DIY MP3 Radio

[edouble101 314]

I want to give my brother a unique gift for his birthday. I decided that I am going to make him a MP3 radio. It will not produce ear shattering audiophile output but it should sound good for what it is. The design of this radio will make it useful for near field listening such as a computer desk or small room book shelf.

There will be four different audio input methods:

• MP3 decoder with memory card and USB drive reader
  
• Bluetooth input capability
  
• 3.5mm audio input jack input
  

The unit will have three identical enclosures. The center enclosure for the electronics and two enclosures for the left and right speaker. I am using a Dayton audio 15x2 amplifier and Tang Band 3" full range drivers. I will not be using any filters on the drivers. I will be porting the speaker enclosures so a baffle step filter should not be needed. Someday when I have the dough for a proper microphone and software I will be able to design filtering networks.

My MP3 decoder is on backorder. When I have it I will post pics.

I have not started assembly this yet. I am still piecing everything together and figuring it out.

I am using an outboard power supply.

The Bluetooth module and MP3 decoder need 5V. I will be building a 5V regulator.

I placed a penny in the pics so you can see how small this guy is

[An-i-no 86]

Sounds neat. Way more technical than anything ill ever do.

[edouble101 314]

Sounds neat. Way more technical than anything ill ever do.

Actually it isn't that technical. I am just wiring up a bunch of electronic components.

It probably will not be the best sounding radio but it will be unique!

[Sencheezy 689]

Woah! Thoz Tang Bangs are rated @ 13014590 watts

[S.DeYoung 967]

Looks like a cool idea. Keep us posted on updates!

[lithium 358]

cool project!

[edouble101 314]

Small update:

*Sorry for the shitty pics.*

I used a Radio Shack breadboard to layout a simple 5V regulator circuit built around a LM7805.

LM7805 diagram

Here is the basic circuit.

Board design

Simple video of how the circuit works. For some reason the video quality became very poor when uploading it

Next up is to transfer the circuit to a PCB(printed circuit board).

[edouble101 314]

Received my MP3 decoder today

Added a penny in the pic to show size

[ssh 924]

Looks nice, should be pretty sweet when it's all done.

I read you want to get a mic so you can make networks, can't you design and test them out with software?

[edouble101 314]

Looks nice, should be pretty sweet when it's all done.

I read you want to get a mic so you can make networks, can't you design and test them out with software?

Yes you can, primitively.

Play incremental test tones and use a spreadsheet to record the SPL. The data that was collect will represent any peaks and dips in the FR.

[edouble101 314]

Here is a screenshot of the PCB layout that I designed, very basic. I need to print this out and transfer it to a single sided copper board to be etched.

[duanebrow 6]

Very cool. I love it!

[edouble101 314]

Very cool. I love it!

Thanks Duane. I am anxious to hear this radio!

[CrownVic 15]

I love tinkering around with stuff like this.

Cool project, did you find an instruction manual for this or is your design?

[chainsaw 5]

This is a cool build, I can't wait to see the finished product

[edouble101 314]

I love tinkering around with stuff like this.

Cool project, did you find an instruction manual for this or is your design?

No instruction manual or how to. There are similar projects around the net but nothing exactly like this.

This is a cool build, I can't wait to see the finished product

I just got my copper boards in the mail. After I make the PCB I can continue. I have until April to finish this so no rush.

[edouble101 314]

Update.I finally had a minute to mess around with this.

I revised my circuit layout with thicker traces and larger solder through holes.

I printed my layout on Press-n-Peel. I trimmed and piece of copper PCB board to size.

I iron on the Press-n-Peel. Here is what is left on the copper board.

I etched the remaining copper off the board.

After cleaning off the toner, copper traces remain!

Up next is to drill the through holes and solder the components.

Edited February 12, 2012 by edouble101

[An-i-no 86]

Honestly...that is cool as hell.

I'd probably end up like

[edouble101 314]

Honestly...that is cool as hell.

I'd probably end up like

Thanks man

I had imagined the copper traces be more fine lined and precise. But I guess for a first time PCB construction it isn't too bad. Good enough for this atleast.

Edited February 12, 2012 by edouble101

[chainsaw 5]

Edub, I know you got a while before you give it away, but I am loving this build and dying to see how it all comes together in the end. Are you gonna make some sort of housing for everything? Like a hobby box,etc?

[edouble101 314]

Edub, I know you got a while before you give it away, but I am loving this build and dying to see how it all comes together in the end. Are you gonna make some sort of housing for everything? Like a hobby box,etc?

I will be fabricating three enclosures. One for each speaker and one for the electronics. The enclosures will be a mostly 3/4" oak with a dark stain. I also have a couple unique materials/components I will be using

[edouble101 314]

I have the PCB done. Onto bigger and better things!

Drilling the through holes

All soldered.

Penny to show size.

Edited February 13, 2012 by edouble101

[Shogen 325]

crazy tiny!!!

[edouble101 314]

crazy tiny!!!

Yep.

I drew up the enclosure plans last night. Possibly next week I will start on them.

Edited February 17, 2012 by edouble101

[TRP 42]

Done with it yet?