The circuit descriptions as well as how you build and use the clock can be found here in the user manual
Schematics:
Schematic 1 – Power Supply
Schematic 2 – CPU
Schematic 3 – 60hz Ring CounterSchematic 4 – 6hz Ring CounterSchematic 5 – 1 Sec. Ring CounterSchematic 6 – 10 Sec. Ring CounterSchematic 7 – 1 Min. Ring Counter
Schematic 8 – 10 Min. Ring CounterSchematic 8 – 1 Hour Ring Counter