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129-752: Bald Hills Radiator is a radio transmission centre at 99 Kluver St, Bald Hills , City of Brisbane , Queensland, Australia. It is also known as the National Broadcasting Service Radio Transmission Centre . It is listed on the Brisbane Heritage Register . The centre transmits all the Brisbane AM radio programmes of the Australian Broadcasting Corporation (ABC) . The site and infrastructure

258-471: A directional antenna transmits radio waves in a beam in a particular direction, or receives waves from only one direction. Radio waves travel at the speed of light in vacuum and at slightly lower velocity in air. The other types of electromagnetic waves besides radio waves, infrared , visible light , ultraviolet , X-rays and gamma rays , can also carry information and be used for communication. The wide use of radio waves for telecommunication

387-418: A microphone , a video signal representing moving images from a video camera , or a digital signal consisting of a sequence of bits representing binary data from a computer. The modulation signal is applied to a radio transmitter . In the transmitter, an electronic oscillator generates an alternating current oscillating at a radio frequency , called the carrier wave because it serves to generate

516-497: A radar screen . Doppler radar can measure a moving object's velocity, by measuring the change in frequency of the return radio waves due to the Doppler effect . Radar sets mainly use high frequencies in the microwave bands, because these frequencies create strong reflections from objects the size of vehicles and can be focused into narrow beams with compact antennas. Parabolic (dish) antennas are widely used. In most radars

645-474: A " push to talk " button on their radio which switches off the receiver and switches on the transmitter. Or the radio link may be full duplex , a bidirectional link using two radio channels so both people can talk at the same time, as in a cell phone. One way, unidirectional radio transmission is called simplex . This is radio communication between a spacecraft and an Earth-based ground station, or another spacecraft. Communication with spacecraft involves

774-627: A Service Regulation specifying that "Radiotelegrams shall show in the preamble that the service is 'Radio ' ". The switch to radio in place of wireless took place slowly and unevenly in the English-speaking world. Lee de Forest helped popularize the new word in the United States—in early 1907, he founded the DeForest Radio Telephone Company, and his letter in the 22 June 1907 Electrical World about

903-412: A controller device control the actions of a remote device. The existence of radio waves was first proven by German physicist Heinrich Hertz on 11 November 1886. In the mid-1890s, building on techniques physicists were using to study electromagnetic waves, Italian physicist Guglielmo Marconi developed the first apparatus for long-distance radio communication, sending a wireless Morse Code message to

1032-421: A given bandwidth than analog modulation , by using data compression algorithms, which reduce redundancy in the data to be sent, and more efficient modulation. Other reasons for the transition is that digital modulation has greater noise immunity than analog, digital signal processing chips have more power and flexibility than analog circuits, and a wide variety of types of information can be transmitted using

1161-548: A government license, such as the general radiotelephone operator license in the US, obtained by taking a test demonstrating adequate technical and legal knowledge of safe radio operation. Exceptions to the above rules allow the unlicensed operation by the public of low power short-range transmitters in consumer products such as cell phones, cordless phones , wireless devices , walkie-talkies , citizens band radios , wireless microphones , garage door openers , and baby monitors . In

1290-632: A lake 60 kilometres (37 mi) long. The barrage was funded by the Rockhampton City Council to provide a reliable source of water to the city, and to effectively drought proof Rockhampton. In 2002, a study showed that salinity was increasing in the Fitzroy Basin and, while only small areas of land were severely affected by salinity, urged that steps be taken to manage salinity by good irrigation practices and better management of tree clearing. In 1989, two bombs exploded inside

1419-587: A large economic cost, but it can also be life-threatening (for example, in the case of interference with emergency communications or air traffic control ). To prevent interference between different users, the emission of radio waves is strictly regulated by national laws, coordinated by an international body, the International Telecommunication Union (ITU), which allocates bands in the radio spectrum for different uses. Radio transmitters must be licensed by governments, under

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1548-595: A metal conductor called an antenna . As they travel farther from the transmitting antenna, radio waves spread out so their signal strength ( intensity in watts per square meter) decreases (see Inverse-square law ), so radio transmissions can only be received within a limited range of the transmitter, the distance depending on the transmitter power, the antenna radiation pattern , receiver sensitivity, background noise level, and presence of obstructions between transmitter and receiver . An omnidirectional antenna transmits or receives radio waves in all directions, while

1677-427: A more limited information-carrying capacity and so work best with audio signals (speech and music), and the sound quality can be degraded by radio noise from natural and artificial sources. The shortwave bands have a greater potential range but are more subject to interference by distant stations and varying atmospheric conditions that affect reception. In the very high frequency band, greater than 30 megahertz,

1806-470: A primitive spark-gap transmitter . Experiments by Hertz and physicists Jagadish Chandra Bose , Oliver Lodge , Lord Rayleigh , and Augusto Righi , among others, showed that radio waves like light demonstrated reflection, refraction , diffraction , polarization , standing waves , and traveled at the same speed as light, confirming that both light and radio waves were electromagnetic waves, differing only in frequency. In 1895, Guglielmo Marconi developed

1935-420: A public audience. Analog audio is the earliest form of radio broadcast. AM broadcasting began around 1920. FM broadcasting was introduced in the late 1930s with improved fidelity . A broadcast radio receiver is called a radio . Most radios can receive both AM and FM. Television broadcasting is the transmission of moving images by radio, which consist of sequences of still images, which are displayed on

2064-459: A radio signal is usually concentrated in narrow frequency bands called sidebands ( SB ) just above and below the carrier frequency. The width in hertz of the frequency range that the radio signal occupies, the highest frequency minus the lowest frequency, is called its bandwidth ( BW ). For any given signal-to-noise ratio , an amount of bandwidth can carry the same amount of information ( data rate in bits per second) regardless of where in

2193-489: A receiver that is typically colocated with the transmitter. In radio navigation systems such as GPS and VOR , a mobile navigation instrument receives radio signals from multiple navigational radio beacons whose position is known, and by precisely measuring the arrival time of the radio waves the receiver can calculate its position on Earth. In wireless radio remote control devices like drones , garage door openers , and keyless entry systems , radio signals transmitted from

