Matthew Beckler's Home Page

Home :: Blog :: General :: Software :: Hardware :: Microcontrollers :: Artsy

---

PJRC MP3 Player

Sophomore year of high school in my Digital Electronics class Graham Motzing and I built a hard drive based MP3 player from the kit offered at the PJRC website http://www.pjrc.com/tech/mp3/

UPDATE: I have since taken this project apart, because of difficulties with the lid-mounted switches (problems with shorts and such). I also don't have room for this large of a dedicated mp3 player. I have since used the power switch and power supply in my new lab bench power supply.

Here are some pictures I took of the finished project:

	This is the enclosure I made for my MP3 player. My uncle gave me this box filled with Armor All car care supplies, even though I didn't have a car at the time, so I donated the cleaning stuff to my dad, and used the box for something cooler. I also had a pair of USB speakers, but the USB cable developed a short somewhere in the USB part of the cable. The amplifier and speakers worked just fine with the standard line-in,so I took them apart and put them in the box. I de-soldered the volume knob and the power toggle, and placed them in the lid. I found a short headphone-style cable and connected the mp3 player to the amplifier.
	The white cable on the left is the power from the wall-wart to the speaker amplifier, and that is just a standard ATX PC power supply on the right side, which powers the player, and the standard 3.5" hard drive.
	This is a detailed (and annotated) view of the controls on top. As you can see,the wood that the top was made of liked to split and chip off as I was cutting.
	In this picture you can see the underside of the controls and speakers, as well as the power supply, the amplifier board, the PJRC board, and the hard drive. The two wires that got cut off were supposed to go to a power-indicating LED, but I had a really hard time mounting the LED in the top.
	An even more detailed view of the underside of the controls.
	Here you can see where I attached the wires leading to the top switches, and how I modified the ATX power supply to work with the board, and a manual switch in the top.
	I used some erector set pieces to hold down the power supply, the amplifier, and the mp3 board.
	Here you can see how I attached the hard drive to the inside of the box. You can't see it in the picture, but I glued some foam to the box where the hard drive rests, to cut down on the amount of vibration that is transmitted to the box. You can also see where I soldered the power switch to the pins of the ATX power connector so that I could start the power supply without a computer.

---

Copyright © 2004 - 2024, Matthew L. Beckler, CC BY-SA 3.0
Last modified: 2023-01-09 03:28:29 PM (EST)