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That is very strange. The link still works fine for me.

Thanks pcamen. That's what I was thinking, but I wanted a second opinion just to make sure.

I am currently repairing a Mac Classic II that I picked up a few weeks ago and I have found a capacitor that appears to be burned on the bottom of the logic board. Of course, I need to replace the cap (C39), but the schematic for the logic board shows a weird symbol after stating the value of...

Unfortunately, there is not. Five or six of the pins are broken off entirely and several of the pads on the motherboard have been completely eaten away by the corrosion.

Really? If that is that case, then it would be really cool if someone could program a microcontroller to emulate the PRAM chip.

Darn. I guess I won't be able to get the Quadra working after all because replacement RTC/PRAM chips seem to be pretty much impossible to find.. Thanks for all of the help!

I am certain that the SCSI drive has a compatible OS on it because it is running System 7.5. According to my research, U92 is the RTC and PRAM chip, so that shouldn't have anything to do with the SCSI bus, right? It is a relief that the green tint is probably not a problem with the computer...

I tried desoldering and resoldering U92, even though it is missing some pins, and to my amazement this caused the computer to boot to the blinking floppy disk screen. It will boot just fine from floppy, but I now have two more problems. 1. The screen has a greenish tint to it. What is causing...

I have now replaced all of the parts that were missing, with the exception of C61, which I have not ordered yet, and U92, which is only hanging onto the board by only a few pins. I now get a startup chime when I turn the computer on and the reset and interrupt buttons seem to work fine. However...

Thank you for the pictures! I agree that it appears to say IA5. I believe this means that it is a 0.1uf capacitor.

Can you tell me the code on capacitor C61? I can read all of the numbers on all of the components except for that one. 

Thank you! That is perfect!

Thank you for the picture! Unfortunately, I can't make out the values of those parts, so those additional photos would be great!

Can someone upload some pictures of the area of the board near the reset and interrupt switches? I am trying to order replacement parts and I want to make sure that the component values are what I think they are. There don't seem to be any pictures of that area in the link that tattar8 provided...

Thank you for this advice. I will try to resolder the parts that fell off and I hope that my RAM chips aren't bad.

Thanks! I will look into that.

Do you know the values of the components that I listed above? They disintegrated when I was cleaning the board so I don't know what to replace them with.

I recently bought a Macintosh Quadra 700 off of eBay (https://www.ebay.com/itm/Vintage-Apple-Macintosh-Quadra-700-M5920-Desktop-Computer-w-Harddrive-Mac-iMac/273781054522?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649) and it has some corrosion on the logic board from a leaky...

Sorry for the late reply, but I checked the resistor network the way that you described and it seems to be fine. I don't know what the problem is at this point. Do you think that I should just give up on it?

How would I go about testing that part? What does it do exactly?