Walter joined the BBC in London as a studio manager in 1958. After a year with the BBC in Edinburgh, he moved to Broadcasting House in Belfast, where, after a year, he became a staff announcer. Throughout the 1960s, Walter was the main television news presenter with BBC Northern Ireland. He also looked after the radio continuity operation and presented various radio programmes.
During the 1960s and 1970s, Walter also carried out television continuity duties with BBC Northern Ireland.
In 1978 he went freelance, presenting the magazine programme Day by Day. In the late-1980s, he took up the afternoon slot on BBC Radio Ulster, presenting Love in the Afternoon. He then became the presenter and producer on Love Forty.
In 1998, he was awarded an MBE for his services to broadcasting.