Build (46) DDL01 Hex NOR boards. This will include soldering around 7,000 components, so allow yourself at least a few weeks for this task. Make sure you have enough solder on hand, and try not to inhale too much flux smoke.
Build and test the (4) power supply boards as detailed in the build logs.
Build and test the spread-spectrum exciter board as detailed in the build log.
Build and test the (3) display boards.
Build and test the (6) diode-ROM 7-segment encoder boards.
Assemble the seconds-counter stack with point-to-point wiring according the schematic. Be sure to test as-you-go, because finding wiring errors after the entire module is assembled will be much more difficult.
Assemble the minutes-counter stack; this is identical to the seconds-counter.
Assemble and test the hours-counter stack using point-to-point wiring according to the schematics. Note that this module differs from the other two counters.
Assemble and test the segment driver and encoder stack according to the schematic. Ensure that each digit is displayed correctly before proceeding.
Connect the three counters and the segment driver module to complete the clock