Ultrasonic cleaner appears to have killed my Quadra 650 board....

lobust

Tinkerer
Nov 14, 2021
51
34
18
Man I am having such bad luck with this.

I bought another board recently after multiple failed attempts to fix the scsi bus on my Q800.

The board I bought had been battery bombed, but the damage was really minimal and it still worked just fine. It had some very minor trace damage and corrosion around the battery diodes and U63 which I repaired, and the board was working great with a new battery.

As the last step I decided to clean it in the ultrasonic cleaner to remove the last remnants of battery gunk and flux, although there was very little of either. I stripped the board bare, including removing the CPU, and gave it 4 minutes a side at 50degrees, rinsed with warm water, blew it off with compressed air and left it to dry.

Now it's dead, sort of. It chimes loud and clear, but it seems to hang immediately after that. The reset button works, but the interrupt button does not trigger the death chimes. There is no video output, either onboard or nubus video card, and no boot activity from any drive.

Anyone encountered this behaviour on a wombat board before?
 

YMK

Active Tinkerer
Nov 8, 2021
358
285
63
Too much time in the cleaner can snap the leads off rectangular SMD caps.

You can't tell by looking at them, until you give them a poke with tweezers.
 

Patrick

Tinkerer
Oct 26, 2021
434
1
224
43
is 4 minutes a side "too much time" ? (asking honestly)
 
Last edited:

jajan547

Active Tinkerer
Mar 25, 2022
732
295
63
North Carolina, USA
Man I am having such bad luck with this.

I bought another board recently after multiple failed attempts to fix the scsi bus on my Q800.

The board I bought had been battery bombed, but the damage was really minimal and it still worked just fine. It had some very minor trace damage and corrosion around the battery diodes and U63 which I repaired, and the board was working great with a new battery.

As the last step I decided to clean it in the ultrasonic cleaner to remove the last remnants of battery gunk and flux, although there was very little of either. I stripped the board bare, including removing the CPU, and gave it 4 minutes a side at 50degrees, rinsed with warm water, blew it off with compressed air and left it to dry.

Now it's dead, sort of. It chimes loud and clear, but it seems to hang immediately after that. The reset button works, but the interrupt button does not trigger the death chimes. There is no video output, either onboard or nubus video card, and no boot activity from any drive.

Anyone encountered this behaviour on a wombat board before?
I have a SCSI chip for that board.
 

lobust

Tinkerer
Nov 14, 2021
51
34
18
Too much time in the cleaner can snap the leads off rectangular SMD caps.

You can't tell by looking at them, until you give them a poke with tweezers.
Thanks, I'll give it a look over. I kind of suspect there is a trace or two somewhere on the board that was marginal before and is broken now...
is 4 minutes a side "too much time" ? (asking honestly)
I would like to think not, but I'm prepared to be wrong. I have US'd boards for quite a bit longer than that before with no issues, but those were mainly industrial pcb's that are less complex and more rugged...
I have a SCSI chip for that board.
Thanks, I have a few too thanks to another member. Unfortunately replacing it has no far yielded no results on that board which is why I backburnered it and bought another board. It seems that everything that should have continuity has continuity, and the somewhat complicated active termination circuitry seems to be working as best as I can tell. I have a suspicion that the IOSB chip might not be fully working as the board behaves the same with the scsi chip completely removed, and I had intended to get a logic analyser and compare the working board to the dead board...
 

lobust

Tinkerer
Nov 14, 2021
51
34
18
I've got the board that died in the ultrasonic cleaner working again. I'm not sure exactly which of the steps below fixed it, but here's what I did:

1. Removed U63 (I think this is the RTC?) and resoldered it. I had previously only poked around the legs of it a bit and concluded they were all still attached, but I think a few of them were marginal and were only connected by heavily corroded solder which got eroded away in the uc. Most of the NC pads were completely detached from the board, so I guess the battery gunk was not completely impotent... One connected pad was detached from the board but still attached to it's trace, so I put a dot of UV mask on either end of it to hold it in place.

2. Some of the dram ic's next to U63 had some pretty dull solder so I resoldered them.

Given my run of shitty luck with these boards I fully expected this to be unsuccessful, so I'm quite relieved with the results!
 

jajan547

Active Tinkerer
Mar 25, 2022
732
295
63
North Carolina, USA
I've got the board that died in the ultrasonic cleaner working again. I'm not sure exactly which of the steps below fixed it, but here's what I did:

1. Removed U63 (I think this is the RTC?) and resoldered it. I had previously only poked around the legs of it a bit and concluded they were all still attached, but I think a few of them were marginal and were only connected by heavily corroded solder which got eroded away in the uc. Most of the NC pads were completely detached from the board, so I guess the battery gunk was not completely impotent... One connected pad was detached from the board but still attached to it's trace, so I put a dot of UV mask on either end of it to hold it in place.

