wire from the cable to the pad as indicated. Continue to
solder the red, orange, yellow, green, blue, violet, gray,
white, and pink cable wires to their respective foil pads.
Twist the ends of the black and tan wires together. Solder
them to the outer foil ast the left of the brown wire as
shown in Figure 9.
As before, at the 9/32 inch hole make a clamp around
the cable using three turns of #14 wire. Glue with GOOP
so that the cable will be secure.
Connecting the D-Sub Connector
and Power supply Wires
Connect the four male D-SUB wires (see Figure 9)
by sweating the wires to the proper circuit board foil. The
wire from D-SUB pin 4 goes to the foil marked 4, etc.
Likewise, connect the female D-SUB wires to the proper
circuit board foil (as also shown in Figure 9).
Photo 6 shows how to position the three-cell AA battery holder. The black negative wire is soldered to the middle connector opposite the spring and the red positive
wire next to it. Use GOOP to glue the battery holder to
the bottom of the box. The AA cells are held in place by a
size 33 rubber band and two blocks of wood (Photo 6).
A 1” x 1/4” x 1/4” piece is glued to a 1.5” x 1/2” x 1/4”
piece of wood as shown in Figure 10. Glue the two wood
pieces to the bottom of the box with the flat side next to
the battery holder. Give the glue 12 hours to cure. After
placing the cells into the battery holder, wrap a size 33
rubber band twice over the battery holder and blocks.
Testing Out the Quiz Box
Turn the front panel over and switch the power to
ON. If the electrical circuit has been constructed correctly,
the POWER LED will start blinking. Make sure the buzzer
switch is ON. Depress the reset push button switch. The
buzzer should sound.
■ FIGURE 10.
If nothing happens, turn the front panel over so you
can check the voltage ( 4. 5 volt) at the three-cell battery
holder terminals. Next, check the voltage at the PCB by
connecting the negative lead from your voltmeter to the
push button switch terminal that is connected to the wire
going to the middle of the board. Connect the positive
voltmeter lead to the power switch terminal coming from
the three-cell power supply. If you get 4. 5 volts, proceed
by making sure the power switch is ON and connect the
positive voltmeter lead to the outside foil of the PCB. If all
checks out but you still don’t get the power LED blinking
or buzzer sounding when you depress the reset switch,
you will need to check all of your solder joints.
Checking the 10 Student Stations
This can be done at the distribution box. Take an RCA
plug apart and temporarily short out the terminals. Replace
the plug handle. With the front panel in place and the
power and buzzer switches ON, proceed to push the
shorted RCA plug into the distribution box jack marked
“1.” LED lamp 1 should light up at the panel, the buzzer
should sound for one second, and the power light stops
blinking for about 10 seconds.
Remove the RCA plug and depress the reset push
button switch. Now move the shorted RCA plug to Jack 2.
LED lamp 2 should light, etc. In this same manner, check
all 10 stations.
With the front panel set in place, use a 5/64” drill to
make pilot holes into the 1/2” x 1/2” wood pieces that
hold the front panel in place. (The front panel is held in
place with five #4 x 3/4” Phillips pan head sheet metal
screws.) Wood screws are okay to use.
■ FIGURE 11.
August 2009 55