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I installed the Top Cover Interlock switch today on the DC Power Supply and I am still missing the 24v power circuit. Tomorrow I will install a new Triac on the AC Power block. I am reading good steady 80 ohms. On my other AC Power block I was getting random readings. Thankfully parts are...

Thanks for the suggestions. I have replaced the AC Power block and recapped the daughter board with the green 22uf leaky capacitor. I have also recapped the DC Power Supply, the High Voltage power supply, The DC Controller PCA and the IIg Controller Board. I was able to get the two red lights...

Wowza! I have two battery bombed boards and would love to try transferring my good parts onto a recreation board. I was never able to get past the Death Chime on them. I'm guessing internal layers were damaged near RAM bank A from a combination of battery and capacitor vomit. Incredible work.

I'm guessing recapping the power supply(s) next. I found this great old Apple Service Training video

Last year I bought a Mac II and the owner gave me a LaserWriter IINT that had been sitting for decades in his basement. It's very clean, just dusty. I bought a LaserWriter IIg controller board and recapped it and installed it in the printer. At first I got a no paper flashing light with the...

This gives me new hope. I put the PowerBook aside because of the frustration. I will take a look at the vias this week. Thank you for the assist.

I have two PM7100's one with the G3 card and one without. Both of them has this same issue of no chime, no video on three motherboards. This last occurrence happened when I upgraded the RAM. I replaced the old RAM and still nothing. My workshop is in my basement so not much chance of static...

The PM7100 is a huge pain to work on. I have three PM7100 boards all with the same issue - no chime, no video. This one has a Sonnet G3 card, but I remove it to add the standard video card. Yesterday on my working PM7100 it booted fine before shutdown and added new 32mb RAM to bring it to...

I bought a couple of these sets for my Mac IIx a year ago. They are great, but I would place some solder onto the pads to give them some extra thickness to connect to the socket. I wasn't able to boot until someone suggested the soldering trick. It's just that the PCB's are thinner than the...

Here's a YouTube tutorial on how to jump start the Mac II

It is possible to "jump start" the Mac II's to bypass the startup circuit on the motherboard when trying to figure out a startup issue. I made my own using a AA battery holder (similar to the link) with the two wires attached. I soldered on some alligator clips. You just need 3v, touch the...

The Startup/ Shutdown Nand Gates for the IIFX are UI18 and UJ18. UI18 is the shutdown Nand Gate that most likely has a broken trace preventing it from shutting down. Usually C24 and or C27 leaked on the traces. If you check voltages at the Nand Gate UI18 with power on you should be able to...

Thanks for the encouragement. I will keep trying. This is still a great project.

Not much luck. I am having issues with programming the GAL's properly. I have tried several of the suggested settings in Xgpro including GAL16V8D @SOIC20 no encryption and voltage set to 12v. (I have tried default settings as well encrypt and 16v and selecting just GAL16V8D). I still get a...

Oh I can appreciate how difficult it can be to make a board. I was lucky enough to find working replacement iifx boards. Kind of sad I wasn't able to get them to boot properly. Which is why I hope a new board can be made like the SE/30 reboots. It is remarkable with the efforts being made. I'm...

Wow that great! I have two FX battery bombed boards that both give me a death chime. I'm guessing somewhere there are broken traces from the battery goo that seep through the vias onto the interior layers. It would be great to do a rebuild the board. It looks impressive.

Nice work. I looked at that FX board and decided to pass on it. I'm glad you were able to work on it.

Wow this is great. My 512k suffered some damage from a leaky battery. Thank you.

I'm interested in the rear case bezel with the motherboard connector cutouts. Let me know how much including shipping. PM me with info. I'm in Michigan.

After a few years of working on my two Mac IIfx boards, I have put the repairs on pause. I actually was able to purchase a clean board on eBay last year and have that working. This month I was finally able to purchase another replacement Mac IIfx board. So now I have them both running again...