Raspberry Pi - Pandora Player
Haven't worked on this in awhile because I didn't understand certain concepts. I have purchased the Arduino Starter Kit to help teach me some important things that will be useful in completing this project.
The idea for this project came from two different projects I ran across while browsing instructables.com. Pandora's Box is a project that turns a Raspberry Pi in to a simple Pandora music player without an internal speaker and RaspbAIRy is a simple AirPlay speaker with an additional audio input. I liked the idea of having a Pandora music player with a built in speaker so that it can be self contained without any wires (except power) coming out of it.
I picked up this cool looking Webster Electric TeleTalk desktop intercom box from a thrift shop for $15. It was complete but the internal tubes and components had long since gone out. Since the internals were burned out, I went ahead and removed them. After removing the internals I took that lovely aluminum mesh faceplate off to try and clean it up.
This box housed a 3" speaker with 4" mounting holes. That posed a small problem since those two numbers don't really go together in the audio world anymore. I bought a 3.5" speaker to fill the gap with the hope that it would fit the 4" mounting pattern. It didn't. Went to the store and bought a Dremel with a circular router jig and a sheet of acrylic and went to town (My poor neighbors). Before long my apartment smelled like a nail salon but I had a nice speaker adapter to mount my new speaker to my old TeleTalk!
Speaker - Vifa TG9FD-10-04 from Parts-Express.com
I worried over button placement quite a bit so I sat down, dug out some graphing paper, and drew the internal layout of the case so I could have a firm grasp on where I couldn't place the buttons. In the end I decided to place the buttons two inches from the front edge. I determined this would not interfere with the speaker mounting or the function of the speaker and still grant enough room for the wires that will provide the signal from the push button switches.
I managed to find some super tiny push buttons that I could also get decorative nuts for. Instead of having a traditional hexagonal nut, these are a nice rounded kind that give a more refined look.
Push Buttons - Grayhill 30-3 from OnlineComponents.com
Decorative Nut - Grayhill 30C1023-1 from OnlineComponents.com
LCD and Volume Knob
This is how (and where) the LCD will be mounted. My next step after making the cut out in the box was to make a similar sized cut in the anodized aluminum mesh face plate. I made the hole in the face plate slightly larger than the LCD to have extra space for the speaker cloth to pass through. In the end, I learned to respect jewelry makers because cutting down that aluminum face plate was a painstaking process. It turned out well so I am more than pleased with it.
For volume control I bought a 10k ohm potentiometer and re-used one of the TeleTalk's original knobs. I drilled a hole in the side of the box for the volume knob.
LCD - LCD-09068 from SparkFun.com
Potentiometer - Bourns 3852A-282-103AL from AlliedElec.com
Since the face plate on the TeleTalk had some smoke damage I decided to cover it with dark red speaker cloth. I figured it would match well with the dark brown wood and the TeleTalk logo. The picture is the first attempt at affixing the cloth to the metal. On this one I used simple double sided scotch tape to see how it would turn out. May switch to some heavier duty 3M carpet tape or something else strong but low profile.
Speaker Cloth - Burgundy speaker cloth from SpeakerWorks.com
I bought this 10 watt mono power amplifier kit to drive the speaker on this project. As everyone knows headphone jacks do not provide enough power to move a speaker so you must amplify the audio to a point that can make the driver move. The first picture is showing how the kit came and the second picture is the end result after spending time with my soldering iron. This kit came with everything except for the terminal blocks so keep that in mind when purchasing, both are linked below.
Audio Amplifier - Class AB 10W Mono Power Amplifier Kit TDA2030 from Parts-Express.com
Terminal Jacks - Altech Corp. 30.202 from AlliedElec.com