2322-533: A recipient over a kilometer away in 1895, and the first transatlantic signal on 12 December 1901. The first commercial radio broadcast was transmitted on 2 November 1920, when the live returns of the Harding-Cox presidential election were broadcast by Westinghouse Electric and Manufacturing Company in Pittsburgh, under the call sign KDKA . The emission of radio waves is regulated by law, coordinated by

2451-673: A reference to the radiotelegraph and radiotelegraphy . The use of radio as a standalone word dates back to at least 30 December 1904, when instructions issued by the British Post Office for transmitting telegrams specified that "The word 'Radio'... is sent in the Service Instructions." This practice was universally adopted, and the word "radio" introduced internationally, by the 1906 Berlin Radiotelegraphic Convention, which included

2580-663: A referendum. Before the 2008 amalgamation, the City of Rockhampton had a population of approximately 74,530, Fitzroy Shire approximately 11,357, and Mount Morgan Shire approximately 2,925 people. Proposed boundary changes between Rockhampton Regional Council and Livingstone Shire Council are under review by the Local Government Change Commission. The changes relate to three suburbs contiguous with Rockhampton City which are presently part of Livingstone Shire. The proposed changes will affect 1170 properties in

2709-446: A screen on a television receiver (a "television" or TV) along with a synchronized audio (sound) channel. Television ( video ) signals occupy a wider bandwidth than broadcast radio ( audio ) signals. Analog television , the original television technology, required 6 MHz, so the television frequency bands are divided into 6 MHz channels, now called "RF channels". The current television standard, introduced beginning in 2006,

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2838-464: A secessionist movement with the intentions of breaking away from the state of Queensland. The core argument of movement was that the seat of government, Brisbane was in the south-east corner of the State. It was so far removed from substantial portions of the state that these areas and their citizens were left disadvantaged and neglected as political and economic interests focused on the south. Supplementing

2967-441: A smaller bandwidth than the old analog channels, saving scarce radio spectrum space. Therefore, each of the 6 MHz analog RF channels now carries up to 7 DTV channels – these are called "virtual channels". Digital television receivers have different behavior in the presence of poor reception or noise than analog television, called the " digital cliff " effect. Unlike analog television, in which increasingly poor reception causes

3096-416: A television (video) signal has a greater data rate than an audio signal . The radio spectrum , the total range of radio frequencies that can be used for communication in a given area, is a limited resource. Each radio transmission occupies a portion of the total bandwidth available. Radio bandwidth is regarded as an economic good which has a monetary cost and is in increasing demand. In some parts of

3225-400: A transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft and missiles, a beam of radio waves emitted by a radar transmitter reflects off the target object, and the reflected waves reveal the object's location to

3354-652: A transmitter to control the actions of a device at a remote location. Remote control systems may also include telemetry channels in the other direction, used to transmit real-time information on the state of the device back to the control station. Uncrewed spacecraft are an example of remote-controlled machines, controlled by commands transmitted by satellite ground stations . Most handheld remote controls used to control consumer electronics products like televisions or DVD players actually operate by infrared light rather than radio waves, so are not examples of radio remote control. A security concern with remote control systems

3483-475: A truly awesome appearance when in operation, supplemented by a sound effect as the cooling system pump and fan operated. In a paper presented to the Institution of Engineers, Australia shortly before his death, Sanderson wrote: "These early units with prolific meters and open mesh panels, behind which the large glass transmitting valves glowed cherry red, contrasting with the strange blue pulsating plasmas of

3612-435: A variety of license classes depending on use, and are restricted to certain frequencies and power levels. In some classes, such as radio and television broadcasting stations, the transmitter is given a unique identifier consisting of a string of letters and numbers called a call sign , which must be used in all transmissions. In order to adjust, maintain, or internally repair radiotelephone transmitters, individuals must hold

3741-499: A year, gold was found at Canoona , and led to the first North Australian gold rush. The Canoona gold rush led to an influx of migrants that transformed Rockhampton into the second-largest port in the state; during this period, Rockhampton became infamous for crime and violence, and was described by the then visiting English novelist, Anthony Trollope as the "City of the Three S's"—"sin, sweat, and sorrow". Subsequent gold discoveries at

3870-413: Is amplified in the transmitter and applied to a transmitting antenna which radiates the energy as radio waves. The radio waves carry the information to the receiver location. At the receiver, the radio wave induces a tiny oscillating voltage in the receiving antenna which is a weaker replica of the current in the transmitting antenna. This voltage is applied to the radio receiver , which amplifies

3999-703: Is spoofing , in which an unauthorized person transmits an imitation of the control signal to take control of the device. Examples of radio remote control: Radio jamming is the deliberate radiation of radio signals designed to interfere with the reception of other radio signals. Jamming devices are called "signal suppressors" or "interference generators" or just jammers. During wartime, militaries use jamming to interfere with enemies' tactical radio communication. Since radio waves can pass beyond national borders, some totalitarian countries which practice censorship use jamming to prevent their citizens from listening to broadcasts from radio stations in other countries. Jamming

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4128-657: Is a city in the Rockhampton Region of Central Queensland , Australia. In the 2021 census , the population of Rockhampton was 79,293. A common nickname for Rockhampton is 'Rocky', and the demonym of Rockhampton is Rockhamptonite. The Scottish- Norwegian explorers Charles and William Archer came across the Toonooba River in 1853 and named it in-honour of Sir Charles FitzRoy ; they also named many local landmarks after figures in Norse mythology , including

4257-445: Is a digital format called high-definition television (HDTV), which transmits pictures at higher resolution, typically 1080 pixels high by 1920 pixels wide, at a rate of 25 or 30 frames per second. Digital television (DTV) transmission systems, which replaced older analog television in a transition beginning in 2006, use image compression and high-efficiency digital modulation such as OFDM and 8VSB to transmit HDTV video within

4386-499: Is a triangular section lattice steel structure, 204m high and with 8 ft (2.44m) sides, guyed at four levels in three directions. The earth system consists of 120 copper wire buried radials, each 200m long. The mast was energised by separate six wire lines, each 460m long but these have been replaced with an underground low-loss coaxial cable . The antenna is a Dual-frequency Anti-fading design built to radiate two frequencies simultaneously(612 KHz & 792 kHz) and minimise

