I had planned to replace the inadequately designed power supply for the clock, and I had figured out how to update the signals to the relay coils, but I had really hoped that I could avoid re-wiring all of the individual connections between the relay contacts and the display bulbs (10 + 6 + 10 + 6 + 10 + 2 of them). I had figured out the connections and how they could be used with the new power supply without having to completely rewire them.
In 1973 I was using some of the latest technology, including “ribbon cable”, an evolutionary step from a tied cable bundle. Individual wires were laid side-by-side and cast in place with an insulating plastic bond. They were also called flat cables. Once again, my source of this unusual wiring system was from my dad’s ham radio shack.
I found them particularly appealing because they were color-coded with the series used to identify resistor values- black, brown, red, orange, yellow, green, blue, violet, gray, white to represent digits 0, 1, 2, … 9. They include the colors of the rainbow, and I recall thinking how nice they will look in the finished clock, which motivated me as I connected them to the stepper relays.Continue reading