Complex sentence: Dudley Harwood, the BBC engineer instrumental in the creation of the 3/5A, started Harbeth and obtained a license in 1977, but the company produced no LS3/5As for a decade.
Split into simpler sentences: Dudley Harwood, the BBC engineer instrumental in the creation of the 3/5A, starts Harbeth. Although licensed since 1977, the company produced no LS3/5A for a decade.