Go Back   VEX Forum > Community > Technical Discussion

Technical Discussion Open Technical Discussion of the VEX Robotics System.

Reply
 
Thread Tools
  #1  
Old 03-15-2012, 01:54 AM
Quazar's Avatar
Quazar Quazar is offline
Senior Member
 
Join Date: Aug 2007
Location: SF Bay Area
Posts: 1,240
Images: 16
Good Audio Amp board

The "SP" speaker port on the Cortex comes up from time-to-time. There are lots of little utility-board amps on the market that will work, but most of them are bulky and require >5V to run. So you need some additional power source (or a Y-cable on your main battery).

Well, last Friday, Sparkfun Electronics introduced a tiny $8 amplifier board that runs on 5V and will work with the Cortex SP port. You just provide the cable (cut one end of a spare extension cable) and a basic 8Ω speaker (nearly any salvaged speaker will do).

I hooked it up and it sounded great. I wanted it really loud, though (if my robot is making noise, I want it to get attention!). The board has a pair resistors you can change to increase the gain, and with some experimentation, I found that 47KΩ resistors make it loud without significant distortion.

Name:  SFE-BOB-11044.jpg
Views: 570
Size:  31.5 KB

Here is a picture of my setup. You can use some of the disused velcro circles from the VEXnet keys to hold it and a small speaker to a bit of Vex metal for easy mounting.

If folks are interested, I can post a few more details on how to wire this board up.

Cheers,
- Dean
Reply With Quote
  #2  
Old 03-15-2012, 09:08 AM
Rswsmay's Avatar
Rswsmay Rswsmay is offline
Senior Member
 
Join Date: Aug 2005
Location: Lithonia, GA
Posts: 165
Re: Good Audio Amp board

I would definately be interested in hooking up one of these to my test bed robot.
Reply With Quote
  #3  
Old 03-15-2012, 12:14 PM
Quazar's Avatar
Quazar Quazar is offline
Senior Member
 
Join Date: Aug 2007
Location: SF Bay Area
Posts: 1,240
Images: 16
Re: Good Audio Amp board

I just put a diagram in the gallery to help folks set this up:



Cheers,
- Dean
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 03:05 AM.


VEX and VEX Robotics are trademarks or service marks of Innovation First International, Inc.
Copyright © 2002-2013. All Rights Reserved. VEX Robotics, Inc. is a subsidiary of Innovation First International, Inc.
All other product names/marks of others are the property of their respective owners.