Trying to recap my LC III and ran into a problem

3 posts / 0 new
Last post
Offline
Last seen: 16 hours 39 min ago
Joined: Jul 14 2018 - 12:54
Posts: 45
Trying to recap my LC III and ran into a problem
AttachmentSize
Image icon Motherboard uncapped4.41 MB
Image icon R1 and R2 pads2.32 MB

So I'm trying to recap my LCIII motherboard.  I managed to remove all of the old capacitors, clean all the pads (all of which survived) but I just noticed that the resisters at R1 and R2 are missing, and one of the pads at R1 seems to have fallen off.  The pads on R2 are still there and I cleaned them as well as the remaining pad at R1.  The board did work before all of this but would take forever to boot.  

 

I don't know how long R1 and R2 have been missing, but I can't imagine that it's a good thing that they are.  The old capacitors clearly leaked but thankfully didn't corrode any of the legs on the ICs.  So do I have a problem?  Can R1 and R2 be repaired?  Do I even need to?

Below are pictures of the board and a closeup of R1 and R2

 

 

Offline
Last seen: 16 hours 39 min ago
Joined: Jul 14 2018 - 12:54
Posts: 45
Update: I was just looking at

Update: I was just looking at the closeup and now realize there appears to be some corrosion that I didn't see before.  Guess I'm going to have to go over this thing with a magnifying glass.

Offline
Last seen: 16 hours 49 min ago
Joined: Mar 31 2020 - 19:55
Posts: 383
DistantStar001 wrote:Update:
DistantStar001 wrote:

Update: I was just looking at the closeup and now realize there appears to be some corrosion that I didn't see before.  Guess I'm going to have to go over this thing with a magnifying glass.

 

This may help.

 

https://archive.org/download/Macintosh68kSchematics/Macintosh68kSchematics.tar.bz2

 

The LC III schematics are in that set. 

 

 

Log in or register to post comments