A while back I bought 3 little MP3 players from BGmicro ($5 each), and final got around to cracking open one, fortunately with minimal damage to the case. These things are about the size of usb jumpdrive.
I soldered couple of wires to the play switch, and made an opening in the case for the wires. Soldering was like micro surgery, everything is SMD and super tiny. I had to do it looking through a magnifer, and my iron tip blocked the view, but got it done. Plugged in the power, still works, wire leads work in place of button.
I then opened the battery compartment half, soldered some leads to replace the battery.
Now for the fun part...
To start the player, need to hold the button for about 1 second. I need to do this when I power up the unit. Will turn it off by dropping power (well actually when the NiMH batteries run out).
Plan on using 6 cells for 7.2 volts to run a LM386 amp, the MP3, and whatever control circuit needed. Figure an LM317 will be good enough to drop the 7.2 volts down to 1.5v for the MP3 player, the amp should work off anything over 4 volts.
When I apply power to the MP3 player, I need close a switch for atleast one second to start playing, unfortunately I was unable to follow the traces from the switch, so no telling what's going on. Need something like a relay to do the job. Was wondering if there is something simpler than using a 555 monostable circuit. Just seems like a little much for something that will only be needed for one second each time the power is applied.
I soldered couple of wires to the play switch, and made an opening in the case for the wires. Soldering was like micro surgery, everything is SMD and super tiny. I had to do it looking through a magnifer, and my iron tip blocked the view, but got it done. Plugged in the power, still works, wire leads work in place of button.
I then opened the battery compartment half, soldered some leads to replace the battery.
Now for the fun part...
To start the player, need to hold the button for about 1 second. I need to do this when I power up the unit. Will turn it off by dropping power (well actually when the NiMH batteries run out).
Plan on using 6 cells for 7.2 volts to run a LM386 amp, the MP3, and whatever control circuit needed. Figure an LM317 will be good enough to drop the 7.2 volts down to 1.5v for the MP3 player, the amp should work off anything over 4 volts.
When I apply power to the MP3 player, I need close a switch for atleast one second to start playing, unfortunately I was unable to follow the traces from the switch, so no telling what's going on. Need something like a relay to do the job. Was wondering if there is something simpler than using a 555 monostable circuit. Just seems like a little much for something that will only be needed for one second each time the power is applied.
