Hanna-Barbera was the first cartoon production studio to cease using Douglass's services. They first used the laugh track for their prime-time shows, such as "The Flintstones", "Top Cat", and "The Jetsons". They then expanded using the laugh track into their daytime fare, starting with "The Banana Splits" in 1968, which emulated Filmation's "The Archies". Successful series prior to 1971, like "Scooby-Doo, Where Are You!", "Harlem Globetrotters" and "Josie and the Pussycats" employed a full laugh track. This changed at the start of the 1971–72 season, when Hanna-Barbera employed their limited laugh track using the MacKenzie Repeater machine, a tape machine that can play up to five sound effects repeatedly on rotation, which cued up to five Douglass laughs repeatedly. Mixed with a metallic sound, it included three mild laughs and two uncontrollable belly-laughs (one contains a woman laughing prominently at the tail end). With the exception of their variety shows, such as "The Hanna-Barbera Happy Hour", which they briefly turned to Douglass for sweetening, Hanna-Barbera used these laughs regularly over the next decade on nearly all of their Saturday morning fare.