A PCB design for a wall clock.
This is a circuit and PCB design that uses small LEDs tubes as segments for the clock digits. It's a simple device, driven by an Arduino Nano (including Sketch .INO) that does not connect to a remote data source, does not have a Wifi GUI for set-up, and it does not even persist its time setting, nor does it use a Real-time clock unit or offer an alarm function.
All these shortcomings are of course potential expansions for the future. For now I just wanted to toy around with the bunch of LED tubes I got from AliExpress and see if I can fill the segments with epoxy to make them beefier and shine nicely uniformly. The epoxy is transparent, but I use some droplets of white and yellow epoxy dye to make it slightly opaque.
The clock plugs into a 5V 2A power source (like most USB phone chargers) so indirectly it connects to a wall socket. Setting the time is done by use of 4 momentary push-buttons. The body casing of the clok is made from black foam board (like architects use for maquettes). A piece of clear acrylic can be used to cover the digits.
Ferrie J Bank, Amsterdam 11 September 2021
https://github.com/oudesnepelaar
transistors: C189428 (LCSC.com) 1W NPN 0.6A 40V SOT-223 Bipolar Transistors - BJT ROHS capacitors: C15850 (10 uF) C307348 (100 nF) C29823 (4.7 uF) shift register: C161627 (MC14094BDR2G 3-state outputs, 8 bits shift register) pinheaders 15F (Nano): C124408 switches: C669810 resistors: C23140 (33 Ohm) C17714 (47 Ohm) C4275 (75 Ohm)