croissantking
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Thanks, but I’m afraid I binned the chip. I ran out of patience
croissantking's conquests
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croissantking
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Sorry, it’s too late now. I know shouldn’t have done this. I’ve got too much broken stuff piling up and I felt overwhelmed.
CC_333
Well-known member
Thanks, but I’m afraid I binned the chip. I ran out of patience
Well, it hardly the only 40 MHz '040 in existence.
While not exactly common, they're not particularly rare, either, so it's probably simpler to, sadly, throw it out and get another one if too many pins are damaged or missing.
c
Last edited:
pizzigri
Well-known member
Yeah, so next time you find one in this condition, send it over, I’ll happily pay shipping for it…
croissantking
Well-known member
While not exactly meaningful progress, I did figure out why the keyboard wouldn’t power on the 840AV. I had it plugged into the S-Video out Port
It looks identical to the ADB port and with the board outside the case, I didn’t realise. So, I hooked it up properly and I have keyboard power now. Command-Control-Power seems to work as far as resetting, as I can hear a faint pop from the headphones I have plugged in when I do this.I spent some time today cleaning up one of the boards (the brown one, with the ROM socket) a bit further with IPA and a toothbrush, as a white residue was still present between the legs of many of the chips. I also checked continuity on a few of the worse looking traces that had turned a black colour, but they all tested good.
No chime or video yet. I’d better check that the 040 CPU actually works. While I’m sure it does, I’ll stick it in my Carrera040 accelerator later to be certain.
Maybe. Or bad vias? Or faulty chips? It’s a very generic failure mode, unfortunately.
croissantking
Well-known member
A big Quadra update today.
I was poking around one of the boards this morning looking for broken traces and I found one adjacent to the AT&T DSP. It really didn't look broken at all, but it was. You can't easily tell with the brown PCB. I ran a repair wire over the break:
I then decided to give the board a test, not really expecting anything different. But... as @Mac84 once said, it chimed! And not only that, but I got video. It boots off both a disk tools floppy and off a SCSI hard drive. Ethernet works, video and sound work. As far as I can tell, it's fully functional. And it is rocket fast.
The DSP is a secondary system, so I'm surprised that a single break here would prevent the machine from chiming. Another oddity is that the machine will chime, then hang, with no RAM installed - other Macs I've used will chime normally and then immediately death chime. The 840AV does have a death chime (a quite amusingly silly one at that) but I had to invoke it with Command-Power to hear it.
With many thanks to @GRudolf94 for their brilliant ATX adapter, which I wouldn't have been able to do without, as my original PSU is dead.
I will look at recapping the PSU and see if this brings it back to life. To be honest, it would probably be more pragmatic to adapt an ATX PSU... but I like the idea of restoring the original components.
I will also turn my attention to the green 840AV board - it has been a bit more seriously ravaged by cap and battery juices, but I ought to try.
I was poking around one of the boards this morning looking for broken traces and I found one adjacent to the AT&T DSP. It really didn't look broken at all, but it was. You can't easily tell with the brown PCB. I ran a repair wire over the break:
I then decided to give the board a test, not really expecting anything different. But... as @Mac84 once said, it chimed! And not only that, but I got video. It boots off both a disk tools floppy and off a SCSI hard drive. Ethernet works, video and sound work. As far as I can tell, it's fully functional. And it is rocket fast.
The DSP is a secondary system, so I'm surprised that a single break here would prevent the machine from chiming. Another oddity is that the machine will chime, then hang, with no RAM installed - other Macs I've used will chime normally and then immediately death chime. The 840AV does have a death chime (a quite amusingly silly one at that) but I had to invoke it with Command-Power to hear it.
With many thanks to @GRudolf94 for their brilliant ATX adapter, which I wouldn't have been able to do without, as my original PSU is dead.
I will look at recapping the PSU and see if this brings it back to life. To be honest, it would probably be more pragmatic to adapt an ATX PSU... but I like the idea of restoring the original components.
I will also turn my attention to the green 840AV board - it has been a bit more seriously ravaged by cap and battery juices, but I ought to try.
3lectr1cPPC
Well-known member
Congratulations!!!
croissantking
Well-known member
Thanks
. I’m surprised I didn’t have to fight more considering the state that many of these boards are in.
croissantking
Well-known member
I received this card from @jimbojones on eBay today. Now to see if I can get it repaired. Should be easier to tackle than the Radius card @mg.man gave me – I still haven't figured out that one yet.
croissantking
Well-known member
Today I assembled another PB 500 series CPU card with full 33MHz ‘040 chip. Works perfectly and FPU is detected as with the others.
Also been working on repairing my spare 840AV board. I found a loose pin on the DSP chip and decided to desolder it just because it was a total mess from cap leakage. I’ve cleaned up the PCB considerably and only lost a single pad, which isn’t too bad.
croissantking
Well-known member
Genuine chip quik is very expensive so I’m using something I got on ebay that’s similar. It’s not as good, but I use it together with a gentle application of hot air and it works well.
croissantking
Well-known member
Cleaned up the 840AV DSP:
Quite happy with it, considering it looked like this:
The little nubs on the corners of the chip make it so much easier to handle the chip without bending pins.
Quite happy with it, considering it looked like this:
The little nubs on the corners of the chip make it so much easier to handle the chip without bending pins.
croissantking
Well-known member
Got rid of the worst of the muck with IPA before desoldering. Then scraped off the corrosion with
croissantking
Well-known member
Couldn’t help myself to do one more task before I head off on holiday for nearly a month.
I resprayed a tired looking SE/30 metal bracket with a can of ZG-90. This was after using wire wool to remove a few bits of rust, and masking off the bits that need to be soldered later. This is the second one I’ve done and it really lifts the finished look of a Reloaded board. The paint doesn’t scrape off easily, in fact it adheres really well, which I’m impressed by.
I resprayed a tired looking SE/30 metal bracket with a can of ZG-90. This was after using wire wool to remove a few bits of rust, and masking off the bits that need to be soldered later. This is the second one I’ve done and it really lifts the finished look of a Reloaded board. The paint doesn’t scrape off easily, in fact it adheres really well, which I’m impressed by.
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