WordClock-2 Assembly Guide 4/20/20 Version 1.3
Page 4
Step 2 – Build the Display Board
All parts are installed on the back of the board (silk screen side) except for the
background lighting LEDs, and the alphanumeric displays.
For ease of assembly, parts should be installed in the order noted here.
•
Install LED11-LED34 (LED11-LED42). Follow the same procedure noted above to install
surface mount parts. The LEDs must be soldered quickly and carefully. Note the
direction. Align the angled corner with the mark on the upper-left corner of the silkscreen.
If an LED must be removed, be careful not to damage the board. The best way to do this
is to cut the LED horizontally with diagonal cutters, exposing the pins. Then lift each pin
to unsolder individually.
•
Install surface mount resistors at R6-R9 (Not Used). The exact value depends on the
color of the display. The correct value is supplied with the displays. These resistors are
used to equalize the brightness between the display and colons. See the bill of materials
for the correct value.
•
Install C11-C14 (C11-C15), the surface mount capacitors, and C15 for the eight-digit
version. They are usually unmarked, tan colored components.
•
Install J5, the 90-degree male connector,
to the back of the display board
. Solder one
pin first, then check the alignment to verify that the pins are parallel to the board.
•
Cut the pin headers to size, and fit them to display LED1-LED6 (LED1-LED8). Each LED
uses a 9-pin header on top, and a 10 pin header on the bottom. Use masking tape to
hold the headers in place. Position the display board upside down on a flat surface, and
solder one pin on each header. Check that the headers are perpendicular to the display
board
and
adjust
if
necessary.
Then
solder
the
remaining
pins.
If individual pins are provided, install them on each display before soldering. Use
masking tape to hold the displays. Then solder all pins.
•
Solder U4-U9 (U4-U10) to the back of the display board. Note the direction.
Pin one is
up on all ICs except U6.
Again, follow the above procedure to install surface mount
