Sound Switcher

Have you ever had your music cranked up at work and didn't realize someone was trying to talk to you.  Even worse, have you ever wanted to sleep at work, but didn't have a good way to wake up if someone (like your boss) was about to come into your cubicle.  I have.  To solve these problems I invented the Arduino based Sound Switcher.  

Basically this uses 6 transistors to switch between a sound source (in my case an iPod) and Ladyada's Wave shield letting you know what's going on.  You can then connect the Arduino to whatever type of sensor you like.  For example, mine's connected to a Parallax Ping ultrasonic range finder, microphone, doorbell button, and computer (alerts on a new email).  You could go further by connecting a photo resistor to detect when your cell phone is ringing (the screen lights up), or a Parallax CH4 sensor so you can get an early warning of raising methane levels in your cubicle because your cubicle mate had too much cabbage at lunch.  Anyway, most of you probably don't have that problem (wish I didn't).

Besides what the project actually does, it also gives instructions on converting text to a wav file and transfering files to the SD card on the Arduino over Serial.  Hopefully these can be usefull to others in their projects.

NOTE:  I'm pretty new to all this stuff, so there's no guarantee I'm doing things right.  This is the first project I've ever designed with transistors, so I may be missing some caps and diodes somewhere . . . If anyone has any advice I'd be happy to hear it and incorporate it.

Step 1 Parts

1- Arduino
1- Wave Shield (Ladyada)
6 - 2n3904 transistors
6 - 330 Ohm resistors
6 - 22 Ohm resistors
2 - 10k Ohm resistors (pullups for buttons)
2 - buttons
2 - Stereo male headphone connectors
1 - female stereo headphone connector

Whatever sensors you want, I did
1 - Microphone
1 - Parallax Ping Ultrasonic Range Finder
1- Photocell
1 - Computer running a Ruby script that checks email and connect to the Arduino over serial
 

Comments

[Etudahart]

I have some 5 v speakers, but i believe the current flowing through the circuit is too low. how did you get the speakers to be so loud?

[modeemo]

what format is your schematic in?

[makcim]

rename .tmp to pde

[Etudahart]

I want to build one of these that uses an IR sensor to switch from one speaker to another.. But this looks like such an intimidating project to take on. Im not very experienced with constructing such projects. am i going to need a soldering iron for this project as well?

[davewking]

 Well, let's see

Arduino $30
Wave Shield $22
6 Transistors - 60 cents
then probably $1to $2 worth of transistors
I'm guessing the stereo plugs are a couple of dollars a piece, I used parts from broken electronics for mine.

[punkhead58]

What was your budget?