Overview Amateur Radio Operators (aka HAM Radio) use 24 hour UTC (Universal Coordinated Time) for much of their operation. I decided to build a digital clock using the low-cost TM1637 4 digit displays and a Raspberry Pi Zero W instead of just a GUI clock. (Hardware is fun!) The TM1637 driven display has four 7 segment leds with a center colon “:” between two sets of digits. It requires two wires to drive the display plus 5V + and Ground for a total of 4 wires. For this particular project, I wanted the Raspi to get its time from NTP…