar to those of light and heat.

In 1866, Mahlon Loomis, an American dentist, successfully demonstrated "wireless telegraphy." Loomis was able to make a meter connected to one kite cause another one to move, marking the first known instance of wireless aerial communication.

Guglielmo Marconi

Guglielmo Marconi, an Italian inventor, proved the feasibility of radio communication. He sent and received his first radio signal in Italy in 1895. By 1899 he flashed the first wireless signal across the English Channel and two years later received the letter "S", telegraphed from England to Newfoundland. This was the first successful transatlantic radiotelegraph message in 1902.

Nikola Tesla

In addition to Marconi, two of his contemporaries Nikola Tesla and Nathan Stufflefield took out patents for wireless radio transmitters. Nikola Tesla is now credited with being the first person to patent radio technology; the Supreme Court overturned Marconi's patent in 1943 in favor of Tesla.

Growth of Radio - Radiotelegraph and Spark-Gap Transmitters

Radio-telegraphy is the sending by radio waves the same dot-dash message (morse code) used in a telegraph. Transmitters at that time were called spark-gap machines. It was developed mainly for ship-to-shore and ship-to-ship communication. This was a way of communicating between two points, however, it was not public radio broadcasting as we know it today.

Wireless signals proved effective in communication for rescue work when a sea disaster occurred. A number of ocean liners installed wireless equipment. In 1899 the United States Army established wireless communications with a lightship off Fire Island, New York. Two years later the Navy adopted a wireless system. Up to then, the Navy had been using visual signaling and homing pigeons for communication.

In 1901, radiotelegraph service was instituted between five Hawaiian Islands. By 1903, a Marconi station located in Wellfleet, Massachusetts, carried an exchange or greetings between President Theodore Roosevelt and King Edward VII. In 1905 the naval battle of Port Arthur in the Russo-Japanese war was reported by wireless, and in 1906 the U.S. Weather Bureau experimented with radiotelegraphy to speed notice of weather conditions.

In 1909, Robert E. Peary, arctic explorer, radiotelegraphed: "I found the Pole". In 1910 Marconi opened regular American-European radiotelegraph service, which several months later, enabled an escaped British murderer to be apprehended on the high seas. In 1912, the first transpacific radiotelegraph service linked San Francisco with Hawaii.

Improvements to Radio Transmitters

Overseas radiotelegraph service developed slowly, primarily because the initial radiotelegraph transmitter discharged electricity within the circuit and between the electrodes was unstable causing a high amount of interference. The Alexanderson high-frequency alternator and the De Forest tube resolved many of these early technical problems.

Lee DeForest - AM Radio

Lee Deforest invented space telegraphy, the triode amplifier and the Audion. In the early 1900s, the great requirement for further development of radio was an efficient and delicate detector of electromagnetic radiation. Lee De Forest provided that detector. It made it possible to amplify the radio frequency signal picked up by the antenna before application to the receiver detector; thus, much weaker signals could be utilized than had previously been possible. De Forest was also the person who first used the word "radio".

The result of Lee DeForest's work was the invention of amplitude-modulated or AM radio that allowed for a multitude of radio stations. The earlier spark-gap transmitters did not allow for this.

http://inventors.about.com/od/rstartinventions/a/radio.htm

         Guglielmo Marconi (1874-1937)

On a German stamp celebrating one hundred years of radio transmission. 

Early in the 19th century, Michael Faraday, an English physicist, demonstrated that an electrical current could produce a magnetic field.

In 1864, James Clerk Maxwell, a professor of experimental physics at Cambridge, proved mathematically that any electrical disturbance, that generates an electromagnetic field, could produce an effect at a considerable distance from the point at which it occurred and predicted that electromagnetic energy could travel outward from a source as waves moving at the speed of light.

In 1888 Heinrich Hertz demonstrated that Maxwell’s prediction was true for transmission over a short distance.

In 1901 the Italian physicist, Guglielmo Marconi, perfected a radio system that transmitted Morse code over the Atlantic Ocean.

In 1906 the American physicist Lee De Forest invented the vacuum tube which amplified radio signals that were received by antenna, thus much weaker signal could be transmitted over longer distance. The vacuum tube was also used to generate radio waves and soon become the main component of radio transmitter.



After World War II more advancements were made: The replacement of the vacuum tube by the transistor and of wires by printed circuits drastically reduced the power that radio equipment needed to operate enabling radio components miniaturization and more reliability.

During the years claims were made that as a matter of fact not Marconi invented radio but Oliver Lodge, Alexander (Aleksandr) Popov or Nikola Tesla , had sent wireless messages before Marconi got his patent.

It does not really matter. What Marconi undoubtedly did invent was an entirely new science-based

industry. In his hands an obscure and, to most people, unintelligible branch of physics became a consumer product like no other. We are used to being told that some new technology will change the world. Marconi's is one of the few that did.

For his scientific contribution Marconi was awarded the Nobel Prize in physics for the year 1909.

                  
Repeat Marconi's Radio Experiments

A schematic of Marconi's 1900 wireless system

As a rule: experiments with electricity should be performed under the supervision of teachers or adults familiar with electricity safety procedures. Especially, take in account that experiments with induction coils and capacitors can produce high voltage shocks.

Marconi's experiment – creating, sending and detecting radio waves – is relatively simple, not beyond the abilities of middle school students. In order to begin, read carefully the resources provided by the following site and ensure that you understand the basic principals. Brows further the web and consult your local library, your teacher and other knowledgeable adults and experts.  http://www.juliantrubin.com/bigten/marconiradioexperiments.html

From Pioneer’s Track – Beecroft Epping Hornsby A Hornsby Shire Council Project Ray Park Heritage Group Incorporated

From: www.interactive-learning.com.au  Please report any expired links