Solder 100nF cap and 680 ohm resistor on the bottom of each rowBoB. The resistor label indicates 470 ohms. We have found in testing that 680 ohms makes a better display and guarantees that the LEDs are never overdriven. Putting these parts on the bottom leaves a nice clean finish.
There are three holes for the resistor. Use the outer two.
Dimming Potentiometer (pot), 2k ohm
GOTCHA! The the top rowBoB has the reverse orientation as the bottom rowBoB.
Solder the first pot on the left edge. On the other rowBoB, solder the pot on the right edge as shown.
The lower rowBoB2 (U2)
The upper rowBoB1 (U1)
Male header pins. Insert the pins long side down into the U1 and U2 sockets. Place the partially completed rowBoB on the pins with the pot. facing the left edge of the board. Solder each rowBoB in place. RowBoB1 goes potentiometer up, rowBoB2 goes pot. down.
Parts 4x 1x12 male header pins