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Ive never personally ran into it before, at least not yet but just looking at the pictures I can map the circuit out in my head pretty much right away and see whats going on, luckily.

yeah Q4 is the high-side VCC switch for IC3. Whatever happened with IC3 blows Q4. Q4 and Q9 are NOT zener diodes! They are transistors. Q9 shorts CN3 1 and 3 together when enabled. R48 is a pullup to keep the transistor turned OFF when not asserted by the control circuitry.

MOVs do have a lifespan so thats not surprising. Also a surge could have done this as well. the TOP226Y and 1ohm fusible resistor are a known weak spot in these PSUs, knocking out standby voltage. When the TOP controller fails, it opens the 1ohm resistor.

Did you leave the PRAM battery in there to corrode all over everything? its hidden and this is the symptom when it eats out the vias on the motherboard. I already lost a machine to this.

Oh damn I didnt get this notification since I use the 65HVD08 extensively in my product line, the DIP version.

Well if you publish your work on that, I am interested. The macintosh portable should work straight up since its basically a PB100

Are those archived anywhere?

Edit: nevermind, wrong thread.

Since this thread is gotten to become a huge tl;dr, I am interested. What machine specifically? Edit: Also, does anyone have a build of minivmac that works with this on Windows?

Could be a bent aperture grille from shipping. I dont know, id need to see a picture demonstrating the problem.

You need to buzz out the SCSI/SWIM bus pins back to the main system bus. the ASC/SCSI/SWIM share the same plane interconnect to the bus. it often breaks right where the 3 caps sit.

Coudl also be how they were stored/treated. The overwhelming number of portables i see, were always stored properly, and in their bags so they are still pearly white, so maybe due to its sheer price at the time, owners took more care. But by the time the 170 etc came out, people basically did...

Tunnel vision does the exact thing before the corners turn dark. I have a portable display that does it. after 15 minutes of it being on, it starts to create an after-image/ghost, and then not much longer after that, the corners start to darken.

I have a portable LCD that has tunnelvision. Whats interesting, is i come into some information from an Apple system alert that indicates when these displays were NEW! tunnelvision was somewhat of a problem. Look at this: This tells me the displays always had this problem, its just, its...

Entirely possible. especially if 5V hit any of the I/O lines before the VCC had settled, itll blow things up.

Not crispy becuase you replaced the analog board. You gotta recalibrate it. Focus, G2, and H-STAT for convergence.

Screen? recap. I already did a video on a 165c. they are through-hole caps, and eventually they will leak. They all do.

dealing with polarizing film in general is pain. the hardest part is getting it aligned exactly right, but also no debris between the sheet and the glass stuck to the adhesive on application. like applying phone screen protectors, it sucks and its not fun.

You are missing a voltage to the video amplifier/driver stage. Need to find out which fusible resistor burned open and check for a diode that shorted.

yeah I bet the bus transceiver failed