Dfplayer loud 38 Hz noise with all power supplies?
anonymous 2016-10-12 20:17:53 3114 Views3 Replies I have a Dfplayer mini mp3 player that I have used for a while in a robot connected to 3W speakers. Recently it started to make a loud low frequency noise when playing files. The noise is around 38Hz. I noticed from scope measurements that the noise frequency is observable in the supply voltage as a ~.2V dip for 3ms occurring every 26ms.
('0', 'dfplayer on creeper 40Hz noise2.PNG')
The Dfplayer is causing the power supply dip because the noise is the same with multiple power supplies. I also noticed the player is not responding to the mp3_set_volume command, I think it is full loud. Do I have a damaged device? Can anyone recommend troubleshooting steps?
Thanks,
Stephen
('0', 'dfplayer on creeper 40Hz noise2.PNG')
The Dfplayer is causing the power supply dip because the noise is the same with multiple power supplies. I also noticed the player is not responding to the mp3_set_volume command, I think it is full loud. Do I have a damaged device? Can anyone recommend troubleshooting steps?
Thanks,
Stephen
dfplayer on creeper 40Hz noise2.PNG Download(0) 2018-08-18 09:24:46 Hi, I have the very same problem. Has this been resolved or a solution/ work around found for it.
It's not the power supply to the board. Scope trace shows 4.5V rock solid.
Any help from DFRobot on this would be VERY MUCH appreciated.
Gary
garystofer
It's not the power supply to the board. Scope trace shows 4.5V rock solid.
Any help from DFRobot on this would be VERY MUCH appreciated.
Gary
garystofer 2016-10-20 23:07:15 I have tried a separate 5V power supply and had the same noise problem. I had the ground of the separate power supply connected to the ground of the Arduino, I assumed this was necessary. The volume is still at maximum loudness no matter what volume number I set, 0 to 30. Is the 40Hz frequency of the noise significant? Does this indicate a particular problem or source of the noise? Thanks. 
anonymous
anonymous 2016-10-20 02:50:25 Hi Sir,
About the noise problem, maybe you can read the FAQ-Q1 at the bottom of our wiki. And you said the mp3_set_volume command is not responding, when you set the volume to zero, there will be a voice? Wendy.Hu
About the noise problem, maybe you can read the FAQ-Q1 at the bottom of our wiki. And you said the mp3_set_volume command is not responding, when you set the volume to zero, there will be a voice?
Wendy.Hu 