After the war, he worked for several radio stations, hosting the popular Irish Hour on WVOM in Brookline, which focused on sports, especially hockey.
The experimental telecast was wildly popular, and later during the 1963/1964 season, Fred hosted the Sunday morning rebroadcasts of edited CBC Television tapes of Saturday night Bruins games in Montreal and Toronto; they were flown back overnight with the team, then seen first at 9 am on WMUR-TV in Manchester, New Hampshire, and WTEV-TV (now WLNE-TV) in the Providence/New Bedford market (the signal[s] of which covered some of the Boston areas), and then at 1 pm on the old WHDH-TV (now WCVB-TV) in Boston, WWLP-TV in Springfield, and WRLP-TV in Northampton.
Fred's telecasts were enormously popular, and within a few years, games would be shown live on WKBG and later began a long run at WSBK-TV.
In 1971, Cusick returned to TV, succeeding Don Earle, who had been hired by WSBK when they began covering the Boston Bruins, as play-by-play man for Bruins' games on WSBK with Peirson as his color man; when NESN was formed in 1984, he did double duty for 11 years, calling games for both channels, first with Johnny Peirson and later both Derek Sanderson and Dave Shea.
He was inducted into the Hockey Hall of Fame in the first wave of media honorees in 1984, and in that year was also named the first winner of the Foster Hewitt Memorial Award (along with Danny Gallivan, Rene Lecavalier and Hewitt himself), "in recognition of members of the radio and television industry who made outstanding contributions to their profession and the game during their career in hockey broadcasting."
In 2007, he returned to the broadcast booth as the Cape Cod Baseball League game of the week play-by-play announcer on WBZ (AM) Radio.