Michael Parkin: Gallery owner who championed Whistler and the Chelsea artists and was Radio Caroline's first managing director

Michael Parkin in 1993 with his daughter Sophie, left, and his first wife, the writer and artist Molly (Rex Features)

Michael Parkin was a jovial and generous man who staunchly upheld the civilised principle that business should never be allowed to spoil fun. This only enhanced his success as a gallery owner, managing director of the first pirate radio station, Radio Caroline, the first general manager of Channel Television and a documentary film-maker who won prizes at the Cannes and Venice film festivals. "We must get you a drink, my dear," was a customary greeting, no matter what the hour, "'a little reassurance'."

It was typical of his cavalier spirit – he aspired to the standards of his favourite fictional character, Toad of Toad Hall – that two of his life-changing decisions were taken on the spur of the moment. The position at Channel Television in Jersey caught his eye crumpling up a newspaper to make an early- morning fire for his first wife, Molly Parkin, the artist and writer; he was working a night shift at the Imperial Milk Factory on Harrow Road as well as a day job in Oxford. Since he had experience working at Rediffusion, the ITV company, he seized the moment: "I knew my rivals would apply by post so I caught the first available aeroplane."

The next occasion was in 1972 when, driving past Halkin Arcade in Belgravia, he saw a gallery space for sale. He had been a modest collector for 20 years but with no thought of art dealing, let alone starting a gallery. He made an offer and launched Michael Parkin Gallery, later of Motcomb Street SW1, which closed after 25 years and 218 exhibitions in 1998.

Michael Robert Parkin was born in Putney in 1931; his father owned a haulage company. His parents divorced and at eight he was bedridden for a year with polio. He was a precocious talent on the clarinet and as a Mill Hill schoolboy accompanied Benjamin Britten and Peter Pears in concert. National Service with the Royal Irish Fusiliers was followed by Magdalen College, Oxford, where he read law.

His success at Channel Television saw him head-hunted to front the managerial side of Radio Caroline in 1964: a consortium had been formed by the 23-year-old Ronan O'Rahilly, "the most grown-up young man I've ever known," as Parkin said. His first appointments were two former public schoolboys, Cyril Henty-Dodd, or Simon Dee, and Tony Blackburn – "a nice boy." The enterprise was an immediate success, enabling Parkin, when he left, to fund his own film company and then his gallery.

Parkin caught the art bug when his Aunt Dorothy Clewes, the author, took him to a wartime exhibition where he saw his first Whistler. A love of Whistler and the bohemian Chelsea he embodied became a lifelong passion. As a gallery owner Parkin took advice from fellow dealers in modern English art, especially Godfrey Pilkington and the young Anthony d'Offay, but the military strategy of using a map and red stickers to pinpoint his targets, the whereabouts of every well-known artist's widow, was his own idea. It soon paid dividends, leading to discoveries, cross-references and restored reputations, not least those of Claude Flight and the inter-war Grosvenor School of lino-cut artists. He believed that behind every work of art there was a story, and he took pride in well-researched and designed catalogues. His exhibitions were designed for art lovers, not investors.

His loyalty to Whistler and Chelsea – where he lived and was a stalwart of Whistler's Chelsea Arts Club for 50 years – made his inaugural exhibition an inevitable tribute: "Four for Whistler", the master along with his principal pupils, Sickert, Menpes and the Greaves brothers. It was followed by "The Wonderful Village – Chelsea 100 Years Ago". "The Café Royalists", partly exhibited in the restaurant itself, celebrated its Edwardian heyday as an artistic rendezvous; for the accompanying dinner the owner, Charles Forte, provided 23 bottles of pre-1914 absinthe from the cellars.

People said this event could never be surpassed, so the following year he put together what he always considered his best exhibition, "Fitzrovia and the Road to the York Minster", centring on the legendary Gaullist "French pub" run by his friend, Gaston Berlemont. His second wife, the artist, Diana Head, with whom he enjoyed a long and happy marriage, and his second daughter Sophie, from his first marriage, both curated shows; Chelsea, including such outposts as St Ives, Dieppe and Tangier, was always the core of the enterprise.

There were also two regular events: Parkin's love of cats was celebrated each Christmas with a show by the eccentric cat-painter Louis Wain (1860-1939) and, because of a shared interest in British art from 1890-40, there was an annual collaboration with Hull University Art Collection, originating in his visit to an exhibition by Claude Flight's mistress, Edith Lawrence. Dr Malcolm Easton, the curator, dreaded breaking the news to the old and frail artist that she had not sold a single picture. "You can tell her," said Parkin, "that I am buying the whole exhibition."

Parkin gave up the gallery, but not the business, in 1998, making his and Diana's principal residence a wing of Gunton Hall, north Norfolk. Increasingly ill in recent years, he was lovingly nursed by his family and died peacefully at home.

JOHN McEWEN

Michael Robert Parkin, gallery owner, film-maker, television and radio executive: born Putney, London 1 December 1931; married 1957 Molly Noyle Thomas (divorced 1962; two daughters), 1983 Diana Head (one daughter); died 4 August 2014.