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Got a Color Classic... is this motherboard toast?
Posted by: musicfan77 on 2017-02-08 13:17:58 Took a $20 gamble on a local Color Classic-- owner didn't have keyboard and didn't know if it worked. Had a look at the motherboard and it appears there is significant corrosion near the PRAM battery (but I can't tell if it's from the battery itself or not? I guess the battery was replaced, and velcro'ed onto the board-- is this common?). Basically what I want to know is... is this thing toast, or is there any possibility of its being cleaned/restored? (And, follow up: if it IS toast, who wants to sell me a CC motherboard?) 🙂
Posted by: IlikeTech on 2017-02-08 13:56:12 Why not just do the mystic upgrade with a 575 board. That board looks very dead. IlikeTech
Posted by: musicfan77 on 2017-02-08 14:09:32 Why not just do the mystic upgrade with a 575 board. That board looks very dead. IlikeTech Yeah, I wasn't planning on it, but at this point it would probably be just as much effort. OK, so who wants to sell me a 575 board? 😉 (I know, I will start a thread in the Trading Post)
Posted by: Johnnya101 on 2017-02-08 14:31:51 I don't know... you might have a slim chance... You can always try dishwashing its not like it's gonna hurt it at all.
Posted by: musicfan77 on 2017-02-08 14:58:03 I don't know... you might have a slim chance... You can always try dishwashing its not like it's gonna hurt it at all. I will try that, but I'm pretty sure there are connections that are completely corroded out. Also I can't believe I just now realized there's no RAM in this board! :O I'm an idiot. Guess you get what you pay for!
Posted by: just.in.time on 2017-02-08 15:04:13 The CC board (as well as 520/550/575) has 4MB of ram soldered on
Posted by: musicfan77 on 2017-02-08 15:10:04 The CC board (as well as 520/550/575) has 4MB of ram soldered on Ahhh did not know that. So the slots are just for additional RAM. Cool! Thanks for the info. I've been coveting a CC for a long time so couldn't pass this one up. But clearly I've got more to learn! I tried cleaning it as best I could and figured I'd give it a shot starting the thing up. Didn't work of course, but I did notice that the CRT made a sound when soft powered on. Is this a sign that the PSU and CRT are (possibly) functional?
Posted by: just.in.time on 2017-02-08 15:26:51 Yeah, not much but enough to fire up 7.1 🙂 Shame that the board is in rough shape. I had an extra at one point but sold it to another user here about 6 months ago. Finding a 575 board cheaply may be tricky. However, a left over CC board from someone that upgraded or a 520 board (and to a lesser extent, 550 board) from a destroyed in shipping unit turns up on eBay from time to time for decent prices. As to the monitor making a noise when you flip that main switch, definitely a good sign but not at all a guarantee of functionality. Good luck on your restore 🙂
Posted by: just.in.time on 2017-02-08 15:27:55 For $20 you practically got that thing for free 🙂 I missed that part. Nice find indeed!
Posted by: musicfan77 on 2017-02-08 15:38:18 For $20 you practically got that thing for free 🙂 I missed that part. Nice find indeed! Yeah! Pretty happy about that. Figured it was worth a shot at that price. Thanks again for the info, very helpful!
Posted by: nvdeynde on 2017-02-09 04:48:23 The board doesn't look good, lots of corrosion. I think it's beyond repair. One can always try but it would take a lot of time and chances for success are slim. Don't forget to recap the Analog board of your CC as well as the capacitors are degraded and leaking. Good Luck
Posted by: bibilit on 2017-02-09 05:37:54 Took a $20 gamble on a local Color Classic-- owner didn't have keyboard and didn't know if it worked. Had a look at the motherboard and it appears there is significant corrosion near the PRAM battery (but I can't tell if it's from the battery itself or not? I guess the battery was replaced, and velcro'ed onto the board-- is this common?). I will give it a try, wash the board and clean the area (maybe with vinegar) i have seen worse that worked and better that did not... Yes those 4.5 volt batteries are seen on the last logic boards, earlier one had the usual 3.6 one.
Posted by: LazarusNine on 2017-02-09 10:35:57 In my relatively limited experience, the Colour Classic boards seem uniquely prone to failure with the slightest leakage from caps and/or batteries. I recently had a very slight amount of leakage from a 4.5v battery in my 5400 that may be the culprit for some issues with that logic board. In any case, you can always opt for a 550 board rather than a 575 board in the CC. That's what I replaced my CC board with and it operates really well. It's no Mystic, but then again, at least you can use the Colour Classic's plastic port cover without having to make any changes.
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