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Sure - see below. Camera isn't great and seems to add a fair bit of "mushing" between the various elements, so it's hard to see on the right side... the lifted pads (& 1 slightly bent pin where I used a needle to check below) on PIXEL# are very visible on the bottom row. Sadly they came straight...

Found what the issue is - on two sides of the chip, the small traces under what looks to be (from looking at your diagram) HSYNC, VDDC, EVIDEO & BLANK, and also a few of the PIXEL# pins were destroyed by the corrosion - they aren't there at all. Perhaps with a supremely steady hand it would be...

Sure, could try that - concerned about separating the chip from the board... guess it doesn't matter at this point though.

Well, sadly, the reflow of the video chip was unsuccessful. It looks good, however now there's no happy chime. Probably my sub-par skills. Have gone over the board with a fine-toothed-comb, however it's going into the "for parts or repair" pile for now. Think it's time to start looking into...

Was wondering about them. I remember on the Mac Classic, there were 2 filter caps (or similar) that looked like this. Replaced them and it cleaned the "fuzz" right up, but nothing else. So, tried to boot the machine. Crt makes warmup "click" when power switch is flicked. The machine makes a...

Easy, perhaps a tin would be a good idea, however the connections are so tiny that am worried that even a huge helping of flux would stick them together. Regardless, have finished a recap & cleanup as best as possible. There was one lifted pad which was fixed with a tiny dangling connection to...

Excellent. Have both Mechanic's UV Mask & PCB Lacquer (solder-through) - better to hold off until testing the board? @GRudolf94 , thanks for pointing out the filthy comm slot, didn't even see - taking the card out & agitating the slot revealed acid the whole length of it. Had a vinegar bath...

Great info, thanks all. Have cleaned it up as above, special attention to comm slot (might be some underneath?). @Phipli thanks, it must be the 5500 then. Will have the computer brought to test. With the spray lacquer, what exactly needs to be avoided (conductive?). It cleaned up pretty well...

Thanks! After a few hours scrubbing with vinegar, this is the result: An awful lot of solder mask came off along with the battery. It's hard to tell if the traces are bad (my inexperience, likely). They don't look rusty, just exposed. Is it worth continuing, or recapping from here? Have...

Hi all, Have been asked to look at a LB from a 5400 / 5500 - PN # 820-0952B. Looks like it was battery bombed at some point. Apart from some revealed traces, and dirt, it looks fine, BUT it looks like there are 2 resistors missing R143/R144 - can't find any images of whether that's the case on...

Hi all, thanks for the interest. Yes, after shelving it for 6 months, twice. Ended up reflowing and double-checking work everywhere, as well as replacing a couple more things, and changing some caps for non low-ESR. It finally booted last month and voltages appear good. What a head-scratcher!

Moving onto a project that I've been dreading, a Color Classic LB with two lifted traces. Have added solder to each of the other capacitor pads. They are on C4 & C5, -ve legs. Looking closely, it almost seems as if I could scrape off substrate and attach some solder with flux to the little hole...

Yes, turning it up to 5v now produces 12.56v on +12v. Doesn't appear to affect screen. Also tried turning it all the way both ways all the way, and taking it off for isopropyl bath.

Okay so I replaced DP3, DP4, CNY17G, IRFBC40, and the 22k Resistor. Same problem, wavy screen lines. However, I now have: 5v: 4.74v 12v: 12.11v

Yes, it has been changed. Didn't make a difference. I still have the following parts to replace: DP3 and DP4, CNY17G, IRFBC40 Also have 22k ohm 3W resistor but struggling to work out where it is / why ordered

I wonder, could it have anything to do with the LB? Would it be worth recapping or trying a different LB?

Okay, so, filter caps replaced. Now it boots instantly without "jump-starting" ("tak-tak-tak-tak-boot"). Also carefully reflowed every single solder connection on the board @bibilit However, the wobbly screen still exists, and now these black lines come. No matter how much I turn PP1, can't...

Thanks @bibilit , @CircuitBored . I have ordered brand new filter caps - PME295 pcb mount cap,4.7nF 440Vac . Will see how this goes. Is there a particular orientation for installing them? @bibilit , much appreciated, toning down to under 12v currently produces ~ 4.45-4.5, will re-test after...

Thanks. Looks like they have a big crack down the middle, but good to know they wouldn't affect the current issue. Leaving it on for 5-10 minutes, the oscillation stays the same. At the final value I turned PP1 to, 12v stays at 12.74 and 5v climbs from 4.80 to 4.85 and stays there. No...

Sadly, none of these produce a stable picture. The picture is always slightly "wavy" (like low tide at the beach). Behind this, there is always the "plain" screen (like a desktop without title bar & icons, but with interlacing - line across screen is from camera picking up refresh: The...