Question: How far from Sydney is the town in which the radio station 2MAX TH is based ?

Context paragraphs:
Wireless Weekly: Wireless Weekly was Australia's first news-stand wireless magazine (not counting the "AWA monthly"), published in 1922 in Sydney by W.J. Maclardy, a founder of commercial radio station 2SB (later changed to 2BL).  It arose from conversations between Florence Violet (Vera) McKenzie OBE (née Wallace), aka 'Violet Wallace, 'Vera Wallace' and later 'Mrs Mac' (1890-1982), who owned a wireless shop in the Royal Arcade, Sydney, Ron Marsden her engineer, and Maclardy.  The front cover featured a photo of amateur radio activity.

List of Sydney radio stations: Radio in Sydney became a popular tool for politics, news, religion, and sport and has managed to survive despite the introduction of television and the internet.  The first long range (520 km) coastal radio station was established in 1911.  In 1921, amateur radio broadcasters commenced transition.  The first radio licence in Australia was granted to Charles Maclurcan for station 2CM.  Commencing in 1923, 2SB is the second official station to be licensed.  Sydney's first official station 2FC commenced service in 1924.  In 1935, the studios of the ABC install a disc recorder, enabling the recording of programs to occur for the first time.  Talk radio was introduced on 2SM in 1967.  In 1974, 2MBS commences broadcasting as the first full-time FM station in Australia, playing classical music 24 hours a day.  Finally, in 1975, multicultural radio is launched with the formation of 2EA.

2MAX: 2MAX FM is a community radio station based in Narrabri, NSW, Australia.  The station has been broadcasting for over 15 years to the regional area after being granted a full-time licence in 2000.

Graeme Gilbert: Graeme Gilbert (born 15 April 1950) is the host of nightly radio program "Talk Tonight with Graeme Gilbert" on Sydney radio station 2SM and the Super Radio Network.  He has hosted the show for over a decade and has interviewed notable people including John Howard, the former Prime Minister of Australia.  Gilbert has received a B&T Award for Best News Presenter and a RAWARD for Best Current Affairs Commentator.  Gilbert ran as a Liberal Party candidate for the division of Franklin, Tasmania in the 1993 Australian federal election.  He lost with 9.86% swing against him.

John Stanley (radio broadcaster): John Stanley is an Australian radio broadcaster, who is currently the co-host of the breakfast show on Sydney radio station 2UE, a station he has worked at since the 1990s.

Marcin Jaskulski: Marcin Jaskulski (born 11 November 1977) is a Polish-born Australian journalist based in the north-western New South Wales town of Bourke.  He worked at the regional Indigenous radio station 2CUZ FM.  The radio station broadcasts to many towns of New South Wales, including Walgett, Bourke and Brewarrina.  Jaskulski writes for a number of publications.

Narrabri: Narrabri is a town and seat of Narrabri Shire local government area in the North West Slopes, New South Wales, Australia on the Namoi River, 521 km northwest of Sydney.  It sits on the junction of the Kamilaroi Highway and the Newell Highway.  At the 2016 census, Narrabri had a population of 7,606.

Radio 2XG: Radio station 2XG, also known as the "Highbridge station", was an experimental station located in New York City and licensed to the De Forest Radio Telephone and Telegraph Company from 1915-1917 and 1920-1924.  In 1916 it became the first radio station employing a vacuum-tube transmitter to make news and entertainment broadcasts on a regular schedule, and, on November 7, 1916, became the first to broadcast U.S. presidential election returns by spoken word instead of Morse code.

Greek Radio (Australia): Greek Radio is a narrowcast radio station based in Revesby, broadcasting to the Sydney area.  The station broadcasts music and talk in Greek as well as relaying Rik 3 from Cyprus.  The station started as a Greek program on community radio station 2NBC in 1983.  The group later purchased a narrowcast licence and began transmitting on 1683 AM in 1996.

Elizabeth Jackson (radio journalist): Elizabeth Jackson is an Australian Broadcasting Corporation journalist who produces and presents the "Saturday AM" programme on ABC Local Radio, and "Correspondents Report", which airs on Sundays on ABC Radio National.  She has previously worked on Sydney radio station 2GB, and for ABC Television's and Lateline programmes.

Supporting paragraphs: 2MAX Narrabri
Answer: 521 km