4515-433: Is an audio transceiver , a receiver and transmitter in the same device, used for bidirectional person-to-person voice communication with other users with similar radios. An older term for this mode of communication is radiotelephony . The radio link may be half-duplex , as in a walkie-talkie , using a single radio channel in which only one radio can transmit at a time, so different users take turns talking, pressing

4644-410: Is called "tuning". The oscillating radio signal from the desired station causes the tuned circuit to resonate , oscillate in sympathy, and it passes the signal on to the rest of the receiver. Radio signals at other frequencies are blocked by the tuned circuit and not passed on. A modulated radio wave, carrying an information signal, occupies a range of frequencies . The information ( modulation ) in

4773-427: Is called an uplink , while a link that transmits data from the spacecraft to the ground is called a downlink. Radar is a radiolocation method used to locate and track aircraft, spacecraft, missiles, ships, vehicles, and also to map weather patterns and terrain. A radar set consists of a transmitter and receiver. The transmitter emits a narrow beam of radio waves which is swept around the surrounding space. When

4902-593: Is exemplified by the Fitzroy River ; which has a lengthy, well documented history of flood records dating back to 1859. The highest recorded flood occurred in January 1918 and reached 10.11 m (33.2 ft). More recently, being affected by the 2010–2011 Queensland floods the Fitzroy River peaked at 9.2 metres on 5 January 2011. Rockhampton has a number of heritage-listed sites. For details see

5031-565: Is in radio clocks and watches, which include an automated receiver that periodically (usually weekly) receives and decodes the time signal and resets the watch's internal quartz clock to the correct time, thus allowing a small watch or desk clock to have the same accuracy as an atomic clock. Government time stations are declining in number because GPS satellites and the Internet Network Time Protocol (NTP) provide equally accurate time standards. A two-way radio

5160-417: Is mainly due to their desirable propagation properties stemming from their longer wavelength. In radio communication systems, information is carried across space using radio waves. At the sending end, the information to be sent is converted by some type of transducer to a time-varying electrical signal called the modulation signal. The modulation signal may be an audio signal representing sound from

5289-707: Is now owned by BAI Communications who are contracted to broadcast ABC radio and TV signals nationally. Initially, radio transmission was totally from within the Brisbane city centre . The first transmitter for radio station 4QG was located in an inner courtyard in the Executive Building in the Brisbane city centre. Operated by the Queensland Government , it started transmitting in 1925. A more powerful transmitter replaced it in 1926, on

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5418-417: Is of totally Australian design and has a very high content of Australian manufacture, only meters and valves being imported. Its operation was water cooled , a technological practice of the time and was in either full-time or reserve service for forty five years, from 1943 until 1988. It is completely preserved, housed in its original 1943 location. The transmitter is a very significant historical relic, as it

5547-562: Is one of Australia's most significant 19th century streetscapes and is listed on the National Trust ; the quarter comprises three city blocks along Quay street, from Fitzroy to Derby street, and is known for its neoclassical architecture , dining and nightlife . Some of the historical sites and landmarks of the city include; St Aubins , Kenmore House , the Alexandra Railway Bridge , St Joseph's Cathedral and

5676-536: Is probably the only surviving specimen of this very interesting short wave transmitter type. The design by STC dates from the late 1930s. It has been recommended that the equipment should be retained as a broadcasting heritage exhibit. The other transmitters on the site form, with STCA880A, Australia's largest collection under one roof of retired and operating radio transmitters. Dating from 1948 or possibly earlier, they are, except for one recovered from 4QN Clevedon in 1960, in their original locations. The significance of

5805-524: Is the one-way transmission of information from a transmitter to receivers belonging to a public audience. Since the radio waves become weaker with distance, a broadcasting station can only be received within a limited distance of its transmitter. Systems that broadcast from satellites can generally be received over an entire country or continent. Older terrestrial radio and television are paid for by commercial advertising or governments. In subscription systems like satellite television and satellite radio

5934-571: Is the only Australian university with a campus presence in every mainland state. The city is served by Rockhampton Airport , and Port Alma , located at the south end of the Fitzroy river delta. Rockhampton is renowned for its architecture, cuisine, and music; in particular for its jazz scene, and has been sometimes referred to as the " Melbourne of the North "; in reference to the city's tree-lined boulevards and laneways. The city's historic quarter

6063-477: Is usually accomplished by a powerful transmitter which generates noise on the same frequency as the target transmitter. US Federal law prohibits the nonmilitary operation or sale of any type of jamming devices, including ones that interfere with GPS, cellular, Wi-Fi and police radars. ELF 3 Hz/100 Mm 30 Hz/10 Mm SLF 30 Hz/10 Mm 300 Hz/1 Mm ULF 300 Hz/1 Mm 3 kHz/100 km Rockhampton Rockhampton

6192-668: The Allied Forces in the South-West Pacific . The AMP Building in Queen Street , Brisbane, (now the MacArthur Chambers ) was chosen for MacArthur's headquarters because of its central location and reinforced concrete roof. It was feared that the presence of all these high aerial towers would act as a navigational aid for Japanese aircraft seeking to attack MacArthur's headquarters. This accelerated

6321-611: The Berserker Range named after the Norse warrior " Baresark ". The Archer brothers took-up a run near Gracemere in 1855, and more settlers arrived soon thereafter, enticed by the fertile valleys. The town of Rockhampton was proclaimed in 1858, and surveyed to a design that closely resembled the Hoddle Grid of Melbourne , and consisted of a grid of wide boulevards and laneways, which was uncommon for Queensland cities. Within

6450-677: The Dreamtime Cultural Centre . The Capricorn district is the traditional home of the Darumbal Aboriginal people . The Darumbal (Tarumbul, Tharoombool) language region includes the city of Rockhampton extending south towards Raglan Creek and north towards the Styx River and inland along the Broad Sound Ranges. The Gangulu (Kangulu, Kanolu, Kaangooloo, Khangulu) language region includes

