Instructables

Add Sound Effects to your R/C Car

Featured

Step 9: Adding Audio

Picture of Adding Audio
To add the audio circuit, you'll need a few additional parts;
  • Small Speaker
  • LM368 Audio Amp
  • 220uF Electrolytic capacitor
  • 10k ohm potentiometer
  • Screw Terminal connector
  • microSD card to hold samples
The kit includes all the parts for the audio circuit except the speaker and microSD card.  Here's the circuit we'll build;



Start by adding a few jumpers;



there will be seven jumpers, total, and I've marked them with a black line in the photo. 

Add the audio amp (the LM386).  Note the position of the notch on the chip in relation to the board;



Now, add the volume knob;



The middle pin on the knob connects to P4 on the Propeller Platform.  One leg connects to the third pin on the amp, and the other pin connects to ground.

Now, add the big capacitor;



Note the stripe on the Capacitor.  It indicates the negative side, and it should go as shown in the photo.

Finally, add the Audio connector;



Speakers have two leads, one lead goes in each screw terminal connector.  They aren't polarized, so it doesn't matter which lead goes to which terminal.
 
Remove these adsRemove these ads by Signing Up