Chosen Solution
Hello, i recently get Panasonic RQ-SQ20 and try to restore it. This is what i done so far: When i try to power it up, i don’t get a red light indicator so i try to disassemble the device. Then i desolder the board from the chassis and battery connector just fell off. I solder it back, try to power it up and still nothing. Next, i inspect the board and found it had battery leak corrosion around IC4. Then i try to scrub the board with flux and little bit of solder and some of the copper pad fell off. I tried to connect the broken pad with thin copper wire but still not working. Here what i know so far: Main GND and VCC is getting around 1V. What should i try next? I have a schematics but can’t really understand it properly. PS: I’m doing this as a hobby and not fully know what i’m doing.
Schematics Board Table [Update 12/12/21]
@catzymbs something does not look right with the solder bridge on C601, which could go to R602 but the orientation at the point of your jumper looks off as well as the location of the bridge. Let me see if we can clear the schematic up a bit. I hate that they have both sides on one page. I attached some images just for reference of what those parts are and how they are connected. There is nothing missing between R601 and R701 but it could use a bit of cleaning up. Lets see what we find around that area. I also flipped the image of the underside so that it would match your image. that was done for clarification only. You mentioned “corrosion around IC4” that area looks good. Was that a typo?
@oldturkey03 My bridge to C602 is trying to emulate SL but i think it is not necessary and i’m removing it now. Then black stuff at the IC6 left is my attempt to put solder so i can connect broken via. Yes “corrosion around IC4” is a typo, sorry about that.
Because i can’t follow the PCB trace properly, i try to shine a phone camera light diffused by few layer of paper towel to the PCB. From my previous attempt i know that via under my wire bridge is destroyed so i try to connect it with long copper wire but still not working. I suspect that there is a further corrosion under the IC6 and unfortunately further procedure require IC6 desolder and i don’t have right equipment to do so. But thanks for y’all help so far.
Generally, battery corrosion occurs around the battery. Battery corrosion is best removed with vinegar. I am suspecting the corrosion may be due to spilled liquid as in Coke or other such liquid since it appears to be away from the battery contacts. If so, the damage could be extensive and may affect components as well as traces.
