Simplify the following text for a Grade 5 native English-speaking person.
Original: One of the earliest pay-per-view systems on cable , the Optical Systems Channel 100 , first entered service in 1972 in San Diego through Mission Cable ( acquired by Cox Communications ) and TheaterVisioN , which operated out of Sarasota , Florida .
Simplified: One of the first pay-per-view systems on cable was the Optical Systems . It was first used in 1972 in San Diego .