Wanduhr

this is a digital 7 segment led wall clock with 42mm high digits based on a atmel atmega168.

the display modules come from RFT, a former manufacturer in the GDR(DDR). (second hand)

it has different modes and can be controlled via the serial (38400) or 'just left running'.

the timer values are determined by experiment and may be slightly different for your crystal

Build Instructions

the atmega uses a 12mhz crystal.

one ULN2003 is used as low-side driver.

a 2-stage bipolar transistor driver is used for the high side for the digits (common anode)

note: you will need to laser the top-left part in wanduhr_holders.dxf twice. (bottom side holders)

if you have open questions about mechanical assembly: check the rest of the pictures at the bottom of the page

Downloads

download source and cad files​