6579-606: The Fitzroy River , approximately 45 kilometres (28 mi) from where the river enters the Coral Sea , and some 600 kilometres (370 mi) north of the state capital, Brisbane . Rockhampton has a north and south side with three bridges connecting the two sides, one for trains and two for vehicles and people. Rockhampton lies just north of the Tropic of Capricorn in Central Queensland. A sculpture originally marking

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6708-595: The International Telecommunication Union (ITU), which allocates frequency bands in the radio spectrum for various uses. The word radio is derived from the Latin word radius , meaning "spoke of a wheel, beam of light, ray". It was first applied to communications in 1881 when, at the suggestion of French scientist Ernest Mercadier  [ fr ] , Alexander Graham Bell adopted radiophone (meaning "radiated sound") as an alternate name for his photophone optical transmission system. Following Hertz's discovery of

6837-656: The List of heritage listed buildings in Rockhampton . Rockhampton is governed by the Rockhampton Regional Council . The Council consists of a mayor and seven councillors. The Mayor is elected by the public, and the Councillors are elected from seven single-member divisions using an optional preferential voting system. Elections are held every four years. Tony Williams is the current mayor after

6966-513: The Mount Morgan Mine , which was at that time one of the most-productive gold mines in the world, laid the foundations for much of the city's Victorian architecture , and recast Rockhampton into a grand northern city. The economy of Rockhampton has strengths in tourism, health, and agriculture, with a GRP of $ 5.7 billion as of 2023. The Central Queensland University founded in 1967, has its main campus at Norman Gardens , and

7095-743: The National Broadcasting Service (NBS, later the ABC) for five years (since 31 January 1930). Radio station 4QR was officially opened in 1938, with transmission from the roof of the Central Automatic Exchange Building in Elizabeth Street. At the start of World War II , Brisbane's skyline was dominated by five high aerial towers, of which two served 4QG and one 4QR . A further two towers served commercial stations. Land acquisitions for

7224-504: The ionosphere without refraction , and at microwave frequencies the high-gain antennas needed to focus the radio energy into a narrow beam pointed at the receiver are small and take up a minimum of space in a satellite. Portions of the UHF , L , C , S , k u and k a band are allocated for space communication. A radio link that transmits data from the Earth's surface to a spacecraft

7353-519: The latitude was later moved into town to be more accessible to tourists. Although the Tropic of Capricorn is represented on maps as a "dotted line" that lies at 23 ° 26' 22", there is actually a bio-geographical overlap of Tropical and Temperate zones more than 500 kilometres (310 mi) wide; Rockhampton is roughly at its centre on the East Coast of Australia. The city is located on the banks of

7482-400: The radio spectrum into 12 bands, each beginning at a wavelength which is a power of ten (10 ) metres, with corresponding frequency of 3 times a power of ten, and each covering a decade of frequency or wavelength. Each of these bands has a traditional name: It can be seen that the bandwidth , the range of frequencies, contained in each band is not equal but increases exponentially as

7611-531: The skywave to reduce fading at the fringes of ground wave coverage at night Two smaller masts have also been erected at the site, one being to radiate the ABC NewsRadio service and the other as a standby mast for the 200m main mast. The main building lies on the western (high) side of the site. It was first used to accommodate the 4QR transmitter, which was shifted overnight on 23–24 March 1942. Other buildings include: Other original transmitters at

7740-561: The 1880s and '90s, sea ports were established on the coast, adjacent to the mouth of the Fitzroy River. Broadmount was on the northern side and Port Alma on the south. Railways were subsequently constructed to carry goods to the wharves at these locations, with the railway to Broadmount opening on 1 January 1898 and the line to Port Alma opening on 16 October 1911. Maintenance on the Broadmount line ceased in August 1929. The following month,

7869-438: The 1890s, and many of the town's substantial brick and stone public buildings date from this period. The historic streetscape of Quay Street still displays a number of substantial historic buildings, built when Rockhampton was envisaged as being capital of a state of North Queensland. Most prominent of these is the sandstone Customs House (1900), which today houses an information centre. Other important 19th-century buildings include

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7998-531: The 1920s with the introduction of broadcasting. Electromagnetic waves were predicted by James Clerk Maxwell in his 1873 theory of electromagnetism , now called Maxwell's equations , who proposed that a coupled oscillating electric field and magnetic field could travel through space as a wave, and proposed that light consisted of electromagnetic waves of short wavelength . On 11 November 1886, German physicist Heinrich Hertz , attempting to confirm Maxwell's theory, first observed radio waves he generated using

8127-451: The 2021 mayoral by-election following the resignation of long time mayor Margaret Strelow. Margaret Strelow won the mayoral elections in 2013, 2016 and March 2020. Strelow had also served as Mayor of the former City of Rockhampton from 2000 to 2008. The present Rockhampton Regional Council area was formed as a result of the 2008 amalgamation of four local government areas. These were the original City of Rockhampton which comprised most of

8256-542: The 4BH site was at Roghan Road near Neville Road, next to Fischle's. Bald Hills residents of the time were not impressed by this transfer of risk of Japanese attack to their area. As the Queensland segment of the National Broadcasting Service (NBS) was restricted to Brisbane, Rockhampton and Townsville , it was proposed to use high frequency ( short wave ) transmission to give some cover to

8385-604: The Archer brothers constructed a wool shed just downstream of a bar of rocks that prevented further upstream navigation from the coast. These rocks were incorporated with the traditional English term for a village, and the name "Rockhampton" was first coined by Charles Archer and the local Commissioner from Crown Lands, William Wiseman. In 1855, Scottish colonists and brothers William Thomas Elliott and George Mackenzie Elliot arrived at Gracemere and soon after, took up landholdings at Canoona , north of present-day Yaamba . Their father

8514-666: The Australian Café, the brothers renamed it the Busy Bee Café. During the Second World War, a US army base was established outside the city; it hosted up to 70,000 servicemen en route to action in the Pacific and New Guinea . On 2 March 1949, Rockhampton was severely damaged by a cyclone . The Fitzroy River Barrage was commissioned in 1971. The barrage has a capacity of 81,300 megalitres and holds back

