The arms then cause the elements to flip as they count up through the digits. In essence, he engineered a physical decimal to 7 segment decoder, much like the electronic one inside the SN74LS47.

[Fran] demonstrates the display running with a CD4511B BCD-to-7-segment decoder, hooked up with a bunch of 3904 power transistors to get the chip working with filament bulbs instead of LEDs.

This display driver circuit shows how a Seven Segment Display is driving with the help of the 5 stage Johnson decade counter IC CD4033.The IC has counter and decoder in one package. It converts the ...