Short version, anyone know what Q3, Q4 and D3 through D6 on the IIci logic board are? I may be able to figure it out from the tiny markings and the list at sci.electronics.repair, but I figured I'd ask here first, in case it's already well known. I may not need to replace them, but their legs and pads are well covered in corrosion.
The long version....
I finished removing the caps and cleaning the pads on the box of 20ish IIcx boards I mentioned in another post, plus the two Q840AV boards. I still need to take them outside and spray and brush them with flux cleaner.
Anyway, I want to do all the solvent work in one batch, so I also got the three IIci's and one IIcx out of the attic. Two of the IIci's and the IIcx I think I got from the same source as the box of IIcx boards. While there are no batteries in them, one of the IIci's and the IIcx have battery damage. Both battery holders fell out. The IIcx floppy drive is rusty.
The inside of the case of the IIci is bubbled. Any special recommendations on cleaning? Or just general soap and water and maybe vinegar or baking soda scrub.
I expected my original IIci (different from the two I got with the box of IIcx boards), the one I got back in the early-mid 90s to be in great shape. True, I had to recap the board in '97 or earlier and repair trace damage way back then. And some of the clips on the plastic SIMM sockets were broken. And back then I did the recap with more electrolytic caps, because I didn't know any better yet. Also, around 2002 or 2003 I pulled all of the ROM chips off in support of Gamba's and my homebrew IIci SIMM for SE/30s.
The reason I expected this well used IIci to be in great shape, is that in 2003, after removing the ROM chips, I replaced the whole logic board with a brand new in service parts box IIci logic board with nice metal clips on the SIMM sockets.
So, I pulled the logic board and visually examined it, and there is no visual sign of goo on the logic board -- until I look at the legs of chips near the caps. Corrosion city.
The lesson there, which we've learned before, is that even if you don't see the capacitor goo, there is probably still leakage and corrosion. How often have folks posted, "but I don't see and goo"?
I gently bumped one of the 74hc132 chips (14 pin SOIC) with my soldering pencil and it popped right off the board. Simiilarly for one of the resistor packs near the serial ports.
Upon cleaning, the solder pads appear intact. It looks like the solder just dissolved and released the chips and gooed up the board and chip legs with some kind of corroded residue.
What does the group mind think? Is it worth cleaning up those 74 series chips, or should I just order new? What do you recommend for cleaning this corroded solder mess off of the pads and the pins? Solder flux and heat and solder braid seems to just smear it around.
The long version....
I finished removing the caps and cleaning the pads on the box of 20ish IIcx boards I mentioned in another post, plus the two Q840AV boards. I still need to take them outside and spray and brush them with flux cleaner.
Anyway, I want to do all the solvent work in one batch, so I also got the three IIci's and one IIcx out of the attic. Two of the IIci's and the IIcx I think I got from the same source as the box of IIcx boards. While there are no batteries in them, one of the IIci's and the IIcx have battery damage. Both battery holders fell out. The IIcx floppy drive is rusty.
The inside of the case of the IIci is bubbled. Any special recommendations on cleaning? Or just general soap and water and maybe vinegar or baking soda scrub.
I expected my original IIci (different from the two I got with the box of IIcx boards), the one I got back in the early-mid 90s to be in great shape. True, I had to recap the board in '97 or earlier and repair trace damage way back then. And some of the clips on the plastic SIMM sockets were broken. And back then I did the recap with more electrolytic caps, because I didn't know any better yet. Also, around 2002 or 2003 I pulled all of the ROM chips off in support of Gamba's and my homebrew IIci SIMM for SE/30s.
The reason I expected this well used IIci to be in great shape, is that in 2003, after removing the ROM chips, I replaced the whole logic board with a brand new in service parts box IIci logic board with nice metal clips on the SIMM sockets.
So, I pulled the logic board and visually examined it, and there is no visual sign of goo on the logic board -- until I look at the legs of chips near the caps. Corrosion city.
The lesson there, which we've learned before, is that even if you don't see the capacitor goo, there is probably still leakage and corrosion. How often have folks posted, "but I don't see and goo"?
I gently bumped one of the 74hc132 chips (14 pin SOIC) with my soldering pencil and it popped right off the board. Simiilarly for one of the resistor packs near the serial ports.
Upon cleaning, the solder pads appear intact. It looks like the solder just dissolved and released the chips and gooed up the board and chip legs with some kind of corroded residue.
What does the group mind think? Is it worth cleaning up those 74 series chips, or should I just order new? What do you recommend for cleaning this corroded solder mess off of the pads and the pins? Solder flux and heat and solder braid seems to just smear it around.
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