8643-535: The Bald Hills centre were both new. It illustrates an important phase of the very rapid development of the National Broadcasting Service's Queensland operations. This phase began at a relatively early stage in the history of the radio broadcasting in Australia . It enabled access for the first time to radio services for communities in inland and remote centres, thereby reducing their isolation. The transmitter

8772-709: The Central Queensland Territorial Separation League, the women of Rockhampton established their own separation league in October 1892. The inaugural meeting of the Women's Central Queensland Territorial Separation League was held at the Rockhampton School of Arts and attended by 200 women. Their main focus was preparing a petition to Queen Victoria .  The introductory text set out their grievances and described

8901-474: The Earth's atmosphere has less of an effect on the range of signals, and line-of-sight propagation becomes the principal mode. These higher frequencies permit the great bandwidth required for television broadcasting. Since natural and artificial noise sources are less present at these frequencies, high-quality audio transmission is possible, using frequency modulation . Radio broadcasting means transmission of audio (sound) to radio receivers belonging to

9030-588: The Fitzroy River and its many tributaries and lagoons, the region continued to expand rapidly. In 1858, the town of Rockhampton was officially proclaimed. The town was surveyed at this time and the first sales of building allotments were held that year. In 1859, gold was discovered at Canoona. Miners rushed to the new field, using the site of Rockhampton on the Fitzroy River as the nearest navigable port. The Canoona field proved to be very disappointing and thousands of would-be gold seekers were left stranded at Rockhampton. Although many returned south, others stayed, adding to

9159-724: The Fitzroy River, approximately 40 kilometres (25 mi) from the river mouth. The Berserker Range lies on the eastern side of the city, with the Athelstane Range to the west. The coastal area to the east of the city is known as the Capricorn Coast , with the rapidly growing town of Yeppoon its major centre. Rockhampton experiences a humid subtropical climate ( Köppen: Cfa) with hot, humid summers and very mild, relatively dry winters with cool nights. The city receives 116.3 days of clear skies annually, primarily in winter. The highest recorded temperature in Rockhampton

9288-540: The Kensington Estate, described as just three miles from "the most rapidly rising town and district in the whole of the colonies" was advertised for sale. During the 1860s and '70s, Rockhampton developed as the main port for the developing Central Queensland hinterland, the main export at that time being wool. A Primitive Methodist Church opened in Fitzroy Street, Rockhampton, in January 1864. In

9417-441: The National Broadcasting Service was the first high frequency transmitter in Queensland and the second in Australia. It is the last of its type in the world and is a relic of a period when high frequency (short wave) transmissions were the most favoured means of broadcasting to country areas. It was used extensively on broadcasts to Papua New Guinea . It was at the vanguard of the era of shortwave transmission which started when it and

9546-713: The Post Office (1892), the Supreme Court House (1888), and St Joseph's Cathedral (1892). In September 1892 the Anglican Church in Rockhampton was the first new building in Rockhampton to be lit by electricity from the new gasworks. It was also the first church in Australia to be lit with electricity. In 1889 the people of Rockhampton established the Central Queensland Territorial Separation League ,

9675-523: The Rockhampton metropolitan area, the Shire of Fitzroy comprising Gracemere and surrounding districts, and the Shire of Mount Morgan around the town of Mount Morgan itself. The fourth local government area was the Shire of Livingstone which comprised the adjacent coastal towns and hinterland to the east and north of Rockhampton as well as some outlying Rockhampton suburbs. However, Livingstone Shire de-amalgamated from Rockhampton Region in 2014 following

9804-577: The Rockhampton township began in July 1856, when Richard Palmer travelled from Gladstone with an escort of Native Police under sub-Lieutenant Walter Powell to set up a store. Powell arrived at the site first and constructed the Native Police barracks. This was the first habitable British building established at Rockhampton and it was located on the south bank of the Fitzroy River at the end of Albert Street. With abundant grazing lands and waters from

9933-706: The Shark Nightclub, causing injuries and extensive damage to the building. The following year, the Factory Nightclub was also damaged by a bomb. It is not known who planted the bombs. In 2003, Rockhampton was the centre of significant national media interest after local teenager Natasha Ryan was found in the North Rockhampton home of her boyfriend, Scott Black, after being missing for five years. Serial killer Leonard Fraser had been charged with her murder, as her disappearance occurred in

10062-596: The US, these fall under Part 15 of the Federal Communications Commission (FCC) regulations. Many of these devices use the ISM bands , a series of frequency bands throughout the radio spectrum reserved for unlicensed use. Although they can be operated without a license, like all radio equipment these devices generally must be type-approved before the sale. Below are some of the most important uses of radio, organized by function. Broadcasting

10191-405: The air simultaneously without interfering with each other because each transmitter's radio waves oscillate at a different rate, in other words, each transmitter has a different frequency , measured in hertz (Hz), kilohertz (kHz), megahertz (MHz) or gigahertz (GHz). The receiving antenna typically picks up the radio signals of many transmitters. The receiver uses tuned circuits to select

10320-418: The anodes of the power output valves, duplicate pumps powered by 3-4 hp 2,900 RPM three-phase electric motors were installed in an adjoining room. A fan cooled external radiator was installed on a patio adjacent to the pump room. As the anodes operate at 12,000 volts, low conductivity cooling water was essential, and a still was installed to ensure a continual supply. The existing main vertical radiator

10449-464: The area in 1844 and 1846 and noted suitable land for grazing then. In January 1854, the New South Wales government proclaimed two new districts: Port Curtis and Leichhardt (roughly today's Fitzroy Region), and the Archer brothers returned in August 1855 to set up their pastoral run at Gracemere . The Fitzroy River provided a convenient waterway for shipping of supplies and produce, and

10578-414: The beam strikes a target object, radio waves are reflected back to the receiver. The direction of the beam reveals the object's location. Since radio waves travel at a constant speed close to the speed of light , by measuring the brief time delay between the outgoing pulse and the received "echo", the range to the target can be calculated. The targets are often displayed graphically on a map display called

10707-449: The companies experience difficulty finding local workers to fill vacancies. One meat processing plant is located at Lakes Creek, operated by Teys Australia (a Cargill joint venture) while the JBS meatworks is located at Nerimbera. The Teys Australia meatworks at Lakes Creek was previously owned by Kerry Packer 's Consolidated Meat Group. CMG temporarily closed the facility in 2002. It

