Meldrum has featured on the Australian music scene since the mid-1960s, first with his writing for Go-Set (1966–74), a weekly teen newspaper, then during his tenure with Countdown and subsequent media contributions.

[a] His father was Robert Meldrum (7 April 1907 – 1978), a farmer from Caniambo (25 kilometres (16 mi) from Shepparton) and then a World War II army sergeant (Service No.

[7] Meldrum moved around during childhood and grew up largely with one of his grandmothers in Quambatook, where he attended the local primary school alongside future country music artist John Williamson.

[8] During The Beatles' tour of Australia in June 1964, Meldrum was captured by TV cameras climbing atop the bonnet of their car shortly after arrival at Melbourne airport.

[11]: 22–31 [15][16] By social networking and building a list of industry contacts, Meldrum was able to cover many facets of the local scene; his gossip columns informed not only general readers but also other musicians and, according to Frazer, they were the major reason people continued reading Go-Set.

[22] Meldrum's repertoire included miming to Peter and Gordon's "Lady Godiva", The New Vaudeville Band's "Winchester Cathedral" and George Formby's "Why Don't Women Like Me?".

[3][11]: 22–31  He moved on to another ATV-0 music show, Uptight, hosted by Ross D. Wyllie, which was broadcast for four hours on Saturday mornings with live bands and acts miming their own material.

[3][14] From January 1968, Meldrum relocated to London, reporting in Go-Set on The Groop's efforts to break into the United Kingdom market; he also wrote about the English rock music scene.

[15] While there, Meldrum extended his networking to international contacts, including meeting Apple Records executive, Terry Doran, who introduced him to his idols, Paul McCartney and John Lennon.

[19] In collaboration with Armstrong's house engineer John Sayers, Meldrum radically transformed "The Real Thing" from Young's original vision of a simple acoustic chamber ballad backed by strings, into a heavily produced studio masterpiece, extending it to an unheard-of six minutes in length (with encouragement from Rofe) and overdubbing the basic track with many additional instruments, vocals and sound effects.

[22][31] Shrimpton decided an editorial was needed, so Meldrum provided a weekly Rock Report from mid-1975 which was renamed "Humdrum" by guest host John Paul Young, and by year's end he had become the face of the series.

[12][31][32] The advent of colour TV in March 1975 coincided with a major shift in the direction of local popular music, and was vital in the national success for artists such as Skyhooks and Sherbet.

[29] Its use of film-clips, by both established and developing overseas acts (which rarely toured Australia), made Countdown an important venue for breaking new songs and new artists.

Meldrum was attributed as Willie Everfinish (a play on "will he ever finish") [11]: 86 [36] For its lead single, he wanted the A-side as "Lies", taking weeks to produce it, and his preferred B-side, "Don't Fall in Love", was rushed in three hours.

"[39]: 33  In July 1978 Michelle Morris of The Canberra Times described Meldrum as "sometimes outrageous, accident-prone and stumbling ... [who] has become an authority in the industry and often a promotional clip has only to be played on Countdown for a record to take off in the charts.

[43] In August 1980, Gregg Flynn of The Australian Women's Weekly was on set during the taping of an episode which featured INXS, Doc Neeson (The Angels), Daryl Braithwaite (ex-Sherbet) and Toy Love.

"[46] His appointment to the show had had "TV critics whipping themselves into a lather of hysterical accusations that the coiffured host was at best a cruel joke and at worst a danger ... [with his] mangled monologues as being detrimental to young people's vocabulary.

[47] Big winners were Cold Chisel with seven awards, which were not collected; the group performed the last live number, "My Turn to Cry", to close the show and then trashed their instruments and the set.

[49] During December he used his industry contacts to organise a charity single for research on fairy penguins, he produced the recording of a cover of Lennon, Ono & Plastic Ono Band's "Happy Xmas (War Is Over)" by The Incredible Penguins with Angry Anderson (Rose Tattoo), Brian Canham (Pseudo Echo), Scott Carne (Kids in the Kitchen), John Farnham, Venetta Fields, Bob Geldof, Steve Gilpin (ex-Mi-Sex), Colin Hay (Men at Work), Hewett, Keays (ex-The Masters Apprentices), Brian Mannix (Uncanny X-Men), Wendy Stapleton (Wendy & the Rocketts) and Chris Stockley (ex-Axiom, The Dingoes).

Despite some episodes of ineptitude, Meldrum became a major star in his own right and was a champion of local talent and regularly used the show to pressure radio stations to play more Australian music.

[32] As a result of his efforts, the show was able to make overnight hits of songs and performers it featured, and through the late 1970s and early 1980s it was a key factor in determining the direction of Australian popular music.

He saluted the music industry and fans, then bared his shaved head in imitation of Midnight Oil's Peter Garrett and expressed regret that they had never appeared on the show.

[11]: 137 [29][36] Dave Warner, musician and writer, described Meldrum's impact "[he] was loved, loathed, reviled, respected, but above all, watched... You simply couldn't ignore [him] nor could the Australian music industry.

"[39]: 132 In November 1998, Brian Mannix (ex-Uncanny X-Men) wrote and directed a stage play, Countdown: The Musical Comedy, with Meldrum portrayed by Michael Veitch.

[12] Body Beat issued electronic and disco music locally for various international artists, including Joyce Sims, Hanson & Davis, Joy Peters, and Mozzart (aka Paul Lander).

However, in 1993, when Meldrum received his ARIA Special Achievement Award for services to the music industry he provided one of the longest acceptance speeches in the ceremony's history.

[10] That his extensive general knowledge extended beyond popular music was less well known until, as a contestant on a celebrity edition Who Wants to Be a Millionaire?, he won $500,000 for a charity, which was the equal-biggest win on the Australian version of the program until October 2005), by using his phone a friend to ring Red Symons of Skyhooks fame (who also performed well on the show when he was in the hot seat, also reaching the $500,000 mark but failing the question).

[77] Samuel Johnson, in an emotionally-charged interview on The Morning Show, when asked to comment on the incident, expressed strong disappointment, frustration and concern with repeated patterns in Meldrum's behaviour.

[78] On 19 January 2023, new video footage emerged showing that Meldrum had previously lowered his trousers to moon an audience whilst onstage at the ChillOut Festival in Daylesford, Victoria, in March 2022.

[86] Shortly before 8 pm on 11 October 1984, while Meldrum was in London to tape interviews with David Bowie, Boy George and Billy Idol, a fire broke out in a hallway closet at his Richmond residence.