The Certina 29-151 watch movement, used from 1972 onwards, shares some similarities with the 7802A but specific differences are unknown. Key features of the 7804A include an electronically controlled balance motor, a sweep second hand, a day function that can be quickset by repeated pushing of the crown with the 12-hour position at the bottom, supporting two languages. Furthermore, it presents a quickset date function that can be adjusted by repeatedly pushing the crown with the 12-hour position at the top. The movement also includes a hack feature.