10836-668: The continuous waves which were needed for audio modulation , so radio was used for person-to-person commercial, diplomatic and military text messaging. Starting around 1908 industrial countries built worldwide networks of powerful transoceanic transmitters to exchange telegram traffic between continents and communicate with their colonies and naval fleets. During World War I the development of continuous wave radio transmitters, rectifying electrolytic, and crystal radio receiver detectors enabled amplitude modulation (AM) radiotelephony to be achieved by Reginald Fessenden and others, allowing audio to be transmitted. On 2 November 1920,

10965-570: The current Bald Hills site commenced in 1940. The first aerial was erected on the site in 1941; it was constructed from 8 inches (200 mm) and 6 inches (150 mm) bore casing and was 262 feet (80 m) high. The transmitter building was made of brick with a fibro roof. It was built by Thomas Frederick of Days Road, Wilston , under a contract awarded in July 1941, and work had started by October 1941. The farm buildings were removed at about this time. In March 1942 General Douglas MacArthur arrived in Australia to be appointed supreme commander of

11094-466: The customer pays a monthly fee. In these systems, the radio signal is encrypted and can only be decrypted by the receiver, which is controlled by the company and can be deactivated if the customer does not pay. Broadcasting uses several parts of the radio spectrum, depending on the type of signals transmitted and the desired target audience. Longwave and medium wave signals can give reliable coverage of areas several hundred kilometers across, but have

11223-720: The eighth floor of the then new State Government Insurance Building (from 1933 known as the Taxation building) at the corner of George and Elizabeth Streets. The involvement of the Australian Broadcasting Commission (now the Australian Broadcasting Corporation, ABC) started in 1930, with the Postmaster General's Department (PMG) being responsible for technical operation. Major modifications were made to

11352-591: The employees of the Elliots. William Thomas Elliot and his men opened fire at random upon the group which fled after a short time. William and an employee were wounded (the employee reportedly died) and about seven of the local inhabitants were killed. Fellow colonist, Charles Archer of Gracemere and a group of Native Police troopers later pursued these Aboriginal people toward the east and punished them further. Local Aboriginal people friendly to Archer were also fired upon, killing one. Permanent British settlement at

11481-570: The existence of radio waves in 1886, the term Hertzian waves was initially used for this radiation. The first practical radio communication systems, developed by Marconi in 1894–1895, transmitted telegraph signals by radio waves, so radio communication was first called wireless telegraphy . Up until about 1910 the term wireless telegraphy also included a variety of other experimental systems for transmitting telegraph signals without wires, including electrostatic induction , electromagnetic induction and aquatic and earth conduction , so there

11610-413: The first commercial radio broadcast was transmitted by Westinghouse Electric and Manufacturing Company in Pittsburgh, under the call sign KDKA featuring live coverage of the Harding-Cox presidential election . Radio waves are radiated by electric charges undergoing acceleration . They are generated artificially by time-varying electric currents , consisting of electrons flowing back and forth in

11739-592: The first radio communication system, using a spark-gap transmitter to send Morse code over long distances. By December 1901, he had transmitted across the Atlantic Ocean. Marconi and Karl Ferdinand Braun shared the 1909 Nobel Prize in Physics "for their contributions to the development of wireless telegraphy". During radio's first two decades, called the radiotelegraphy era, the primitive radio transmitters could only transmit pulses of radio waves, not

11868-540: The floor and pictures falling off walls. The 1918 earthquake remains as the largest to have ever hit Queensland since European settlement. Restaurant proprietors, Emanuel, William and Nicholas Economos, trading as the Economos Bros., ran their business in East Street, Rockhampton. East Street was a bustling metropolis when the brothers opened their traditional Greek café in the 1920s. Previously known as

11997-618: The frequency increases; each band contains ten times the bandwidth of the preceding band. The term "tremendously low frequency" (TLF) has been used for wavelengths from 1–3 Hz (300,000–100,000 km), though the term has not been defined by the ITU. The airwaves are a resource shared by many users. Two radio transmitters in the same area that attempt to transmit on the same frequency will interfere with each other, causing garbled reception, so neither transmission may be received clearly. Interference with radio transmissions can not only have

12126-506: The immense size of Queensland: being twelve times the area of England and Wales, and larger than France, Germany, Spain and Portugal combined. The State Library of Queensland holds the original petition, signed by over 3000 women who were in support of Central Queensland becoming a separate state. The petition was forwarded to Queen Victoria but was dismissed by the Premier of Queensland, Sir Samuel Walker Griffith. The City of Rockhampton

12255-982: The late Douglas Sanderson, were presented by the Institution of Engineers Australia , to the John Oxley Library in 1994. [REDACTED] This Misplaced Pages article was originally based on National Broadcasting Service, Radio Transmission Centre , entry number 100631 in the Australian Heritage Database published by the Commonwealth of Australia 2018 under CC-BY 4.0 licence , accessed on 6 September 2018. [REDACTED] Media related to Bald Hills radiator at Wikimedia Commons Radio transmission In radio communication , used in radio and television broadcasting , cell phones, two-way radios , wireless networking , and satellite communication , among numerous other uses, radio waves are used to carry information across space from

12384-402: The longest transmission distances of any radio links, up to billions of kilometers for interplanetary spacecraft . In order to receive the weak signals from distant spacecraft, satellite ground stations use large parabolic "dish" antennas up to 25 metres (82 ft) in diameter and extremely sensitive receivers. High frequencies in the microwave band are used, since microwaves pass through

12513-507: The mercury vapour rectifiers, had a personality and character which is totally lacking in the sterile steel boxes, the state of the art highly complex, almost non repairable transmitters of the 90s." Particular qualities of the STCA880A are its robustness and its reliability, evidenced by the decades of high quality service it gave before it was finally retired, mainly because the valves vital for its operation finally went out of production. It

12642-610: The nearby Central Park. The Rockhampton Botanic Gardens are one of the oldest public gardens in the country, being founded in 1869 and is also the location of the Rockhampton War Memorial , as well as the Rockhampton Zoo . Rockhampton has nationally prominent cultural institutions, including; the Rockhampton Museum of Art (RMOA), one of the most extensive regional galleries in Australia, and