2. Some of the dram ic's next to U63 had some pretty dull solder so I resoldered them.

Given my run of shitty luck with these boards I fully expected this to be unsuccessful, so I'm quite relieved with the results!
Awesome happy to hear it boots wanna provide some pics of it booted?
 

lobust

Tinkerer
Nov 14, 2021
51
34
18
Awesome happy to hear it boots wanna provide some pics of it booted?
Sure, excuse the mess, working in a half finished room right now 😁
AA7956E3-04C7-47F3-8F6B-D25A24759C46.jpeg
 

Patrick

Tinkerer
Oct 26, 2021
434
1
224
43
is the heatsink on the CPU something you added or was it standard on the higher end quadra's?
 

lobust

Tinkerer
Nov 14, 2021
51
34
18
is the heatsink on the CPU something you added or was it standard on the higher end quadra's?
Standard I think, although I'm not sure how many different types of heatsink there are or which Quadras came with them.

I have two 650/800 boards and a 700. The original 800 board and the 700 both have an extruded aluminium heatsink that clips onto the socket with a seperate clip.

This one clips directly onto the cpu rather than the socket.
 

Volvo242GT

Tinkerer
Feb 7, 2022
307
167
43
Currently Duvall, WA
Most 650/800 boards I've come across have had the heatsink that clips onto the socket. I once received a base model Quadra 650 board (4MB RAM, no ethernet, and a 33MHz 68LC040) that had the other style heatsink that clips onto the chip itself.

@lobust If you want your Q800 to think it's a Q650, add the power LED to the board, near the front edge. That's the only difference between the Quadra 800 and Quadra 650 with ethernet boards. On my last 650, I installed an 800 board into it. Machine identified itself as a Quadra 800 until I had a friend solder on a power LED in the spot for the Centris/Quadra 650 boards. Once that was done, the board properly identified itself as a Quadra 650 board.
 
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lobust

Tinkerer
Nov 14, 2021
51
34
18
@lobust If you want your Q800 to think it's a Q650, add the power LED to the board, near the front edge. That's the only difference between the Quadra 800 and Quadra 650 with ethernet boards. On my last 650, I installed an 800 board into it. Machine identified itself as a Quadra 800 until I had a friend solder on a power LED in the spot for the Centris/Quadra 650 boards. Once that was done, the board properly identified itself as a Quadra 650 board.
Already done ;) - in the photo you can just see the wired led poking out from underneath the scsi2sd!

This board has been tinkered with before I think, as it had both the onboard led and the header for the 800 led, but also both speaker header places were populated.

Maybe that's normal for a 650 board? I have never had another one to compare. I removed the onboard led in any case.

There are two other differences between this 650 board and my 800 one, this one has the rom socket populated, the 800 does not, and this board is the typical green colour, the 800 board is a very dark green/copper brown colour which I like better if i'm honest!
 
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Volvo242GT

Tinkerer
Feb 7, 2022
307
167
43
Currently Duvall, WA
Yep. the 650 boards have both. Same with the speaker headers. I'll have to look at my 650 when I reinstall the hard drive into it and see for sure, but I think the ROM simm slot on it is empty, so it's running on the onboard ROM chips.
 

imactheknife

New Tinkerer
Jun 28, 2022
23
1
3
Hey there, just want to ask a question or three I have a quadra 800 that had some battery damage. it took off the diodes, and some legs off u63. It still chimed though. the battery holder was toast. the crystal was toast too. I ordered new parts and after cleaning up pads I dont get a chime or anything now. It turns on, led lights up but no display. I had to do some surgery to U63 to fix legs and pads. If U63 isn't working will it cause this? I haven't replace battery or battery holder either. Thank-you for any info. Mark
 

jajan547

Active Tinkerer
Mar 25, 2022
732
295
63
North Carolina, USA
Hey there, just want to ask a question or three I have a quadra 800 that had some battery damage. it took off the diodes, and some legs off u63. It still chimed though. the battery holder was toast. the crystal was toast too. I ordered new parts and after cleaning up pads I dont get a chime or anything now. It turns on, led lights up but no display. I had to do some surgery to U63 to fix legs and pads. If U63 isn't working will it cause this? I haven't replace battery or battery holder either. Thank-you for any info. Mark
Which chip is U63?
 

jajan547

Active Tinkerer
Mar 25, 2022
732
295
63
North Carolina, USA
Hey there, just want to ask a question or three I have a quadra 800 that had some battery damage. it took off the diodes, and some legs off u63. It still chimed though. the battery holder was toast. the crystal was toast too. I ordered new parts and after cleaning up pads I dont get a chime or anything now. It turns on, led lights up but no display. I had to do some surgery to U63 to fix legs and pads. If U63 isn't working will it cause this? I haven't replace battery or battery holder either. Thank-you for any info. Mark
Here you are.
 

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imactheknife

New Tinkerer
Jun 28, 2022
23
1
3
I think you were helping me on 68kmla. It is right beside the crystal and diodes / battery. The one leg of d4 has a trace that goes back to positive side of battery i believe. Some pads came up from u63 and had some legs corrode off of u63 so had to dremal chip and use wire to reattach legs to traces. Just wondering if someone has a spare u63 just in case?
 

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