Just got an SE/30, have a display issue

[ifrit05]

Boot's up fine, but there's interference on the CRT. It looks like a bunch of lines and sometimes dots. I assumed it was due to some bad capacitors so I opened it up to take a look. Well, looks like someone already replaced pretty much all the capacitors with little SMD types.

Here is a couple of pictures of the board...

...And a video of the symptom I am experiencing

I'm thinking this is either the video circuitry on the logic board, the PSU, or the analogue board. I don't really want to mess with the analogue board, I don't wanna be exposed to any high voltages. Should I get this sent somewhere to replace them? I am able to solder but I don't want to screw this baby up. I'm actually surprised how little corrosion there is inside here, and someone already removed the PRAM battery so I guess they knew what they were doing. Worst fear avoided!

Any help would be appreciated!

 

[Compgeke]

When you say replaced with SMD, are they still the silver cans or a small brick? The silver cans are original and would need replaced.

 

[IlikeTech]

They are ceramic if you look at the pics.

 

[Bolle]

Can we get a closer look of the chips at UA8 to UG8?

It looks like there is some corrosion around them. One of them is probably on it's way out (UE8 most likely)

 

[Compgeke]

They are ceramic if you look at the pics.

Oh I see. Couldn't tell there were two links on my phone. Ignore me.

 

[ifrit05]

Can we get a closer look of the chips at UA8 to UG8?

It looks like there is some corrosion around them. One of them is probably on it's way out (UE8 most likely)

Uh oh, on closer inspection, it seems like the board is missing solder in some vias...

https://photos.app.goo.gl/hEzhW5BEphpx1HYC6

 

[ifrit05]

Sorry for the double post (is there a hidden edit button somewhere???), but after doing some more tests, I think it may be a voltage/PSU issue.

Here's a video of me putting a floppy disk into it.

https://photos.app.goo.gl/3EevpRpSz7mesqcb7

I think whenever the motor spins/head seeks the faint dots turn into lines all over. The SCSI drive has the same issue.

 

[techknight]

Ok looking at the pictures, the video circuit has definitely been reworked and UE8 replaced. 

As far as those lines coming and going, Been there done that. I have a SE/30 board here now that does that, and eventually the lines came back and never went away, and it sometimes depends on which objects are in front, etc... Never did figure it out. 

I highly doubt its a voltage issue. you have a lead likely going to UE8 thats barely making contact. instead of being a dead short like its supposed to, its got resistance in it. 

 

[androda]

Could reseating the RAM resolve this issue? If full columns are appearing and disappearing, then maybe those pins on the RAM simms are not making full contact? 

 

[ifrit05]

Ok looking at the pictures, the video circuit has definitely been reworked and UE8 replaced. 

As far as those lines coming and going, Been there done that. I have a SE/30 board here now that does that, and eventually the lines came back and never went away, and it sometimes depends on which objects are in front, etc... Never did figure it out. 

I highly doubt its a voltage issue. you have a lead likely going to UE8 thats barely making contact. instead of being a dead short like its supposed to, its got resistance in it. 

Yeah the Analog board looks fine, so does the PSU. I've already cleaned the board and scrubbed UA8-AG8 with 91 IPA and a toothbrush, no difference. Also, just noticed the lines are only appearing over grey colors, if there is a white area ("Welcome to Macintosh", backgrounds of open Finder windows, the menubar, etc.) it's fine. It's definitely a Logic board issue. I can solder but I'd rather send it to someone, I'm not that great at soldering small components. I live very close to maccaps (like an hour away), I'm going to shoot a message and see if I can get upcharged and redo some chips as well as caps.

Could reseating the RAM resolve this issue? If full columns are appearing and disappearing, then maybe those pins on the RAM simms are not making full contact? 

I have multiple times.

 

[techknight]

Yeah the Analog board looks fine, so does the PSU. I've already cleaned the board and scrubbed UA8-AG8 with 91 IPA and a toothbrush, no difference. Also, just noticed the lines are only appearing over grey colors, if there is a white area ("Welcome to Macintosh", backgrounds of open Finder windows, the menubar, etc.) it's fine. It's definitely a Logic board issue. I can solder but I'd rather send it to someone, I'm not that great at soldering small components. I live very close to maccaps (like an hour away), I'm going to shoot a message and see if I can get upcharged and redo some chips as well as caps.

That is the exact same problem I am having with another board that I have but mine is worse. I never did figure it out. If you do, let me know what it is. or was.

 

[ktkm]

The re-cap-job shown i the pictures looks like the works by Uniserver (Maccaps)! I had simular sympthoms with my ROM upgrade from BMOW. Try cleaning or switching to an other ROM.