12771-472: The need for legal restrictions warned that "Radio chaos will certainly be the result until such stringent regulation is enforced." The United States Navy would also play a role. Although its translation of the 1906 Berlin Convention used the terms wireless telegraph and wireless telegram , by 1912 it began to promote the use of radio instead. The term started to become preferred by the general public in

12900-508: The need to shift the transmitters out of the city centre. The first transmission from the Bald Hills site was of 4QR, on 24 March 1942, using the transmitter moved the previous night from the Central Telephone Exchange in the city. In April 1942, the 4QG transmitter was also relocated to Bald Hills but not to this site but to another Bald Hills site leased from the commercial station 4BH . Known as Fischle's Jam Factory,

13029-636: The new town's population. Conflict with Aboriginal people in the region continued and further massacres occurred. In 1859, John Arthur Macartney attempted to stock his cousin's Belmont property just to the north of Rockhampton when a shepherd was killed by local Aboriginal men. 2nd Lieutenant Frederick Carr of the Native Police together with his troopers, the Macartneys, Peter Fitzallan MacDonald and Henry Brisdon, formed an armed group which set out to track down those responsible. The group followed

13158-539: The only provincial city in Queensland to have a street tramway. Purrey steam trams ran on a number of routes throughout South Rockhampton, totalling 10 kilometres (6.2 mi) of track. The discomfort of passengers riding in steam trams in a tropical climate in part led to their demise in 1939, replaced by a bus network run by the City Council. Strong shaking was felt in Rockhampton when the "Great Queensland Earthquake of 1918" occurred on 7 June 1918. The earthquake

13287-544: The period in which Fraser had abducted and murdered other women and girls. An anonymous tip-off during Fraser's trial led to the discovery of Ryan. Despite Ryan's discovery, Fraser's defence did not seek a mistrial and Fraser was convicted of the murders of other women and girls and was given an indefinite life sentence. On 20 February 2015, Rockhampton was severely damaged by Cyclone Marcia damaging hundreds of homes and businesses with wind speeds over 150 kilometres per hour (93 mph) recorded in Rockhampton. Major flooding

13416-505: The picture quality to gradually degrade, in digital television picture quality is not affected by poor reception until, at a certain point, the receiver stops working and the screen goes black. Government standard frequency and time signal services operate time radio stations which continuously broadcast extremely accurate time signals produced by atomic clocks , as a reference to synchronize other clocks. Examples are BPC , DCF77 , JJY , MSF , RTZ , TDF , WWV , and YVTO . One use

13545-451: The radio frequency spectrum it is located, so bandwidth is a measure of information-carrying capacity . The bandwidth required by a radio transmission depends on the data rate of the information (modulation signal) being sent, and the spectral efficiency of the modulation method used; how much data it can transmit in each kilohertz of bandwidth. Different types of information signals carried by radio have different data rates. For example,

13674-409: The radio signal desired out of all the signals picked up by the antenna and reject the others. A tuned circuit (also called resonant circuit or tank circuit) acts like a resonator , similar to a tuning fork . It has a natural resonant frequency at which it oscillates. The resonant frequency of the receiver's tuned circuit is adjusted by the user to the frequency of the desired radio station; this

13803-451: The radio spectrum, the right to use a frequency band or even a single radio channel is bought and sold for millions of dollars. So there is an incentive to employ technology to minimize the bandwidth used by radio services. A slow transition from analog to digital radio transmission technologies began in the late 1990s. Part of the reason for this is that digital modulation can often transmit more information (a greater data rate) in

13932-456: The radio waves that carry the information through the air. The modulation signal is used to modulate the carrier, varying some aspect of the carrier wave, impressing the information in the modulation signal onto the carrier. Different radio systems use different modulation methods: Many other types of modulation are also used. In some types, a carrier wave is not transmitted but just one or both modulation sidebands . The modulated carrier

14061-545: The rest of Queensland. VLQ first went to air on 17 February 1943, transmitted by STCA880A. Land acquisitions for the present site continued through to July 1943 when the Australian Government resumed the 114 acre (46ha) property from J W Guy. The transmitter building was extended from 1945 to 1946, while the existing vertical radiator was erected in 1947. The building was further extended 1962, and has since been internally modified at least twice when equipment

14190-481: The same digital modulation. Because it is a fixed resource which is in demand by an increasing number of users, the radio spectrum has become increasingly congested in recent decades, and the need to use it more effectively is driving many additional radio innovations such as trunked radio systems , spread spectrum (ultra-wideband) transmission, frequency reuse , dynamic spectrum management , frequency pooling, and cognitive radio . The ITU arbitrarily divides

14319-537: The site included: The medium wave transmitters were eventually replaced with solid-state Nautel ND series transmitters that use a Class-D amplifier containing MOSFET devices. The shortwave transmitters were then decommissioned, the VLQ9 and VLM4 services were discontinued and the shortwave curtain array antennas removed. The original VLQ transmitter is completely preserved and housed in its original 1943 location. The VLQ transmitter STCA880A (1943) constructed for

14448-473: The site lies essentially in its connection with the transmitters. The aerial, erected in 1947, has become a very well known local landmark. Their significance attaches to the transmitting equipment housed in the main building, a unit purpose built in 1941-42 and modified or extended on at least four occasions since. Two series of photographs were taken of the erection of the first aerial in 1941 and of its spectacular demolition in 1987. These, with annotations by

14577-437: The south and Hoyland Street in the east. The VLQ STCA880A transmitter is a very early model high powered (10 kW) high frequency transmitter. It is built from very old technology, its design and construction pre-dating both the transistor and the silicon chip . Relying on extremely large glass and metal radio valves , the final amplifier valves requiring a water cooling system , the transmitter in operation presented

14706-484: The suburbs of Glenlee, Rockyview, and Glendale. The agricultural sector, specifically the cattle trade, is a dominant industry in Central Queensland. The latter has been visually represented around Rockhampton City with a set of seven large statues of bulls known as the ' Big Bulls '. Two large abattoirs are located on the south-eastern outskirts of Rockhampton provides employment for people living in Rockhampton and also for refugees from overseas who are recruited when

