68kMLA Classic Interface

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Is this SE dead or do i repair it ?
Posted by: Marsupilami on 2018-07-16 00:49:10 Hi, I have found a SE 1/40. But after opening it, what a mess ! The battery exploded and the acid (or whatever it is) spread over a large area. Once cleaned with soapy water and an old toothbrush, many electronic components were damaged. Do you think I'm trying a repair? Or do i keep it for spare parts ? Is it possible to find the affected components at Farnell or elsewhere? Who would have the references (I don't know anything about electronic but I know how to weld). As you see it it is necessary to change the yellow chip ("Filter") but also the resistors (R1), the black component on the top (near CR1) and the very small yellow thing (C1 or C10/C5) also. And while I'm at it, we'll have to do a full recap too. Thanks
Posted by: bibilit on 2018-07-16 01:01:27 You can have a try, had one like that and managed to clean it and worked fine afterwards. But chances are thin on the ground, i have had many of those "bomb" related boards, only repaired this particular one, rest was dead.
Posted by: Bolle on 2018-07-16 01:37:42 Looks like it is repairable from the pictures so far. Remove the filter network, the SCC and the one line drivers that shows corrosion on its legs to see how it looks underneath them and if the traces going to them are still fine. If everything looks ok from there on I would proceed with replacing parts that look sketchy.
Posted by: BadGoldEagle on 2018-07-16 09:47:47 It should be repairable. When I got my 1/40 a year ago, the board looked pretty much the same albeit looking somehow better. It seems that all 1/40s were equipped with Maxells. Every single one I've seen for sale has issues. Go figure. Here are a couple pictures of my unit... I didn't report back since May of last year since there was no real breakthrough. There are only a couple bad traces on my board, I patched one and it somewhat works now. I knew this alone wouldn't fix it but I fired it up anyway. It won't go past the happy mac as there are still some bad traces I didn't patch (I didn't have my iron with me at the time...). But still, that's promising. I know Uniserver had found a reliable source of compatible bourns filters (that's the yellow chip near the battery). I should order some and you too before that source runs out.
Posted by: zezba9000 on 2018-07-19 01:35:42 My Classic had some battery damage. Washed it in baking soda first. Scrubbed with toothbrush in soup water after. That fixed my major issues. Might try that.
Posted by: tanaquil on 2018-07-19 09:43:17 Scrubbed with toothbrush in soup water after. I sincerely hope that is a typo for "soap and water"... (Though, would you want to use soap on a motherboard? I guess some people use dish soap, I generally avoid it.)
Posted by: techknight on 2018-07-21 14:31:39 well looking at the cleaned up pictures, there is at least a half a dozen vias that have been eaten away.
Posted by: Marsupilami on 2018-07-24 06:16:35 Thanks a lot for your answers, i'll give it a try 🙂 I found the bourn filter here https://www.digikey.fr/scripts/DkSearch/dksus.dll?Detail&amp;itemSeq=267314554&amp;uq=636680161845531637 and the caps here : https://www.digikey.fr/scripts/DkSearch/dksus.dll?Detail&amp;itemSeq=267314857&amp;uq=636680161845541639 BUT...i need your help before ordering, what are : This resistor (R1) : When you are color blinded (like i am) it's not easy 🙂 The black component on the top (near CR1) The very small yellow thing (C1 or C10/C5) also. Thanks
Posted by: Marsupilami on 2018-07-27 08:01:34 UP... Are the very small yellow thing (C1 or C10/C5) caps ? but wich ones ?
Posted by: zezba9000 on 2018-07-27 22:36:41 I sincerely hope that is a typo for "soap and water"... (Though, would you want to use soap on a motherboard? I guess some people use dish soap, I generally avoid it.) lol, ya type. It worked well. I also used baking soda first as I thought it would neutralize acid on the board.
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