Electronics_Projects_For_Dummies
.pdf
200 Part III: Let There Be Light
IC Pin 2 to IC Pin 6
LED terminal block to an open region
Figure 9-10:
Hook up the IC, terminal blocks, and discrete components.
IC Pin 6 to potentiometer terminal block
Potentiometer terminal block to an open region
10.Attach wires from the LED, battery pack snap, on/off switch, and potentiometer to the terminal blocks, as shown in Figure 9-14.
11.Use a mini hacksaw or a utility knife to shape foam blocks so that they fit inside the bottom of the pumpkin, as shown in Figure 9-15.
We used the type of foam used to hold dried flower arrangements. You could also use packing foam.
12.On the side of the plastic pumpkin that will face the talking pumpkin, cut a hole just large enough to allow the LED socket to fit.
13.On the side of the plastic pumpkin that will face away from visitors, cut holes just large enough to allow the shaft of the on/off switch and
potentiometer to pass through.
Be sure to wear safety glasses in case a piece of plastic flies off in the wrong direction!
Chapter 9: Scary Pumpkins 201
LED1 from R1 to ground
R1 from +V to an open region
R5 from Pin 3 of IC1 to LED terminal block
C1 from Pin 2 of IC1 to ground
Figure 9-11:
Insert resistors, capacitors, and an LED on the breadboard.
R3 from Pin 7 of IC1 to potentiometer terminal block
R2 from +V to Pin 7 of IC1
C2 from Pin 5 of IC1 to ground
14.Attach the battery snap connector to the battery pack and place the breadboard in the pumpkin.
Because this pumpkin probably won’t move around much, we just chose to lay the breadboard on the foam, as shown in Figure 9-15.
15.Slip the on/off switch and the potentiometer through the holes you cut for them and use the nuts supplied with them to secure them, as shown in Figure 9-16.
16.Slip the LED socket through the hole you cut for it.
Figure 9-17 shows the LED socket installed in the pumpkin.
202 Part III: Let There Be Light
Figure 9-12:
Solder wires to the on/off switch and the potentiometer.
Figure 9-13:
An LED socket and a socket with LED inserted.
If the hole for the LED socket is small enough that the socket fits tightly, this “press fit” will hold it in place; if the socket is a little loose, use a little glue to secure it to the pumpkin. Read about what kind of glue to use in Chapter 3.
17.Make sure that the on/off switch is in the off position and then attach the battery snap connector to a filled battery pack.
18.Place the battery pack in the pumpkin.
|
|
|
Chapter 9: Scary Pumpkins 203 |
||
|
|
|
|||
|
|
|
|
On/off switch lead |
|
|
Ground LED lead |
Red battery lead |
|
||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Figure 9-14:
Connect wires to the terminal blocks.
+V LED lead |
Potentiometer leads |
Figure 9-15:
The silent pumpkin with the electronics installed.
204 Part III: Let There Be Light
Figure 9-16:
Silent pumpkin with switch and potentiometer installed.
Figure 9-17:
Silent pumpkin with LED socket installed.
Chapter 9: Scary Pumpkins 205
Making a talking pumpkin
This is the mouthpiece of the pumpkin organization: the one that receives the IR beam and plays back whatever you record.
Follow these steps to build your talking pumpkin:
1.Place the voice chip IC and six terminal blocks on the breadboard, as shown in Figure 9-18.
As you can see in this figure, you connect two wires to each terminal block. The wires from these six terminal blocks (TBs) go to the battery pack, on/off switch, record switch, IR detector, speaker, and microphone, respectively.
Figure 9-18:
Place the voice chip IC and six TBs on the breadboard.
2.Insert wires to connect each component and terminal to the ground bus and insert a wire between the two ground buses to connect them, as shown in Figure 9-19.
Figure 9-19:
Connect components to the ground bus.
206 Part III: Let There Be Light
In this figure, seven shorter wires connect components to ground bus (marked with a – on this breadboard); the long wire on the right connects the two ground buses together.
