Arduino Nipkow disk clock

There is an old-fashioned type of Persistence-Of-View display called Nipkow disk display. I made a desk clock using that principle.

joekutz

Quantity		Component name
1	×	Arduino Uno
1	×	90LED-strip
10	×	Resistors 10kohm and 100Ohm
3	×	BC547 Transistor
1	×	I2C RTC module I used a MOD-RTC and cannot recommend it :(
1	×	12V fan motor
1	×	8-12V Power supply
6	×	pushbuttons