This special timekeeper records individual time periods and adds them together to produce a total time. The circuit uses a real-time clock device, backed up by a ‘Goldcap’ capacitor.When working on a project the time spent in each individual work session often needs to be recorded. Written notes may be made as follows: Period 1: October 7 from 8:13 to 8:55 Period 2: October 7 from 8:56 to 9:32and so on. The differences between the recorded times must be worked out, and then added together to arrive at the total time spent. The device described here was developed to simplify this task. It can keep track of the total time spent on up to nine separate projects. Indeed, it can be used to measure time durations in any application as long as no great precision is required: for example, the duration of a competition, or the operating time of (household) equipment, or the length of an experiment.