3.Insert wires to connect each component and terminal to the +V bus and insert a wire between the two +V buses to connect them, as shown in Figure 9-20.
In this figure, five wires have been added: four shorter wires connect components to the +V bus (marked with a + on this breadboard); the long wire on the right connects the two +V buses.
Figure 9-20:
Connect components to the +V bus.
4.Insert wires to connect the voice chip IC to the terminal blocks and to the open regions of the breadboard where discrete components will be inserted, as shown in Figure 9-21.
5. Insert discrete components on the breadboard, as shown in Figure 9-22.
The short lead of the LEDs and C2 go to the ground bus.
6.Connect 6" wires (any color will work just fine) to the speaker and solder them, as shown in Figure 9-23.
7.Connect the black wire from the battery pack snap and another 6" black wire to the on/off switch and solder them together, as shown in Figure 9-23.
8.Connect a 6" red wire and a 6" black wire to the microphone pins, as indicated in Figure 9-24. Then solder them, as shown in upcoming Figure 9-25.
9.Connect a 6" red wire and two 6" black wires to the IR detector pins, as indicated in Figure 9-24; then solder them, as shown in upcoming Figure 9-25.
Chapter 9: Scary Pumpkins 207
10.Connect two 10" wires (any color works) to the record switch and solder them, as shown in Figure 9-25.
11.Attach the wires from the battery pack snap connector, on/off switch, IR detector, microphone, and speaker to the terminal blocks, as
shown in Figure 9-26.
When attaching the wires to the terminal blocks, cut the wires to the length you need and strip the ends.
IC Pin 14 to terminal block for speaker
IC Pin 15 to terminal block for speaker
IC Pin 21 to open region of breadboard
IC Pin 23 to terminal block for IR detector
Figure 9-21:
Connect the IC to the TBs and available locations for discrete components.
IC Pin 27 to terminal block for record switch
IC Pin 20 to open region of breadboard
IC Pin 17 to open region of breadboard
Open region of breadboard to terminal block for microphone
208 Part III: Let There Be Light
12.Use your handy mini hacksaw or a utility knife to shape foam blocks to fit inside the bottom of the pumpkin.
13.On the side of the plastic pumpkin that will be out of sight, cut holes just large enough to allow the shaft of the on/off switch, microphone, and record switch to pass through.
14.On the side of the talking pumpkin that will face the silent pumpkin, cut a slot just large enough to allow the IR detector to fit through.
Capacitor C1 and resistor R1 in series between wires to IC Pins 20 and 21
Resistor R4 between +V and an open region of the breadboard
LED2 between resistor R4 and ground
Resistor R2 between IC Pin 19 and ground
LED1 between IC Pin 14 and ground
Figure 9-22:
Insert discrete components on the breadboard.
Capacitor C2 between IC Pin 19 and ground
Resistor R3 between capacitor C3 and +V
Capacitor C3 between microphone terminal block and IC Pin 17
Chapter 9: Scary Pumpkins 209
15.Place the breadboard and speaker on the foam. Then slip the on/off switch, microphone, and IR detector through the holes you cut, as shown in Figure 9-27.
Figure 9-28 shows the IR detector protruding from the side of the pumpkin.
16. Tuck the wires off to the side; refer to Figure 9-27.
You can secure the on/off switch with the nut supplied and use either a press fit or a bit of glue to hold the microphone and IR detector in place.
Figure 9-23:
Wires soldered to speaker and on/off switch.
17.Slip the record switch through the hole you cut for it and secure it with the supplied nut; refer to Figure 9-27.
The direction of the threads on the body of the switch determines which way you insert it. The one we used had threads positioned such that the nut would be attached from inside the pumpkin, as shown from the outside in Figure 9-29.
18.Insert the wires from the record switch to the remaining terminal block on the breadboard.
19.Make sure that the on/off switch is in the off position and attach the battery snap connector to a filled battery pack.
20.Place the battery pack in the pumpkin.
Your pumpkins are all ready to scare the pants off of your Halloween visitors. The completed talking pumpkin is shown in Figure 9-30.