A Mixed-Signal LED Clock

Posted on Feb 6, 2014

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

A Mixed-Signal LED Clock
Click here to download the full size of the above Circuit.

. 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 [1]. 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. Normally, I never bother about making a printed circuit board for my circuits. I prefer working on these cheap prefabricated pertinax breadboard cards. However, for the circular face of my LED clock I had no other alternative than to etch a PCB (Fig. 1). I made it in the summer of 1987, and after I had placed the LEDs and finished the wiring, I put it into a drawer. There it was forgotten due to more pressing projects (girls and examinations). Two years ago I found it again and decided to finish the clock. It actually became my first PIC processor project. The circuit of the clock contains no real surprises. A (literally) striking feature about this...

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    Minimal metal detector
    Pseudorandom Simulated Flicker Sequencer
    High-Output Pulsed-Tone/Light-Activated Alarm Circuit
    Flash Signal Alarm Circuit
    Water Level Controller
    Big vacuum tube tesla coil with GU-81M
    Arduino Runing On && Charging NiMH batteries
    vehicle tracking system using gps
    am-fm-sw active antenna
    GM Silverado: 2003 Chevy Silverado K1500 Ext Cab 5.3l V8 DTC
    Icom IC-751 RAM reprogramming
    Measuring the differential pressure sensing bridge circuit diagram
    Multi-point circuit diagram of a remote control switch
    DC exciter excitation mode circuit