A problem often encountered by Virtual Boy users are glitchy displays, leading to horizontal lines, reversed or generally distorted images, or even complete loss of display activity.
All those symptoms are usually caused by the ribbon cables connecting the LEDs to the motherboard becoming loose, or peeling away from the display PCB.
Fixing your Diplay: Oven method
DogP has come up with a way to fix the problem by opening the system up, removing the display, sticking it in the oven to re-melt the adhesive, and reassemble. It’s not a difficult procedure, except that the typical security bit can’t get to the deepest screws on the VB, so you either need a special screwdiver, a modified bit, or a modified screwdriver.
You can find a guide to fix your displays on DogP’s Project:VB.
Fixing your Diplay: Bypass method
Another way has been proposed by DanB. To permanently fix the problem, his idea was to replace the loosening ribbon cables with some better wires, which he soldered to the PCB. This solution requires much more skill, though, and should only be performed by solder experienced people with a steady hand and a huge portion of patience.
The complete guide can be found here.
Fixing your Diplay: New methods (RECOMMENDED)
Some more methods have recently been developed by DogP to permanently fix the cable problem (contrary to the probably non-permanent oven method): Thread.
I finally got around to printing a replacement cable chunk… AND IT WORKED! The reason for this was a fellow forum member attempted the solder repair, but damaged the end of the cable beyond repair. Earlier in this thread I posted that I designed a near 1:1 copy of the cable, which is what I used for this. It certainly wasn’t as easy as repairing it correctly in the first place… but wasn’t too bad, and worked first try. Sorry, I didn’t really take pictures along the way, but I think you can kinda get the idea from the pics. Here’s a rundown of the process.
I printed the chunk of cable that I wanted (on Pyralux), etched it, and then tinned it (to keep the copper from oxidizing). I then cut the existing cable back behind the damaged area, exposed the copper, and then soldered that to the newly etched cable. This is where I almost messed up. I wasn’t really paying attention and when I started to solder, I had my iron set to 700F (normal soldering temp). The VB cables shrivel and melt at high temperatures, so on the end I started on, I had to heat it and use tweezers and pull the individual traces back in line after a few of them began to curl inward. Then I bumped my soldering iron down just below 600F and finished soldering the cable without issue (the cable still kinda melts at 600F, but if you’re quick, it’s fine). Because of the lower temp, and trying to minimize the heat to the cable, the solder job doesn’t look great… but it works, which is more imporant than looks. 😉
Then I verified continuity between the new and old half, and made sure there were no shorts (visibly, under the microscope, as well as electrically, with the multimeter). Once I was happy with that, I put a piece of Kapton tape on both sides of the cable to protect and reinforce the newly spliced cable. Then I put a small piece of carpet tape (very thin double-sided tape) on the display PCB and aligned then stuck the cable to it. Then it was just a matter of soldering the new half of cable to the display, which was easy (Pyralux is far less heat sensitive than the OEM cable). Once I did that, I again verified a good connection, and then wrapped that in a thin strip of Kapton tape to make sure it doesn’t peel away from the display and cause stress on the solder joints. After that, it was just a matter of hooking it up and testing. 🙂
Yes, I could have printed an entire cable, but I chose to reuse the good part of the cable for several reasons. The part that goes in the LIF socket should really have a finish other than bare copper… and simply tinned with solder isn’t very good for that either. It also needs a stiffener (that thin piece of plastic attached to the cable that makes it easy to insert/remove), which I probably would have taken from the original cable. Also, the cable at the display PCB end would have been upsidedown from how I wanted it, since my cable is single sided (bare copper would have been facing down, meaning the copper wouldn’t be exposed for soldering, and it’d be easy to short out pins if you don’t have it perfectly aligned).
We’ve also talked about getting new cables professionally made (here: http://imall.iteadstudio.com/open-pcb/pcb-prototyping/2layer-flexible-printed-circuits-fpc-10cm-x-10cm-max.html ). I sent my design to verify that they could manufacture it, and I didn’t hear back, and shortly after, it changed to “Back Order”, and has been for several months. Not sure if that means they’re done offering that service, or if they will actually resume sometime in the future. Most of those places are probably still closed for Chinese New Year, but maybe we’ll know more in a week or two.
DogP
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OK, so I finally decided to attempt the soldering fix on one of my VBs, and there’s good news and bad news-
The good news is that it seemed to go smoothly and the glitchyness that used to be there is now gone. The bad news is that appears to be a new problem- at a certain screen brightness, the position of the screen image is shifted vertically. For bright games like Mario Clash & WarioLand it works fine, but for dimmer games like Teleroboxer and Vertical Force, part of the lower screen is on the top. Does anyone know what could be causing this? It happens equally on both displays. Hopefully I didn’t ruin anything.
I’ll try swapping the displays with my other VB to see what happens.
