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Couple of question here: is there a pullup resistor on the board for the data line? If so, you probably should not /drive/ the pin as an output, but configure it as open drain, this is pretty much to ensure both end are not driving the pin at the same time (which would damage both drivers)...

Right, I've added a bit of sponsorship to @Kai Robinson for my wall-board, if anyone else feel like helping, remember you would be hard pressed to find something you would hang on your wall for less than  £30 :-) Also, on a side topic regarding the attiny85 RTC chip, I'm the author of...

Actually I'd like to do the same, ie buy a dead board to support this awesome project :-) Also in the UK, PM if if suitable.

Thanks for the tip. I had a poke around; probe on the ground pins at the connector, and measured resistance at the + of all the SMT caps, radialy.  And yes /most/ of the board reads about 16 ohms -- give or take -- , but around the 74hcs I have replaced, it reads 3ohms on the VCC... I removed...

So well, not so good as it turns out. As soon as I slotted the batteries in I heard a little "click" noise from the part of the board near the power button or thereabout. Removed the batteries of course... I got investigating, and there is a short on the main rail! Almost everywhere... that...

I'm currently doing the same job, and I decided outright to change UB1 and UB2 -- make sure ALL the traces connect while the chips are off the board, as on my board, some of the traces between UB1&2 were corroded enough to remove connection between pads. Also check on the power button side...

Anyway, project still ongoing, as I had quite a few other thing to do recently. However today I did 'recap' the whole board, and I just have to re-install the SOIC14 x4, then add a couple more wires (for failed traces on the pads there). I only have one worrying trace I can't do anything about...

Ok so today I did another run at the Mac II, discovered a couple of extra traces that were cut (some are quite subtle!!) near the power switch. I ended up cleaning the thru hole cap holes with the tiniest drill bits and that was a lot less stressfull than all the other attempts and methods I...

Where's the +1 button around here :-)   :-) Thanks @Michael_b and @blusnowkitty

Ah good tip, in fact, excellent idea! I also have hot air so I'll try that next. I've been sulking for a day or so because of that problem so it gives me "options" :-)

I got 2 of 3 of these, I even have the 'heated tip' one... doesn't help much. I think I'll have to try the "iron heating one side of the board, pump on the oher side" and see if that helps..

Ahaha, I'm an expat. I worked for Apple ER&D in the 90's on the Djinn and Apple Telecom 3.0 (and a few other bits) -- but I moved to the UK in '99 ! So you were both right :-) @joshc yes I picked that machine in the UK near Ash, I'm near Maidenhead myself. Thanks for the tip on...

Yep, that's the one! Well ahead of it's time, as apple was, at the time...

Thanks, I do try all of these, add solder, add flux, use 400C on the iron etc etc not much luck. Well i cleared about 2/3 of them using various combination of these, but some are just... tough!

Some more work today, cleaned all the caps locations; added 3 new wires, the worse being around the cap near the Apple Sound Chip, there's 3 traces there WAY close to the cap, and these got damaged. Only one needed a wire tho. I also saw a couple of traces that look 'dark' but one diseapear...

I've desoldered my thru hole caps, but the hole is now 'full' and no amount of heat and manual desoldering pump seems to help. Do I have to re-drill the center with one of these tiny bits? Seems some of the holes are straight onto a power plane, so they act as heatsink...

Well, so work has started; I got all the parts, removed all caps, removed the UB1/2 and the SCC drivers started cleaning the joins, scraping the vias and looking for corroded traces. Already repaired one near the ROM, where one of the long tracks near the C7 label looked corrored, so I scapped...

So does anyone have made one of these? do they work? I really like the fact the SD card isn't a 'special' format so I can copy/backup disk images from/on it...

I was pondering that actually, but, I couldn't find a coin cell holder that would 'look' nice in the place in question. If you have any suggestions I'd go for that as (like everyone) I don't trust these 1/2AAs -- never did, they used to fail even back in the days! Also, any suggestions on what...

Hi Everyone, first post here. I used to be a Mac developer, between maybe 1986 until 2007. I still have a large collection of machines, and some prototypes, and I've been making myself a small museum in a spare bedroom, quite frankly really Apple II stuff. But then I manage to find a Mac II...