Watara Supervision Repair Guide
- No Power On Led
- No Display
- No Sound
- No Ground connection
Supervision was kept in mint condition with no use for almost 15 years. Some days ago I tried to turn it on but it failed with the symptoms stated above. I searched on the net but there exists next to nothing about repairing a supervision unit. So I decided to try on my own.
I assume that anyone who reads this text has a basic understanding of opening up an electronic device, soldering etc, so I wont get into many details about how to open the unit, separate the screen from the main board etc. Moreover the supervision is a pretty simple device, however careful moves are required when dismantling it. So, first of all remove all 6 screws, do not be in a hurry to take apart the plastic case since you have to carefully detach the screen from the main board. They are connected together in the upper side of the unit (the main board is screwed on the back plastic case and the screen well, on the front plastic case), so try not to bent or break any connector. Moreover there is a ribbon cable (seems very fragile) connecting the main board with the gamepad controller. Now all we have to do is to detach the main board from the back plastic case in order to have access to the cartridge connector. This is easy, just remove the screws holding the board on the back case. Picture 1 shows pretty much the situation (note that in this picture the main board is attached again to the screen)
In my case the problem was that for some reason the screen circuitry had no ground connection. According to this article http://blog.kevtris.org/blogfiles/Supervision_Tech.txt the cartridge slot connector should have a pin allowing ground connection. This pin is the upper rightmost pin as we are looking the unit with screen facing down. It is the pin the screwdriver is touching in Picture 1 So all we have to do is to give ground to this pin. Ground can be found at the power supply plug, at the place where the screwdriver touches at Picture 2. Solder some wire to connect the pin with the ground like I did in Picture 3. Note that I did not solder on the cartridge connector’s pin itself but I followed the printed line which leads to a small hole just beneath the 5th and 6th connector pins (Picture 4). But of course it’s ok if you solder on the 1st pin itself. In Picture 5 you can see the black wire soldered to the ground at power supply plug.
That was all, give some power to the unit and if this was the failure reason it should light up. Bear in mind that the unit must have a cartridge in the slot in order to power up. So don’t forget this and think that the unit is still dead.
Cheers to all! Thanks for reading,
eLefas (C) 2012, first published at http://www.pleft.eu/watara