The C3jr board can now be finished off by soldering in all the 5mm LED's.
PWR and DBG LED : Install these two indicator LEDs first. The power LED on whenever the clock is plugged in. This can be rather annoying. I don't install this LED. The short lead (Cathode) of the LED always goes toward the label.
Install the rest of the LED's for the array. The short lead (Cathode) of the LED always goes toward the label.
This can go very smoothly and quickly. I've found the fastest way to install the field of LEDs is in two steps: even numbered rows and odd numbered rows. This allows ample space for the soldering iron and gets the job done in short order. See picture below with the first set of rows complete.
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