Search results

According to my notes, DBLite was the codename for the PowerBook Duo 210/230, not the 160/165. But I think all four share the same driver: '.Display_Video_Apple_DBLite'. The PowerBook Duo Prototype Schematics have recently been released and they feature the GSC chip, in case that's of interest.

Looks like they've been released: https://tinkerdifferent.com/resources/macintosh-powerbook-duo-prototype-schematics.176/

I’ve got two original power supplies that’ve been recapped and they seem to be holding up quite well.

Is that a custom design to Apple spec, or off the shelf?

So how did you go from not successful to successful? What was the issue?

Yes, thought so - Its a Rev 3. If you have any graphical anomalies you’ll need to do the bodge wire across the PAL chips.

Rev 3 board?

Makes sense - so greyscale is not really a ‘feature’ of these panels, it’s just how it’s being driven by GSC. Does the active matrix panel also use dithering to generate greys? I’m guessing not, but…

Now that I have a 100MHz PPC card I did some benches in Norton System Info. I was indeed right about this, but what’s interesting is that this machine’s lower score is actually on a par with the Duo 2300c. Of course we know that these PPC upgrades share a ROM with the 2300c and that’s going to...

Makes sense to see if cooling helps first. But is it the 040 that needs active cooling, or the memory controller? (Maybe both…) It would be good to try sticking a heatsink on the latter but with it facing down against the logic board there really isn’t an easy way to do that.

At 40MHz I can’t get any of my CPU cards (I’ve tried about 3) to pass more than 2 runs of MacBench’s graphics test without dying, and that’s only with 36MB RAM. With 20MB RAM there’s no problem, so the memory controller evidently has to work harder with more banks activated. I absolutely did not...

lack of adb is unforgivable!

It tends to be the logic board and the analog board that need plenty of attention. I've never had any issues from the power supplies, though I've only ever seen the Sony units. Things get 'interesting' again when you start adding in PDS cards.

I do repairs for people from time to time and have so far have yet to deal with anyone problematic. The day I do I hope it doesn’t sour things because most people Ive encountered in the hobby are patient and respectful.

Yeah I'd grab whatever data you can off it that you want to archive and consider the drive 'done'.

Pretty sure I’ve seen a LM64P512 as well.

I entered the hobby in 2022 with an SE/30 and it took me two years to get it running properly. So this is accurate.

The one Mac in particular that I enjoy running at stock speed is the SE/30. Maintaining one running reliably is sufficient enough of a challenge.

They should just be 100nf caps? Nothing special. I’d suspect either the cache chips themselves or the solder work :LOL:

Google ‘stiction’ - the heads can be stuck to the surface of the platters preventing them from moving, which is different from the actuator being stuck to a sticky rubber bumper