Recent content by PacificState

Update - I think this is an internal drive problem, rather than one with ADTPro, as writing to my external 5 1/4 drive works fine. Things I've done so far: - Cleaned the heads using a head-cleaner disk (soaked in 99% isopropyl alcohol) - Lubricated the head rails (if that's the term) - Adjusted...

I'm bootstrapping my Apple IIC (x2) machines with ADTPro running on M2 MacBook Air via an FTDI adapter - and while I can transfer data, I can't successfully write out disks. The problem is hit whenever I try to write an image via the ADTPro software running on the IIC. Whilst the transfer is...

If it’s the original II power supply, it has no temperature control. What voltage do you get when you measure?

So, it works! I was able to boot to Finder with a few caveats: - The motherboard and PSU are missing the screws. From https://68kmla.org/bb/index.php?threads/macintosh-iifx-misc-screw-size-repairs-1989-memory-and-box.46770/, these are part number 426-3401, and replacements with captive lock...

Thanks; I actually went like-for-like and swapped in a 25V tantalum at C1 and two 25V electrolytics elsewhere. I still can't figure out why the mix of capacitor types was chosen, though!

I was definitely confused when I put it all back - there’s 5V on the main board which is used to power the LED (even though IIRC this is labeled as for the fan!), and ~9V on the ‘riser’ board which is actually the fan connector (I’m not sure this is the expected voltage, but it’s what I got...

So the power supply is now recapped, with a new RIFA and fan. Few things for reference: - The cap listing in the link I posted above seems slightly off; you can actually buy a new pack of caps for this PSU Console5...

To close this thread out: - I couldn't relate any of the error codes to the MacSnap RAM layout (it's a 524E board, for reference) - Piggybacking a new chip over each existing IC in turn didn't get it booting - but I did notice that two ICs in particular caused vertical black lines to be...

Fixed after looking up the error codes (https://tinkerdifferent.com/resources/sad-mac-error-codes.82/ - it was precisely correct). Next problem: I have a MacSnap 512KB board which is throwing a similar RAM error when installed.

And... after desoldering the 6522 and IWM, the 68000 was dead :s I managed to socket them all without pulling a pin, and now I get a sad Mac and an 020100 error.

Hmmm, so it actually looks like the CPU reset line never goes high - it's held at about 0.4V, without ever nearing 5V. If I do hit the reset switch, it drops temporarily to ground but returns to its prior level. Furthermore, the scope shows that there's never activity on the data or address...

Having figured out the first of two Macintosh 128 boards I acquired (https://68kmla.org/bb/index.php?threads/macintosh-128k-board-with-custom-512kb-upgrade.48789/), I'm now trying to repair the second. I'll add pictures shortly, but it appears to be an 128KB board upgraded to 512KB, which...

Thanks! Unfortunately, mine is indeed the 699-0389 - presumably as it started life as a II. I'm not sure if there's a particular benefit other than the fan? Otherwise, I appreciate the pointer to the card. I do have an OSSC and BMOW sync adapter, so I might try those next once the PSU is repaired.

I recently purchased a Mac II that had been upgraded to a IIfx - it has the original case but an upgraded motherboard, and both an 800K and 1.44MB drive - and have been trying to get it running again: - Firstly, I installed new batteries and turned it on to get a chime - However, I was using a...

I believe those *are* Plus ROMs, as it also has a MacSnap SCSI card installed and I was able to boot System 6.0.8. Anyway, this is a little bit of a curio for me as I haven't seen another board wired like this before - I'm definitely interested if somebody recognizes it.