I made a digital clock using only mechanical relays.No ICs no transistors.
Clock divider divides the 50Hz pulse from the power line and makes 1Hz.
Then the counter counts seconds minutes and hours.Also the 7seg led decoder is made by relays, too.I used 140 DPDT relays,about 300 diodes,lots of capacitors and resistors,and 20meters of copper wire.
