25 September 1996: Noni Hazlehurst narrates the documentary The Edge Of Instinct (ABC), following the emotional journey of couples going through IVF.
25 September 2005: The Nine Network presents the special 50 Years 50 Shows, counting down the top 50 shows to commemorate the 50th year of Australian television.
25 September 2010: The Seven Network replaces its high-definition channel 7HD with a new channel, 7mate
25 September 2004: Ten aired the 2004 AFL Grand Final between Brisbane and Port Adelaide the first Grand Final without any Victorian clubs competing
25 September 2010: Seven aired the last ever Drawn Grand Final between Collingwood and St Kilda with the above-mentioned channel launching after the match.
25 September 2000: Cathy Freeman’s gold medal win at the Sydney Olympics drew a record TV audience for Channel 7 with 6.3 million people watching her iconic race now etched in Australian sporting folklore
I believe 7mate soft-launched with the AFL Grand Final in HD simulcast, before breakaway programming began after the AFL coverage.
wasn’t really a record as the Opening Ceremony was watched by around 10 million a week earlier 
Maybe i’m remembering incorrectly, but I recalll there was some conjecture that the number is unlikely to be realistic (it was discussed at the time the Matildas had large ratings for the WWC)
26 September 2010: The Nine Network replaces its high-definition channel 9HD with a new channel, Gem
September 27 of 1997 - The AFL Grand Final from the Melbourne Cricket Ground in Richmond, Victoria is broadcasted on Seven with Adelaide winning maiden Senior premiership defeating St Kilda by 31 points.
September 27 of 2003 - The AFL Grand Final from the Melbourne Cricket Ground in Richmond, Victoria is broadcasted on 10 for the second year running, once again featuring Collingwood and Brisbane with the latter winning it’s third premiership in a row (Final Mens Senior Premiership before 2024).
September 27 of 2008 - The AFL Grand Final is broadcasted on Seven for the first time since 2001 (2,555 days) featuring Geelong and Hawthorn with Hawthorn winning by 26 points.
September 27 of 2014 - The AFL Grand Final is broadcasted on Seven with Hawthorn winning back to back premierships defeating Sydney by 63 Points.
A general note a lot of posters, the word is “broadcast” in all tenses.
29 September 1991: The Seven Network premieres mini-series Rose Against The Odds, depicting the story of champion boxer Lionel Rose.
29 September 1993: The documentary So Help Me God (ABC) follows a group of defendants as they weave their way through the justice system. Meanwhile, The Republic — Court In The Act (SBS) presents a courtroom scenario with barristers, a judge, expert witnesses and a jury of everyday Australians setting out to inform viewers about the republic debate.
29 September 1998: The Nine Network premieres drama series Stingers, starring Peter Phelps, Kate Kendall, Anita Hegh, Ian Stenlake, Jessica Napier and Joe Petruzzi.
29 September 2001: The 2001 AFL Grand Final — Essendon versus Brisbane Lions — is live on the Seven Network and pay-TV channel C7 Sport. The match marked the end of Seven’s coverage of VFL/AFL after 45 years (with the exception of 1987) until it would re-gain the rights (in partnership with Network Ten and Foxtel) from season 2007.
29 September 2004: SBS premieres eight-part documentary series Everyone Loves A Wedding, exploring how 16 culturally diverse couples cope with their big day.
29 September 2008: SBS premieres motoring series Top Gear Australia with Warren Brown, Charlie Cox and Steve Pizzati.
29 September 2010: ABC1 premieres Strictly Speaking, a public speaking competition hosted by Andrew Hansen (The Chaser)
Top Gear Australia…. Oh boy, not a patch on the BBC series. A case study in how some concepts don’t always translate well across nations….
30 September 1977: The Seven Network premieres drama series Glenview High in Sydney. Melbourne’s HSV7 follows the next week.
30 September 1982: The XII Commonwealth Games in Brisbane are officially opened. ABC is the host Australian broadcaster with replays and highlights on the Nine Network.
YouTube: pugsley2005
30 September 1996: Harry Connick Jnr and Chris Isaak host the 10th annual ARIA Awards (Network Ten) live from the Sydney Convention Centre.
30 September 2009: The cast of Hey Hey It’s Saturday are reunited for the first of two specials on the Nine Network almost ten years after the show was cancelled. Network Ten premieres reality contest Celebrity MasterChef, and ABC1 premieres Hungry Beast, a combination of comedy and current affairs by aspiring talent
1 October 1977: The rematch of the 1977 VFL Grand Final — North Melbourne versus Collingwood — is live on the Seven Network with a replay on ABC.
1 October 2001: The Nine Network premieres prime-time interview series The Ray Martin Show.
1 October 2004: The community TV show Blokesworld makes the move to Network Ten, premiering in a late Friday night timeslot.
1 October 2009: Showcase premieres the drama series Tangle, starring Kat Stewart, Justine Clarke, Ben Mendelsohn, Lincoln Younes, Catherine McClements, Matt Day and Joel Tobeck.
1 October 2018: ABC Kids premieres cartoon series Bluey.
And horny bogans of Australia rejoiced. 
A momentous day for Australone kids, culture and parents all around. 
October 1 of 2000: Approximately a television audience of 6,641,000 around Australia were tuned in to Seven to watch the Sydney Olympics Closing Ceremony following 16 days of exciting multi-sports action. During the same evening, ABC scheduled The Greatest Wildlife Show on Earth, Deceit and Over the Top with Franz while Nine and 10 scheduled movies in The Temptations, Beethoven and The Bad Boys respectively.
