Ronald writes –
The term “mixed-signal” is usually reserved for circuits and ICs that process both analog and digital signals. In that sense the title “A mixed-signal LED clock” is perhaps misleading since this is a digital clock from beginning to end. However, the readout is analog and since the beast had to be given a name, I a called it my “mixed-signal” clock.
Somewhere in the middle of the eighties, when I was studying, I joined the ECA: the Eindhoven Computer Association, a microcomputer club in Eindhoven. Although I am not a member anymore, they still exist and have now been active for more than 25 years . Being situated in Eindhoven, the club obviously had close links with Philips, and regularly obtained surplus supplies of components of various kinds. I remember that these components could be bought for fl 0.10 (10 guider cents) a piece on every Tuesday evening. At one time they had a batch of LEDs in various shapes and colors. In those days a LED was not quite the common component it is today. The availability of these LEDs in these beautiful colors and nice shapes suggested the idea for a clock with an analog clock face…
A “mixed-signal” LED clock (source and schematics included) – Link.