One more SE/30 with video issues

[Russianv]

Hi all, first post here, hope to get some help form more experienced members.

I recently got an SE/30 that had all Caps leaked and basically fell off the board as soon as I touch them, which made it easier to replace them, so I guess that's the positive side

But, after recapping, and probably damaging the sound chips with excess heat from the hot air station ( no sound now, had sound before), I get this on the display:



Any suggestions on what is causing that?

 

[ymk]

Check the data lines to the LS166 at UE8. One of them is stuck.

 

[Russianv]

Check the data lines to the LS166 at UE8. One of them is stuck.

Thanks I'll have a look

 

[Russianv]

Check the data lines to the LS166 at UE8. One of them is stuck.

So, UE8 and UD8 were looking not very well on some of the pins, so decided to replace both with new ones, and somehow managed to make it worst apparently, in the original pic the lines were behind the disk icon, now the lines are on top of everything, any suggestions?

Also, on the sound side of things, I just realized the sound works if I connect headphones to the board, but the internal speaker doesn't, seems to be good because it makes some cracking noise from time to time, ideas on this one?

 

[Russianv]

Also, I just checked all the traces (relevant to video signal) from the memory chips UC 6 and 7, to the correspondent Ux8 chips, all seem to be ok.

Sadly I don't have scope to test the signal from UC6-7 out of the video pins, not sure if there is a way to check it with a regular multimeter?

So what is left, bad Ux8 chip(s) or UC6-7?

 

[Russianv]

Oh well, I found the issue with the video now!

Turns out a traces broken between UE8 and UC6, something I didn't test before, I feel so happy about myself now hahaha.

Now only thing left is the sound issue, will appreciate a lot if anyone has any ideas about what may be causing that issue, no audio from internal speaker but perfect sound from output jack on the back.

 

[cheesestraws]

Now only thing left is the sound issue, will appreciate a lot if anyone has any ideas about what may be causing that issue, no audio from internal speaker but perfect sound from output jack on the back.

First thing to check: there's a switch hidden in that audio jack that is responsible for cutting off the sound to the speaker when a jack is plugged in. Those switches sometimes jam up with this result. Check to see whether that switch is permanently open.

 

[Russianv]

First thing to check: there's a switch hidden in that audio jack that is responsible for cutting off the sound to the speaker when a jack is plugged in. Those switches sometimes jam up with this result. Check to see whether that switch is permanently open.

Well, out of nowhere, after the video got fixed, I plugged the internal speaker back in and... sound on start up!!! I have never ever been happier about hearing that sweet bong hahaha.

Thanks for the reply and advice!

 

[cheesestraws]

Well, out of nowhere, after the video got fixed, I plugged the internal speaker back in and... sound on start up!!! I have never ever been happier about hearing that sweet bong hahaha.

Yeah, could have been a dodgy switch then that got freed up by plugging and unplugging the headphone cable. It happens.

 

[Russianv]

Yeah, could have been a dodgy switch then that got freed up by plugging and unplugging the headphone cable. It happens.

Highly likely.

Out of curiosity, how do you test that switch that gets stuck?

 

[cheesestraws]

Out of curiosity, how do you test that switch that gets stuck?

Just a multimeter in continuity mode across the switch pins of the audio jack on the logic board. I can never remember which pins they are and always have to look it up, I think it's on the schematic...

 

[Russianv]

Just a multimeter in continuity mode across the switch pins of the audio jack on the logic board. I can never remember which pins they are and always have to look it up, I think it's on the schematic...

Right, I’ll have a look at the schematic then. Thanks again

 

[joevt]

So, UE8 and UD8 were looking not very well on some of the pins, so decided to replace both with new ones, and somehow managed to make it worst apparently, in the original pic the lines were behind the disk icon, now the lines are on top of everything, any suggestions?

Your first picture shows lines that are stuck as white.
Your next picture shows lines that are stuck as black.
The black lines on the floppy are easier to see than the white lines on the floppy.

 

[Russianv]

Your first picture shows lines that are stuck as white.
Your next picture shows lines that are stuck as black.
The black lines on the floppy are easier to see than the white lines on the floppy.

ok, thanks