I have an MP3 player that I really like, they are not made any longer. What is good about it is the ergonomics and user interface which is designed to be used by tactile feedback while the thing is in your pocket, not the capacity.
Over the past years it has started to get a poor connection with the 3.5 mm TRS audio jack. I would twist it a few times, add moisture, and it would be good enough to use it for a while. Finally I had enough and thought I'd try fix this myself. The device has two such 3.5 mm audio jacks (one for audio in, one for audio out), I never use the audio in, so I would swap the two, and use the "good one" for audio out.
I assume that most or everything that I'm doing is wrong and can damage the components in some way or do some other harm, so don't do this yourself if there are anyone on this forum that knows less about this than I do. So this is what happens when a beginner tries to fix his own MP3 player. I set my soldering iron to 320 degrees centigrade and get to work.
Problem 1:
The TRS components are soldered firmly in three separate places. How do I remove it? I cannot just put the soldering iron to one solder spot and pry it off, it is too firmly kept in place by the two remaining solder points.
My solution:
Remove as much solder as I can from all of them, then heat up one point and carefully pry it away from the PCB at that heated point. Repeat and rinse for each of the points.
Problem 2:
My solution to problem 1 resulted in a torn trace leading up to one of the TRS components, of course this happened on the side that I need to use for audio out, so this must be fixed.
Problem 2:
Fix the torn trace.
My solution:
I use a scalpel to grind down to the copper under the solder mask. I use a very fine wire I harvested from some unrelated component to solder onto the now shorter and exposed copper on the torn trace. The other end is soldered directly to the TRS component. I check for continuity and it checks out OK.
Problem 3:
The picture above was taken before the final adjustment to this, and doing this final adjustment I managed to remove the adjacent small resistor. Then I discovered that during my procedure to remove the TRS components in the first place I had managed to knock off two other resistors!
The following three resistors outlined in red needed to be replaced (notice that one of them is in place in this picture, but it also needed to be put back in place).
My solution to problem 3:
I have no idea how to do this, nor do I probably have the equipment for it. I imagine I destroyed the resistors using this "procedure" that I thought of myself.
These resistors are so tiny they are hard to even pick up. I prepare the solder spots on the PCB (excuse my terminology) with small globs of solder. I "attach" one end of the resistor to the soldering iron, push the other end gently into one of the solder spots on the PCB. At this point it is so hot that it melts that little glob of solder and "sticks" to that spot. The other end is then gently brought down into the other "solder spot". Since it melts both ends I found that it thankfully sticks more readily to these spots than to the soldering tip, hence it "lets go" of the soldering iron by itself using this procedure.
The end result:
Does it work? No.
Still disassembled but given power it powers up, seems to work, but there is no audio whatsoever.
I measured the resistance in the resistors while still attached, they are all the same, 0,7 ohms I believe. But note that this is measured while they are still attached to the PCB, which I believe gives inaccurate results? It was hard getting them in place so I would like to avoid taking them off again just to measure.
How should I proceed from here? Have I destroyed these resistors? I have an inexpensive digital oscilloscope and some other basic tools.
What did I do wrong in getting this far? How am I supposed to get those resistors back in place without doing it the way I did?
Over the past years it has started to get a poor connection with the 3.5 mm TRS audio jack. I would twist it a few times, add moisture, and it would be good enough to use it for a while. Finally I had enough and thought I'd try fix this myself. The device has two such 3.5 mm audio jacks (one for audio in, one for audio out), I never use the audio in, so I would swap the two, and use the "good one" for audio out.
I assume that most or everything that I'm doing is wrong and can damage the components in some way or do some other harm, so don't do this yourself if there are anyone on this forum that knows less about this than I do. So this is what happens when a beginner tries to fix his own MP3 player. I set my soldering iron to 320 degrees centigrade and get to work.
Problem 1:
The TRS components are soldered firmly in three separate places. How do I remove it? I cannot just put the soldering iron to one solder spot and pry it off, it is too firmly kept in place by the two remaining solder points.
My solution:
Remove as much solder as I can from all of them, then heat up one point and carefully pry it away from the PCB at that heated point. Repeat and rinse for each of the points.
Problem 2:
My solution to problem 1 resulted in a torn trace leading up to one of the TRS components, of course this happened on the side that I need to use for audio out, so this must be fixed.
Problem 2:
Fix the torn trace.
My solution:
I use a scalpel to grind down to the copper under the solder mask. I use a very fine wire I harvested from some unrelated component to solder onto the now shorter and exposed copper on the torn trace. The other end is soldered directly to the TRS component. I check for continuity and it checks out OK.
Problem 3:
The picture above was taken before the final adjustment to this, and doing this final adjustment I managed to remove the adjacent small resistor. Then I discovered that during my procedure to remove the TRS components in the first place I had managed to knock off two other resistors!
The following three resistors outlined in red needed to be replaced (notice that one of them is in place in this picture, but it also needed to be put back in place).
My solution to problem 3:
I have no idea how to do this, nor do I probably have the equipment for it. I imagine I destroyed the resistors using this "procedure" that I thought of myself.
These resistors are so tiny they are hard to even pick up. I prepare the solder spots on the PCB (excuse my terminology) with small globs of solder. I "attach" one end of the resistor to the soldering iron, push the other end gently into one of the solder spots on the PCB. At this point it is so hot that it melts that little glob of solder and "sticks" to that spot. The other end is then gently brought down into the other "solder spot". Since it melts both ends I found that it thankfully sticks more readily to these spots than to the soldering tip, hence it "lets go" of the soldering iron by itself using this procedure.
The end result:
Does it work? No.
Still disassembled but given power it powers up, seems to work, but there is no audio whatsoever.
I measured the resistance in the resistors while still attached, they are all the same, 0,7 ohms I believe. But note that this is measured while they are still attached to the PCB, which I believe gives inaccurate results? It was hard getting them in place so I would like to avoid taking them off again just to measure.
How should I proceed from here? Have I destroyed these resistors? I have an inexpensive digital oscilloscope and some other basic tools.
What did I do wrong in getting this far? How am I supposed to get those resistors back in place without doing it the way I did?
