newplumber
Senior Member
Hi
When using the MP3 player with four lm386s...the sound is amazingly clear...when I was testing just using a picaxe/mp3/lm386/speakers...I was able to
kill alot of the amped corrupted noise output from the lm386 by adding a 10 Uf cap as close to the vcc/grd on the mp3 (not lm386) as possible.
Which worked great with almost perfect sound from the sd card ...then when I installed the mp3 player to my clock ...it started picking up the
noise from the pwm apa102 leds...I even unplugged the mp3 and the noise out of the speakers was the same (humming) ...my thought is somehow
the noise is getting to the lm386s ...i have twisted pair power to the lm386s...I was wondering if anyone dealt with a issue like this
I did try covering the circuit in aluminum and to ground with no change
I will get a picture/schematic (probably next week) to show whats going on.
FWIW I have the clock working perfectly with sound by turning off the power to the lm386s
using a mosfet and a picaxe pin and only turning power on when a sound file needs to play
When using the MP3 player with four lm386s...the sound is amazingly clear...when I was testing just using a picaxe/mp3/lm386/speakers...I was able to
kill alot of the amped corrupted noise output from the lm386 by adding a 10 Uf cap as close to the vcc/grd on the mp3 (not lm386) as possible.
Which worked great with almost perfect sound from the sd card ...then when I installed the mp3 player to my clock ...it started picking up the
noise from the pwm apa102 leds...I even unplugged the mp3 and the noise out of the speakers was the same (humming) ...my thought is somehow
the noise is getting to the lm386s ...i have twisted pair power to the lm386s...I was wondering if anyone dealt with a issue like this
I did try covering the circuit in aluminum and to ground with no change
I will get a picture/schematic (probably next week) to show whats going on.
FWIW I have the clock working perfectly with sound by turning off the power to the lm386s
using a mosfet and a picaxe pin and only turning power on when a sound file needs to play