The Berlin Clock (Mengenlehreclock or Berlin Uhr) is a clock that tells the time using a series of illuminated coloured blocks, as you can see in the picture for this project.
The top lamp blinks to show seconds- it is illuminated on even seconds and off on odd seconds.
The next two rows represent hours. The upper row represents 5 hour blocks and is made up of 4 red lamps. The lower row represents 1 hour blocks and is also made up of 4 red lamps.
The final two rows represent the minutes. The upper row represents 5 minute blocks, and is made up of 11 lamps- every third lamp is red, the rest are yellow. The bottom row represents 1 minute blocks, and is made up of 4 yellow lamps.