learning the ropes

Shinyoung made a mold and produced a total of 10 static models of Dust to display at the ITP Spring Show.

I also realized that we need a better way to connect the audio output of the Coby MP3 player to the Dust circuit board. For the breadboard, we connected a 1/8″ mini phone plug from the output of the MP3 player into the input of the amplifier section.

I want to remove the headphone jack from the MP3 player for our smaller prototype in order to eliminate the bulky plug.

Time for surgery again.

After poking around for awhile with a multimeter to try to figure out how the jack was wired, I gave up and focused my efforts on freeing the SMD jack from the MP3 player’s board. It was easier to diagnose the wiring of the jack once it was off the boad.

Since I was tired, I soldered the wires on the wrong side of the board at first (wasn’t paying attention to the orientation of the USB pins I soldered on earlier in the day).

In order to reduce the size of the new Dust prototype, I am further hacking apart the Coby MP3 player. I bought an SMD mini USB connector from Digikey to attach to the printed circuit board. My plan is to replace the USB connector on the Coby unit with four male headers which will plug into the main Dust board. It was very confusing to make sense of the USB pinout. The mini connector has 5 pins, but the original large USB connector has four pins.

In the process of coaxing the original USB connector out, I damaged one of the vias and pads on the Coby board. I hope the damage isn’t permanent. You can see the lifted pad right below the “B1″ label (upside down)

I tried to repair the lifted trace and pulled out pad with a short section of wrapping wire.

Notice the wrapping wire soldered onto the end of a male header pin. The next trick is to solder the stripped end of the wrapping wire to the lifted circuit trace. I applied superglue to the bottom of the trace to hold it down and then scraped its surface to expose the copper.

I’ll won’t know if the repair was successful until I get the MP3 player attached to the main Dust circuit board. I’m still a little concerned that the USB wires going between the boards need to be shielded.

I found out last week that the Secret Tree was accepted as part of the Maker Faire in San Matteo, CA. Unfortunately, the notice was a bit too short for us to be able to make the trip.