Johnson started to operate a single turntable and speaker sound system in 1968 and started the Special I sound system in 1972, changing the name to Black Scorpio after the name caused friction in the area in which it was based, with the largely People's National Party-supporting locals suspecting sympathies with the Jamaica Labour Party due to its similarity to that party's slogan.

[2][3][4] Other deejays who worked on the system included Culture Lee, Shukashine, Barry Bak, and Lady G.[2] Black Scorpio expanded into a record label in the early 1980s with a studio on Molynes Road in the Drewsland area of Kingston.

[5][6] Johnson had his first hit as producer in 1982 with "Pink Eye" by DJ Sassafrass, the pair having a bigger hit in 1985 with "Pocomania Jump", and Black Scorpio went on to become one of the top labels of the early era of ragga.

[3][5] Black Scorpio productions include recordings by Bunny Rugs, Dennis Brown (More), Gregory Isaacs (Consequence), Frankie Paul (True, Start of a Romance), Garnett Silk, King Kong, Mafia & Fluxy, Papa San (Style and Fashion), Capleton, Bounty killer, Pliers, Mega Banton, Barrington Levy, Beenie Man, and Luciano (Serve Jah).

[3] In 2010, Johnson was inducted into the International Reggae and World Music Awards (IRAWMA) Hall of Fame.