14835-541: The towns of Clermont and Springsure extending south towards the Dawson River , and includes parts of Rockhampton and South Rockhampton. The British colonisation of the area began in 1853, when the Archer brothers , Charles and William, who were seeking grazing lands arrived in the Rockhampton area. They were acting on information from earlier expeditions by Ludwig Leichhardt and Thomas Mitchell , who had explored

14964-475: The tracks and "dispersed" them. One account of this incident describes how around hundred of the tribe were rounded up and "it ended in the usual way and the bulk of the wild mob were shot." By 1861, the town boasted a regular newspaper, banks, court house, and school of arts. Direct shipments of imported goods and migrants from the United Kingdom began to be received during the 1860s. In 1862, land in

15093-582: The transmitter during the ABC's use of the transmitter. In 1935, a survey team from the Postmaster General (PMG) Research Laboratories in Melbourne selected the Bald Hills site, then a farm, as a future location for a possibly high-powered transmitter for 4QG, but no land acquisition occurred at that time. At that stage radio station 4QG had been in existence for ten years (since 27 July 1925), and

15222-431: The transmitting antenna also serves as the receiving antenna; this is called a monostatic radar . A radar which uses separate transmitting and receiving antennas is called a bistatic radar . Radiolocation is a generic term covering a variety of techniques that use radio waves to find the location of objects, or for navigation. Radio remote control is the use of electronic control signals sent by radio waves from

15351-510: The weak radio signal so it is stronger, then demodulates it, extracting the original modulation signal from the modulated carrier wave. The modulation signal is converted by a transducer back to a human-usable form: an audio signal is converted to sound waves by a loudspeaker or earphones, a video signal is converted to images by a display , while a digital signal is applied to a computer or microprocessor, which interacts with human users. The radio waves from many transmitters pass through

15480-406: The wharf caught fire and the line was effectively closed in July 1930. The line to Port Alma closed on 15 October 1986. The significant gold deposit at Mount Morgan to the southwest was discovered in the 1880s, and Rockhampton became the main port through which the wealth of Mount Morgan gold was channelled. Due to the wealth of Mount Morgan, Rockhampton weathered the severe economic depression of

15609-469: Was 45.3 °C (113.5 °F), while the lowest was −1.0 °C (30.2 °F). Furthermore, the highest recorded 24-hour rainfall total was 348.0 millimetres (13.70 in) due to the January 2013 Eastern Australia floods . In summer, Rockhampton is subject to summer thunderstorms, and lying within the cyclone risk zone, it has experienced several large floods cyclones since European settlement. This

15738-682: Was James Elliot, 3rd Laird of Wolfelee House near Hawick in Scotland. One of their other brothers was Walter Elliot of the East India Company and secretary to the governor of the Madras Presidency . In January 1856, after a massacre of local Aboriginal people perpetrated by Lieutenant John Murray of the Native Police at nearby Nankin Creek, some 200 Aboriginal men, women and children came to Canoona and began shouting at

15867-598: Was a need for a more precise term referring exclusively to electromagnetic radiation. The French physicist Édouard Branly , who in 1890 developed the radio wave detecting coherer , called it in French a radio-conducteur . The radio- prefix was later used to form additional descriptive compound and hyphenated words, especially in Europe. For example, in early 1898 the British publication The Practical Engineer included

15996-777: Was experienced in the upper reaches of the Fitzroy River after more than 250mm were recorded. The cyclone left about 100,000 properties across Central Queensland without power. According to the 2016 census , there were 76,985 people in Rockhampton. Aboriginal and Torres Strait Islander people made up 7.2% of the population. 82.8% of people were born in Australia. The next most common countries of birth were New Zealand 1.4%, England 1.3%, Philippines 1.1%, India 0.6% and Vietnam 0.4%. 86.4% of people spoke only English at home. Other languages spoken at home included Vietnamese 0.5%, Tagalog 0.5%, Portuguese 0.3%, Filipino 0.3% and Mandarin 0.3% The most common responses for religion were Catholic 26.5%, No Religion 22.6% and Anglican 17.1%. The town lies on

16125-464: Was felt from Mackay in the north, to Grafton in New South Wales, and west to Charleville . Estimated to have reached a 6.0 magnitude, the earthquake caused some damage to buildings including chimney stacks crumbling, plaster being dislodged from walls and ceilings, water tanks bursting and trees being uprooted. Houses and buildings experienced considerable swaying with crockery smashing on

16254-456: Was in either full-time or reserve service for forty five years, from 1943 until 1988. The Bald Hills unit was the third of its type, preceded by one at Laverton and another at Ballarat , both for the RAAF . It was the first NBS short wave transmitter in Queensland and the second in Australia. Its NBS predecessor, code named VLR, was operated from Victoria . It was not of the same type. To cool

16383-487: Was proclaimed in 1902. The rail connection south to Brisbane was completed in 1903, but it was not until 1921 that the northern connection to Mackay was finally completed. A railway west from Rockhampton was started in 1867 and by 1892 had reached the terminus at Longreach , 700 kilometres (430 mi) away. This further strengthened Rockhampton's role as the port for the whole of Central Queensland. A passenger tramway began operating on 16 June 1909, making Rockhampton

16512-564: Was reopened in 2004, when Consolidated Meat Group announced they had formed a joint venture with Teys Australia. In 2011, Cargill bought out CMG's share in the company. Due to drought, floods, general economic conditions and disputes with workers, both facilities have experienced a number of closures over the years including the closure of the Lakes Creek meatworks from 2002 until 2004, but they are both currently operating as normal. The Central Queensland Livestock Exchange at Gracemere

16641-483: Was upgraded: once in 1968 and again in about 1994. In two later stages, (c 1970, 1980) there were minor reductions in the land holding of the site, for road widening and subdivisional redevelopment. The current area of the site is 43ha. The National Broadcasting Service Radio Transmission Centre is an approximately 43 hectares (110 acres) site at 99 Kluver Street on the corner of Bracken Ridge Road, Bald Hills, facing west into Kluver Street and bounded by Taragon Street in

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