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PotatoFi

Macintosh Classic II Restoration

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This is a great looking system.  Good job!!  I am in the process of restoring a classic ii as well.  I am recapping the analog board, and when i was replacing CP5, i was removing the huge glob of hot glue that was covering it and the ceramic cap next to it... i accidentally mangled the ceramic cap.... i need to replace it, but can not figure out what size i need.  I was able to read the markings from it, but not sure about the voltage, as it seems it doesn't have the voltage on there. the markings are " B - 682K - (Manufacturers symbol) 28 "

 

I take it its a 6800 pico farad rating, 10% fault tolerance.  There is a line under the 682K, which i have read means 50V or 100V... not sure about that though.

 

by the way, it is CP21 on the board.  I just need to know what to replace it with.  I'll probably be using digi-key to order the parts.

 

Any help would be greatly appreciated!  Thanks.

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6 hours ago, Dkopsieker said:

This is a great looking system.  Good job!!

Thank you so much!

6 hours ago, Dkopsieker said:

by the way, it is CP21 on the board.  I just need to know what to replace it with.  I'll probably be using digi-key to order the parts.

I popped the case off and took a look, and sadly, I don't think I'm going to be able to help very much. Mine says "682k" on one side, and absolutely nothing on the other. :( Sorry that I can't be more helpful here!

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Hi PotatoFi,

 

Nice job!  I have a bunch of yellowed stuff and I looked up peroxide and retrobrite from reading your thread and noticed you used 3 bottles of 40 hair developer.  My wife has 20 and she said to use very little of it.  I took my 3rd yellowest keyboard and put a little of the 20 in the cap and spread just a tiny bit with a q-tip and wrapped it in plastic and put it in the sun this morning for 2 hours. Since it was a test I wasn't even careful about how I put it on with the q-tip and I thought I'd get a nice marbled effect if I crinkled up the plastic wrap. But, except for the spot I missed with the q-tip it seems to have worked anyway. No marbling.

 

I left the space key alone so it would be easier to tell how it worked since my iPhone 5 will look different at different times of the day.

 

Before I started.

 

IMG-1029.jpg

 

how it looked with the developer spread. You can see I barely, barely used any:

 

IMG-1030.jpg

 

 

how it looks now that I am done after loosely, crinkley, wrapping it and leaving it in the sun for two hours. Then put back together.

 

IMG-1033.jpg

 

 

you can still see a faint streak of yellow on the top right of the keyboard where I missed a spot (bottom right of the photo) and as I said I left the space bar alone for color comparison.

 

My question is since you used a lot more and a lot stronger hair developer and haven't had a yellow reoccurrence, did you use less before and had it return to yellow?  I'd like to use as little as possible but without having the yellow return (I'll be keeping them away from UV and heat going forward).

 

Here is what I used (and used hardly any of it) it's called Clairol Pure White and is $2.85 for a 16 ounce bottle.

 

IMG-1032.jpg

 

 

Thanks. And again, nice job!

 

Eric

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Looks good! I can't tell whether you popped your Apple logo out or not... be sure to do that! I've had the red and yellow parts turn white when leaving them in the sun with hydrogen peroxide.

 

The recurrence of yellowing has been extremely slight on my Macintosh SE FDHD that I did in December. I did that one with 30 Proof cream under a UV lamp in our utility room. Despite the very slight recurrence... I think the retrobrite was completely, totally worth it.

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