untitled

Here’s the rundown of the schematic elements:

The sensor— one of the key components of this circuit — is used to

detect Fluffy jumping on the couch. This vibration/tilt switch sensor

detects motion or vibrations when the switch is mounted with the body

of the sensor horizontal to the bottom of the box. When the sensor

detects motion, it closes a switch, just like how a toggle switch works.

IC1is the other key component of this circuit. This is a chip that you

can use to record a sound or voice message and play it back. We con-

nected the sensor between Pin 24 of IC1 and ground. When the sensor

detects motion and its contacts close, Pin 24 is connected to ground,

which triggers the playback.

S1is a normally open (NO) pushbutton switch that when depressed,

connects Pin 27 of IC1 to ground. This causes the IC to record sounds or

words that you speak into the microphone. Recording stops when you

release the S1 pushbutton.

20

21

14

15

28

12

24

27

19

26

13

17

16

+

MIC

SENSOR

S 1

6V

SPEAKER

C 1

R1

R2 C 2

C 3

R3

IC 1

+

S 2
Figure 14-2:
The
schematic
of the
Couch
Pet-ato
circuit.

Chapter 14: Couch Pet-ato.............................................................................................