[SiBurning]

If anyone else is thinking of it, I just did it the hard way...

There's a small circuit board onto which the headphone and input jacks are attached. It's below the large board . The 2 boards are attached by 2 pins which go through plastic spacers that separate the boards. Holding the player open with the usb port towards you, just above the display, from the right, there are 3 square things then a 6 pin chip. After that are 2 pins that are soldered to the board here, and also soldered below the other board. If you desolder these pins from the large board, you should be able to (very) gently (please) pry the large board apart from the small one. Then you can unscrew the small board from the case. The rest of the disassembly is easy. Just pry apart gently.

Picture it like this: once you get the whole assembly apart and put the 2 boards back together, you can resolder the pins from the outsides of both boards. The trouble is getting the boards out of the case, since the little board is screwed down to the case.

Hopefully this will help anyone else thinking of modding it. I ended up just snapping the main board off, breaking the solder connections at the pins. Trouble is, now only one channel makes it to the headphone jack. Hopefully, it's not a fatal mistake, and it's only busted at the output stage.

Tip #1: cover your workshop floor with a smooth flooring surface such as linoleum or marble, and keep it clean, just in case you pop off a smd capacitor. Good luck finding one in a carpet or between the boards of a wooden floor. I can't find anything missing, but I heard something tiny fall out.

Today's soldering lesson for me is smd doesn't like normal size desoldering braid, and a 10x jeweler's loupe isn't enough for more than 10 minutes worth of smd work.

 

[kennethsf]

Hey! How did you manage to pry open the cover?

I mean, I removed the 4 screws, then ran my fingernails (so as to not cause marks on the plastic case) across both sides to no avail.

Looking more carefully, I found that there are two small tabs towards the in/out connectors, which are reachable by lifting the gray plastic cover a little (it is affixed with adhesive paper) Sadly, when pressing over one of the tabs it moved "a little too much" so I decided not to continue until I had more info.

I guess the case opens from the USB connector side while maintaining the in/out side attached while it is done. (as in raising a laptop's screen)

Would it be too much to ask if you post a small photo of one of the two covers as seen from the inside so I can see where all the plastic joints are?

The player came with a slightly damaged joystick (looks like a common issue) and it's a lot easier for me to repair it than to return it.

Besides, it's just interesting to be able to trace a schematic of the audio output stage to find where we can make some improvements

 

[SiBurning]

Quote:

Originally Posted by kennethsf Hey! How did you manage to pry open the cover? I mean, I removed the 4 screws, then ran my fingernails (so as to not cause marks on the plastic case) across both sides to no avail. Looking more carefully, I found that there are two small tabs towards the in/out connectors, which are reachable by lifting the gray plastic cover a little (it is affixed with adhesive paper) Sadly, when pressing over one of the tabs it moved "a little too much" so I decided not to continue until I had more info. I guess the case opens from the USB connector side while maintaining the in/out side attached while it is done. (as in raising a laptop's screen) Would it be too much to ask if you post a small photo of one of the two covers as seen from the inside so I can see where all the plastic joints are? The player came with a slightly damaged joystick (looks like a common issue) and it's a lot easier for me to repair it than to return it. Besides, it's just interesting to be able to trace a schematic of the audio output stage to find where we can make some improvements

This is the best I can do for now.
http://home.nyc.rr.com/stevieo/iFP-790.plastic.jpg
http://home.nyc.rr.com/stevieo/iFP-790.tabs.jpg
http://home.nyc.rr.com/stevieo/iFP-790.casefit.jpg

iFP-790.tabs.jpg shows 3 tabs on the top plate (in front) on the side of the lock slider (forward in picture), two on the pushbutton side. The main case body has two delicate connectors at the headphone jack end that attaches to the front plate. These tabs have a hole in them, but they must be there just to add flexibility to the tabs--nothing fits into them. These tabs snap over a ledge on the front plate--you can see the bit of red. I removed the end cap (the little piece at right in the picture with the jack holes) by gently pulling it straight out. It has a piece jutting out (at back of the end cap in the picture) that looks like two piece of plastic that attaches to a hole in the body underneath the screw tube. Finally, the pushbutton part has two tabs that fit into holes in the body. The hole tabs on the body that accept the pushbutton piece are as delicate as the tabs on the end cap side of the body. Be gentle.

Once you get the case opened, you need to get the board out. Don't pry it. First you need to separate those two pin connectors from the main circuit board by desoldering & wicking. Hopefully, you end up with a working board, but I really can't say for sure. This could be a plated through hole that grounds both channels.

Once you get the pins desoldered, the main circuit board can be pried out gently. The 2 pins you desoldered are fitted with plastic sleeves that hold the circuit boards apart at the right distance, and they offer some slight resistance to prying. There's also a multi-pin snap-on type connector (no snap or catches though, it just slides in & out) attaching the main circuit board to the small one. On the other end of the main circuit board is the spring end (negative terminal) of the battery contact. This slides out from the case easily. When you want to slide the circuit board out, the contact points at the edges of the circuit board and the case body are all easily visible.

Once you get the main circuit board out, unscrew the smaller board (2 or 3 screws) and pry gently--this board is connected to the positive terminal of the battery connector, which is a metal plate that fits snugly into the body.

I didn't comment further in the original post because most of the parts can be pried out gently without much trouble. Of course, your mileage (and touch) may vary. As usual with these things, you do sometimes need to wedge some contacts apart while separating the others. Just be very gentle when using any tools. It all comes apart rather easily with a light, but firm and steady touch, but a tiny slip or any but the minimal pressure can easily break those little tabs.

 

[zcream]

An old thread, but I'm wondering if someone has ever tried to mod the internal iriver ifp-series pre-amp ? 
I love the form factor of the iriver recorders, and wanted to see if I could replace some parts and improve the mic pre-amp noise ?