Dead Mac Classic II - Can We Save It?

[@retrobitstv]

Sound is now working! It turned out to be a corroded trace under one of the caps. Thomas from Amiga of Rochester diagnosed and repaired the issue for me :D

[@ianpolpo]

For the At Ease password, I wonder if it's "Oxenfree" given the hint of "Ollie, Ollie"!

[@Viking_Cookie]

That was my first thought too

[@retrobitstv]

Totally didn't even think to try that. I will test it out and report back next time I open it back up so I can reinstall the HDD.

[@julianha2309]

For sound issue another tip: desolder the EGRET-Chips, clean the chip legs and the pads with IPA and solder them in again. Check, if any trace on the SMD caps on the upper right was accidentally was soldered to a trace where solder mask has gone (happened to me)

[@retrobitstv]

Thanks for the tips, I will definitely check these!

[@michaelsworkshop9031]

@19:58 the capacitance value being +/- ~10% of the listed value is common for capacitors like these, depending on grade; but the ESR is definitely far higher than expected. Check the rear audio jack - it has a switch inside that can get stuck out of position, eliminating internal audio. I would also try swapping the speaker with another known working one if possible.

[@retrobitstv]

Cool, thanks for the tips. I did spray some contact cleaner in the jack and plugged/unplugged a cable a bunch of times but I will try to see if I can inspect it more closely.

[@angrydove4067]

Great job and good looking solder joints. You will love the BlueSCSI, I sure do, using Basilisk II to make the drive image and you have your Mac always backed up.

[@retrobitstv]

Thanks! I will be looking into a BlueSCSI ASAP!

[@dave4shmups]

Great job restoring this Mac! I never played Dark Castle, but I did play a lot of the sequel, Beyond Dark Castle, on my Dad's Macintosh 512K.

[@retrobitstv]

Thanks! I will have to check out the sequel. I need more stuff to load on the machine anyway :)

[@75slaine]

Fantastic restore Matt, you made that surface mount work look so easy.

[@retrobitstv]

Thanks! Nothing like watching a lot of other KZbin videos beforehand to prepare :)

[@geekwithsocialskills]

That Macintosh Classic II came out really nice! Great job on the surface mount recapping.

[@retrobitstv]

Thanks! I'm really pleased with the result and glad I didn't ruin the board. Now to get a BlueSCSI and the sound working.

[@iamdkk]

Based on the schematic I would remove / clean and/or replace U1 next which seems to be the audio op-amp and is right near those caps.

[@retrobitstv]

Thanks for the tip! I did previously re-solder the pings of the op-amp but I didn't remove it entirely to inspect/clean.

[@dorfschmidt4833]

Check the vias under the SMD capacitors for continuity.

[@retrobitstv]

D'oh, that means I have to remove them again huh :/

[@rager-69]

Great job! I'm always amazed at Adrian Black's repairs and realize they are out of my reach. Your videos seem more doable for me.

[@retrobitstv]

Thanks! I also enjoy Adrian's videos and hope to someday be able to diagnose problems like he does, but I've only been doing this a short while and am still learning the basics. Baby steps :)

[@darkwinter6028]

Well, that sure cleaned up nicely!

[@JeffTiberend]

Looks wonderful! This was my first Macintosh. I loved every moment with it.

[@RacerX-]

Nice restoration! I have the same Mac only mine is badged the Performa 200. I recapped it years ago but I don't think I did the analog board. Guess I better recap to be safe. Thanks for the great video.

[@retrobitstv]

Thanks, glad you enjoyed it! At least with the analog board it's all through-hole caps :)

[@Otakunopodcast]

Beautiful board restoration, and great job with the surface mount caps! And ohhh yeah, leaky cap juice certainly has a distinctive odor, doesn't it? ;-) And a great tip re safety glasses, something I completely forgot to mention in my comment on your previous video. Yeah, those things do have a tendency to go "pop" sometimes, although usually this only happens with newer caps... older dried-out or leaked-out ones generally don't have enough electrolyte left to go "pow!". Still, best not to take any chances. :) Sorry to hear (well, more accurately "not hear" ;-) ) that the sound wasn't working tho. :(

[@retrobitstv]

Thanks! I will keep plugging away at it and get the sound working - how hard can it be? :)

[@ando8262]

Very just wow

[@1BitFeverDreams]

Nice video, shame about the sound. It's unfortunately always a hard fight for machines of this era and there seems to be no consistent solution for it.

[@kenknight5983]

This might be a little too obvious, but are the small tracks going out from the sound chip all unbroken?

[@retrobitstv]

I didn't see any that were damaged but I will have to take a closer look with some magnification and tone out the traces too.

[@tetsujin_144]

Nice. I'm still trying to get myself a compact mac that hasn't been battery-bombed to hell...

[@retrobitstv]

Yeah I got lucky that this one appears to have had the battery replaced. Some really post-apocalyptic looking logic boards out there.

[@anotheruser9876]

So the speaker doesn't work. Does the headphone port work at all?

[@tetsujin_144]

Does the speaker cut out when a headphone is inserted? If so could the machine think there is a headset plugged in? I guess plugging in a headset is the first step to testing that possibility...

[@retrobitstv]

I tested the rear jack with some headphones as well as some powered speakers and no sound comes out. There is a small "pop" when the machine is powered on which makes me think perhaps the little amplifier chip is working at least.

[@lilbluefoxie]

How do you prevent the apple logo from fading with that retrobrite process?

[@retrobitstv]

It got faded :( Next time I'd either remove it first or possibly put tape over it so it doesn't come in contact with the peroxide solution.

[@darkwinter6028]

There’s also a new FPU card available, IIRC…

[@geekwithsocialskills]

He mentions this around the 3:08 mark in the video.

[@darkwinter6028]

@@geekwithsocialskills I thought that he was referring to the old one that was available in the ‘90s? I’m thinking of an entirely new design; I think it was for the Classic II… anyway where I read about it was on 68Kmla…

[@retrobitstv]

I just learned about that new FPU board on Twitter within hours of finishing this video! But yea, I read somewhere in my research that at least one, possibly more third parties created FPU cards for the Classic II back in the day which seems to be corroborated by some forum posts and old eBay auctions but details are slim.

[@Stefan_Payne]

My reccomendaation for SMD Capacitors: Just use 2 Soldering Irons, 2 handed and just flip it off. That should work well enough for this job.

[@dennisp.2147]

The password has to be oxenfreed...

[@retrobitstv]

Didn't even occur to me to try that. I will next time I get the HDD hooked back up!

[@markdjdeenix6846]

It’s probably via damage

[@retrobitstv]

I'm ready to admit that's a possibility but I'm hoping it's something else simple that I missed. There are some small tantalum caps on the back side of the board that I didn't replace but I guess I need to inspect and test those as well.

[@markdjdeenix6846]

@@retrobitstv yes hopefully a simple fix

[@Coffeeology]

I bet the password is oxenfree