The ultralow-cost, two-digit- counter circuit in Figure 1 represents an attempt to reduce the number of components using a mostly software approach and a low-cost microcontroller, the PIC16F84A. The ...

So he built a mechanical 7-segment display instead! Currently, [Jens]’s channel is in the four-digit subscriber range, so he planned to build a four-digit display.

It’s interesting what you see when you train a black light on everyday objects. We strongly suggest not doing this in a hotel room, but if you shine UV light on, say, a printed circuit board,… ...