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Ok, so maccaps website is dead, and all the information it has hosted really isnt archived well on archive.org so I have no idea if the capacitor chart for the Analog Board, and Logic Board were on that site. its just gone now... So I am curious if anyone has the picture/capacitor map of the...

likely because of an address line not being muxed right. one of the 74F253s is bad. Find the one with the highest address lines and repalce it.

YES. physical appearance has nothing to do with electrical operation, at all The behavior is death chimes with additional RAM? then that is a major yes.

You don't, you replace them all. That is what I do. I don't question it anymore as I got tired of messing with dodgy chips. You can sit there for hours chasing your tail to figure out where the bad one is based on a logic analyzer or you can just replace them and save a whole bunch of time.

it looks normal to me, and even if it was sus, lets hope its not because there is no fix. that transformer is specific to that analog board.

There used to be a way to hack At Ease by going through the debugger prompt. I did this once or twice back in Jr High school but i will be damned if i remember what i did/how I did it.

Right here: one of the two 150uH inductors, the pin gets eaten away, and it fails. prevents that voltage from being generated.

In this case it was not. like I said it was a failure in the logic board, it was not providing one of the required voltages for the display.

I will have to get pics with the details, but here is the root cause: You are missing the twist voltage that drives the panel. its a 20 to 30v supply and its generated by the converter on the logic board. This voltage goes missing and that causes the black screen when the computer seemingly...

Logic

I helped a guy on Discord figure this out. there is an inductor that gets eaten away from cap goo and its impossible to see the failure, but its there.

No. Bolle's version is an entirely different design. its routed completely differently. You can use the schematic, but not the board layout.

Resolder the bad solder joints in the various spots on the analog board. This is a known issue on analog boards. Also, make sure you clean the adjustment pots with DeOxit F5. Everything should be good from that point.

the 74F258s will do this too if there is a bad/stuck line on one of them.

or you can just get old like I have, and you cant hear it anymore. haha. I cant hear the TV flybacks anymore either. quite nice actually.

looking at the corrosion pictures, especially around the 245, I bet there are broken traces. you will need to check/inspect all of them. Potentially remove that IC.

No, thats just how you repair transformers that have had issues with insulation, sealing and carbon tracking if its not too far gone. This dates back to the olden days with Tube type TV sets that used the wax covered flyback transformers. The result is the same even with modern transformers...

You have to cut out the cracks and check for carbon tracking first, otherwise you are wasting your time. Then once that is clear, you then have to bake the transformer to drive out ALL moisture. At this point, you dip it in a pot of hot boiling wax and that pot is sealable. once you do this...

You do you, so if you wanna just start throwing parts at it, be my guest... but, what you demonstrate in the video is normal.

No, i have not. because I have not personally encountered a machine with that problem. BUT... I do know that it will happen someday, as adhesives just naturally break down over time. it just, is what it is.. Look up 60s/70s color TVs and the PVA safety glass bond.