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Managed to ruin the ends of three traces while removing dead mask ROMs, only on the final chip. Everything was going smoothly until the last possible moment. At least the bodge wires will end up snugly pinned beneath the DIP socket, but it'll be weeks before I forgive myself for blemishing such a pretty logic board...

I'm beginning to think there is some ROM issue with my card. I was wondering if you happen to have an EPROM reader/writer? If so, would it be possible to read the data from your working cards ROM and post it here? What also would really help is a decent, well lit, 4k photo of the chip side of a working card. Who knows, maybe my card has a naughty chip in use on it.

Still some infrequent and minor twitching on my SE's video, so I took the final step* and recapped its ASTEC power supply. There was one small area that looked like cap ooze had been there. Now, the suspense begins.. either the video is now spot on, or after a long while it'll do it again. (* things like the flyback etc. are just out of my league, and the problem is too minor to risk those )

16MB feels like 256GB today

Gonna try dropping by tomorrow… not sure if they will have anything.

Bot Invasion!! Whoop whoop whoop!

Someone sent me the Apple schematics for the Macintosh Classic II!
They are now available on MacDat: https://macdat.net/repair/apple_schematics.html

My "new" IIci's soft power was stuck always signaling on, but I found the three micro-breaks in the relevant traces. Wish I'd spotted them during the board washing, but oh well. Humorously, both could've been fixed by simply bridging pins, but I wanted to make this look as elegant as I could, so as not to confuse any future owners.

And in a completely predictable move as was prognosticated by everyone who knows me....the sickness is spreading

Successfully moved a 466Mhz 7400 CPU onto a G3 CPU card - harvested from a Digital Audio card that I obtained for peanuts. The cache chips are rated at 250MHz, so I guess this thing will easily do 500MHz.

The old 750L will go onto an iMac trayloader CPU card.

I was born in 2001, but man I sure do love 1980s computers! I wish I could go back in time for just a little while and see these machines in their heyday.

For a few days there, every Mac I own was up and running perfectly. Well, the Q605 still has some very faint digital noise ingress on audio, OK since that was a board with a lot of bad traces. But today the IIcx that had one corrupted ROM stopped chiming. Still boots with a ROM SIMM. Debugging..

Finally got the WiFi Dayna port emulation setup on my external BlueSCSI with my Mac SE so I can now browse the web! It decently fast too thanks to the MacEffects accelerator I have in here! This is the SE setup I always dreamed of, and it's now possible at a very reasonable price thanks to these wonderful new products for these machines.

Does anyone else think OPTi 'Firelink' is misleading and just a bit off? I mean, it implies it could be a Firewire chip.

Got some OPTi chips for future Personality card mods. The plastic wrap on these Chinese imports always smells of citrus.

Hosiden - "Causing Mac users pain and suffering since 1987."

Got a hold of a cheap IIci and made the logic board sparkle again. Lifted dull-looking chips, cleaned the legs and pads, drag-soldered back fresh. Nice new caps, no broken traces in the acid zones, power circuit works. However, either the ROMSEL circuit or the ROM chips themselves are again bad, like in my IIcx, though the machine works great with a slot ROM. Am I cursed to irradiate every mask ROM I touch?!

I bodged a dedicated reference crystal onto my Beige G3’s ATI chip, which means I can play around with the main reference crystal without losing onboard video.

I'd seen mentions of cursors flickering on some Macs because of time/RTC related problems. After taking a closer look at the RTC circuitry in my cheap Mac IIcx, sure enough, it's not the video card! After scraping, tinning, and meticulous bodging, it's all right.