Show Posts
Pages: [1] 2 3 ... 6
1  Using Arduino / General Electronics / Re: LED current limit resistor on: April 06, 2013, 07:44:13 pm
Will the ports burn out if I connect them to another device without a resistor? lets say a guitar pedal effect.
The port is connected straight to the effect and it works fine, but if I use a resistor bigger than 30 ohms the effect pedal would not work, so I decided to take it out.
2  Using Arduino / General Electronics / LED current limit resistor on: April 04, 2013, 08:30:12 am
I wonder if I can eliminate the resistors by using the PWM at low values.
Thanks
3  Using Arduino / Microcontrollers / Re: Arduino Pro Mini C106 Cap on: December 18, 2012, 07:12:11 pm
Thanks, I will replace the other capacitor in the other arduinos and see if I can make them work as well. smiley-grin
4  Using Arduino / Microcontrollers / Re: Arduino Pro Mini C106 Cap on: December 18, 2012, 02:57:17 pm
I do not know why the last arduino blew because I used a 9v batt, everything was fine except that I connected the common to GND next to VCC, I replaced the cap and it worked.
I always use a regulated source 9V or 12V, but the problem with the other burned arduinos was the polarity of the source.
Quote
author=retrolefty link=topic=138058.msg1036980#msg1036980 date=1355849946]
That cap would appear to be C19 in the schematic posted in the product page:

http://arduino.cc/en/uploads/Main/Arduino-Pro-Mini-schematic.pdf

If you are finding this cap to fail multiple times on multiple boards, you are most likely subjecting it to too high a raw voltage. The product page list +12vdc to be the maximum voltage to apply to the raw pin. If you apply higher then the maximum rated voltage for the cap (not sure what it's voltage rating is) that could account for your multiple failures. What kind of voltage source are you using to feed the raw input? Is it a regulated voltage or a unregulated source?

Lefty


5  Using Arduino / Microcontrollers / Arduino Pro Mini C106 Cap on: December 18, 2012, 09:14:18 am
Over the past year I blew four arduino pro minis (dummy mistakes), The cap C106 next to RAW PIN seemed to be bad so I replaced it with a regular size cap in one of my burned arduinos and it worked.

I find out that the cap C106 is 10uf
Is the other cap the same value?
I have two discontinued arduinos Pro mini and the numbers are different C104, are those also 10uf?
Thanks.
6  Using Arduino / Programming Questions / Re: Why does PWM creates noise? on: October 23, 2012, 06:16:46 pm
How is this all powered? - you really need to keep the Arduino's supply separate from the LED strips (where all the current switching is), and pay attention to grounding - separate ground wires out to the audio input and the PWM output might make a difference.
I think that's a good idea too, I had the same problem with effect pedals, most of them are connected in my main power supply station but some need to be with their own power supply because they create noise too.
Right now I have the Arduino and the strip running with the same 12V power supply.
7  Using Arduino / Audio / Why does PWM creates noise? on: October 23, 2012, 02:32:32 pm
I'm using just the audio input part of this diagram to A0 so the arduino can read the signal of my guitar and make the led strip blink.http://interface.khm.de/index.php/lab/experiments/arduino-realtime-audio-processing/
But instead of using only one audio jack input I'm using two in parallel to send part of the signal to my amplifier and some to arduino.
The problem is when I switch to a PWM sketch, noise gets to the amplifier and disappear when the value reaches zero.
Thanks.
8  Using Arduino / Programming Questions / Why does PWM creates noise? on: October 23, 2012, 02:10:09 pm
I'm using just the audio input part of this diagram to A0 so the arduino can read the signal of my guitar and make the led strip blink.http://interface.khm.de/index.php/lab/experiments/arduino-realtime-audio-processing/
But instead of using only one audio jack input I'm using two in parallel to send part of the signal to my amplifier and some to arduino.
The problem is when I switch to a PWM sketch, noise gets to the amplifier and disappear when the value reaches zero.
9  Using Arduino / Project Guidance / Re: How can I connect my guitar to analog input? on: June 14, 2012, 10:33:25 pm
Thanks I will try that circuit.
10  Using Arduino / Project Guidance / Re: How can I connect my guitar to analog input? on: June 14, 2012, 10:19:51 pm
Effect pedals like delay, distortion, overdrive, chorus etc.
11  Using Arduino / Project Guidance / How can I connect my guitar to analog input? on: June 14, 2012, 08:32:15 pm
My project consist in connecting my electric guitar to the arduino and make the led strip blink.
Since the electric guitar signal is weak I have it connected to stomp boxes first to boost the signal a little.
I don't think the connection to the arduino is right even though it works when I strum the guitar,
one of the reasons is because the threshold has to be set really low around 10,
and the other one when I switch to fading mode using PWM a buzzing sound comes out from my amp,
I think I'm creating a ground loop connecting the guitar this way.
So the connection is like this:
The positive side of the jack goes to A0 and the negative side to GND and I have a 1Mohm resistor in parallel (the connection idea was taken from the nocksensor project) http://www.arduino.cc/en/Tutorial/KnockSensor
12  Using Arduino / Programming Questions / Re: Read this before posting a programming question ... on: May 25, 2012, 12:55:32 pm
Nice.
13  Using Arduino / General Electronics / Piezo element reading problems on: March 27, 2012, 09:34:22 am
Hey guys, I'm having problems trying to read a piezo element, it does the job when I tap it with my finger but I need a little more sensitivity.
The piezo is connected to A0 and grown with a 1Mohm resistor in parallel.http://www.sparkfun.com/products/10293
The threshold has to be around 30, and I would like to know if I can amplify the signal a little bit to have a better reading with out damaging Arduino's input.
Thanks.
14  Using Arduino / Programming Questions / How can I post an Image? on: March 19, 2012, 04:00:20 pm
I can't post the image from Eagle.
15  Using Arduino / LEDs and Multiplexing / Re: Power supply question. on: December 01, 2011, 06:52:46 pm
Ok, I'll try that
thanks.
Pages: [1] 2 3 ... 6