2 October 1978: The 0-10 Network premieres its new early afternoon line-up — game shows Pyramid Challenge and Perfect Match (no relation to the 1980s show of the same name) and variety/chat show The Steve Raymond Show.
2 October 1995: Richard Stubbs and special guest Janet Jackson host the ARIA Awards (Ten) from the Sydney Convention and Exhibition Centre.
2 October 2006: The Nine Network premieres flashback series What A Year, hosted by Mike Munro and Megan Gale.
2 October 2007: SBS televises the The Deadly Awards from the Sydney Opera House Concert Hall.
2 October 2012: The biographical telemovie Underground: The Julian Assange Story is a rare ratings success for Network Ten.
3 October 1966: ABC premieres afternoon series Be Our Guest, a curious mix of drama, music and interviews, with a cast including Jacki Weaver, Lorraine Bayly, Gordon Glenwright, Jack Allan and Sean Scully. Guests in the first episode include pop star Normie Rowe and French singer Jean Sablon.
3 October 1991: ABC’s coverage of the 1991 Rugby World Cup, being held in France and the United Kingdom, begins with late-night coverage of the opening ceremony and the first match between England and New Zealand.
3 October 1993: The Nine Network premieres three-part documentary series Beyond Highway Number One, featuring adventurer Malcolm Douglas‘ journey around Australia on the road.
3 October 1998: ABC and the Nine Network present a full evening of Federal Election coverage from the National Tally Room in Canberra. The Seven Network presents an hour of coverage late in the evening, hosted by Paul Barry and Glenn Milne, and Ten News‘ late bulletin includes an election report. SBS‘ World News At Nine presents a special Saturday night edition.
3 October 2001: Network Ten presents the special Big Brother’s Starlight Challenge. Big Brother contestants star in a pantomime at Sydney’s Lyric Theatre, narrated by Gretel Killeen. Includes guest appearances by Bert Newton, Rove McManus and cast members of Neighbours and The Secret Life Of Us. The Nine Network presents the 15th ARIA Awards from Sydney’s Capitol Theatre, hosted by David Campbell.
3 October 2003: Pre-school children’s series Hi-5 celebrates its 200th episode.
4 October 1978: Melbourne’s ATV0 screens The Last Tasmanian, a two-hour documentary tracing the genocide of the Tasmanian Aborigines, starting with the arrival of white man in 1803 and culminating with the death of Truganini – the Last Tasmanian – in 1876. Sydney’s TEN10 aired the documentary a month later.
4 October 1983: The Seven Network premieres mini-series All The Rivers Run in Melbourne. Sydney’s ATN7 followed a week later.
4 October 1987: With the Seven Network having rights to both the annual James Hardie 1000 motor racing from Bathurst and the Davis Cup tennis, on this one occasion when both fell on the same date the tennis coverage was seconded to SBS. ABC premieres Go Fish Australia, a 13-part documentary series looking at the recreational industry of fishing in Australia, hosted by John Meillon.
4 October 1995: ABC premieres Bordertown, the ten-part series set in a 1950s migrant centre, starring Hugo Weaving, Christine Tremarco and Joe Petruzzi.
4 October 1998: Network Ten premieres The Ten Out-Take Files. Penny Cook presents bloopers from Network Ten shows including Neighbours, State Coroner, Medivac and Prisoner.
4 October 2007: Network Ten premieres children’s drama series Wormwood.
4 October 2010: Network Ten and Foxtel begin coverage of the XIX Commonwealth Games from Delhi, India
5 October 1978: ABC premieres panel game show Micro Macro, hosted by Noel Ferrier with Carol Raye and Jimmy Hannan.
5 October 1998: The Nine Network premieres animated series Skippy: Adventures In Bushtown, featuring the voices of Jamie Oxenbould, Robyn Moore and Keith Scott.
5 October 2000: The Nine Network premieres Sam And The Fatman, a sports/comedy show hosted by Sam Newman (The Footy Show, Melbourne) and Paul ‘Fatty’ Vautin (The Footy Show, Sydney) and regulars Shane Crawford, Phil Kearns and Ryan Girdler.
5 October 2004: The Seven Network premieres Dancing With The Stars with Daryl Somers and Sonia Kruger.
5 October 2005: Network Ten premieres Australian Princess, hosted by Jackie O, followed by the premiere of comedy series Merrick And Rosso: The B-Team.
7 October 1974: TV stations commence test pattern transmissions in colour.
Source: The Australian Women’s Weekly
7 October 1976: The Seven Network presents the inaugural Sammy Awards in partnership with TV Times and the Variety Club Of Australia. Hosted by David Frost and held at the Sydney Opera House.
7 October 1989: SBS screens the five-hour film The Mahabharata, director Peter Brook’s adaptation of the book which forms the basis of India’s mythology. Given the movie’s long length SBS have made a rare allowance to insert breaks into the presentation, but these are only placed at points which separate the three significant stages in the story.
7 October 1990: The Seven Network premieres mini-series Jackaroo, starring Annie Jones and David McCubbin. ABC presents Esso Night At The Opera, featuring Les Huguenots, the final performance of Dame Joan Sutherland.
7 October 1992: ABC premieres two-part mini-series Frankie’s House, starring Iain Glen, Ally Fowler and Kevin Dillon, telling the story of a group of young photo journalists during the Vietnam War.
7 October 1999: ABC premieres three-part documentary series Federation, looking at the struggles not just in forming a nation but in forming a democracy.
7 October 2007: The Nine Network premieres the Australian version of The Singing Bee, hosted by Joey Fatone, followed by factual series Dirty Jobs with Jo Beth Taylor and Ben Dark.
