• Hello MLAers! We've re-enabled auto-approval for accounts. If you are still waiting on account approval, please check this thread for more information.

Search results

  1. GRudolf94

    Only half of screen showing on PowerBook 100 (red solid color on rest)

    The only STN machine I have with me atm is a PB520, and that's a slightly different panel IIRC. I can have a peek later and see if I come up with anything else. Check the lower data bits just in case, but it'd be weird if they happened to be undriven. I also think there should be more voltages...
  2. GRudolf94

    Machintosh Classic II Sound Issue

    I... Think I might need counseling after seeing this.
  3. GRudolf94

    Only half of screen showing on PowerBook 100 (red solid color on rest)

    Ha, I had a recollection of already having explained how that works - and it's the thread you linked. Most likely cause is a missing bias voltage to the lower row drivers. Check continuity, and compare voltages on each pin at the top row drivers with the bottom ones. Which voltage rating did...
  4. GRudolf94

    iBook G3 Clamshell vinegar syndrome

    That should work. Your board should be fixable, too, although that'll require component-level rework, obviously.
  5. GRudolf94

    iBook G3 Clamshell vinegar syndrome

    Excuse the crudeness of the drawing - this is the best way I can visually explain this. Even though that connector is different on the newer panel, and it happens to match 180deg off, the positions in which the wires go probably didn't change. This is an oversimplification of what a display...
  6. GRudolf94

    iBook G3 Clamshell Is The Supercapacitor Required For Functioning?

    They've been leaking on 12" G4s for a while, now. I would assume older machines are all at risk. IIRC the machines where I removed them all worked fine without a replacement.
  7. GRudolf94

    iBook G3 Clamshell vinegar syndrome

    If they're both the same panel, the pins are probably in the same order, and the connector needed to be different. By installing it backwards, it's possible that you damaged the new panel, and you almost certainly made the 3.3V supply to that fail by shorting it - which is likely why you get...
  8. GRudolf94

    New theory on the cause of the infamous Tunnel Vision problem - Testers needed!

    No. It has nothing to do with adhesion. If the layers were to separate you'd have a permanently damaged display. They don't, can't and won't re-bond. This (probably) has to do with moisture dispersed in the liquid medium. Heat alone will do nothing - it is simply an aid to draw out moisture...
  9. GRudolf94

    Backlit Portable with broken display cable

    The diffuser is many layers. The acrylic panel behind those is the lightguide (and should be fine). That looks like liquid/mold damage. It's possible to buy replacements, or just salvage them from scrap LCDs. Careful handling with gloves is necessary - skin oils and any abrasion will cause...
  10. GRudolf94

    [ATTACH] I've been very lazy to finish and test my designs, but maybe now this one will be done.

    I've been very lazy to finish and test my designs, but maybe now this one will be done.
  11. GRudolf94

    Anyone has schematics for 270c and 520?

    Not only schematics but it seems a disk (and ROM?) dump too?
  12. GRudolf94

    68030 and Counterfeiting?

    The funny thing to me is that they try and make a ceramic chip look like epoxy, with that textured top. Try and wipe it with some acetone. Sometimes the original markings are still readable. It could be a 33MHz part, just an older mask.
  13. GRudolf94

    Powerbook Duo 2300c Capacitor ID

    First number called out is typically the capacitance - in this case, 33uF.
  14. GRudolf94

    While spontaneous failures are not unheard of, I'm always concerned when parts that are exposed...

    While spontaneous failures are not unheard of, I'm always concerned when parts that are exposed to the outside world fail. Do you use any external (especially mains-powered) SCSI peripherals on this machine? If you do, I'd check that those are all well-grounded, that kind of thing.
  15. GRudolf94

    GBSCSI - A cheap(er?) solution to replacement storage

    It could be the opposite like you said. I haven't looked at that datasheet in a good while. Hm. Indeed. It's a value that can be experimentally obtained, though. If I solidly characterized that value, and it met spec, then I'd have no qualms using that. Realistically since we're dealing with...
  16. GRudolf94

    GBSCSI - A cheap(er?) solution to replacement storage

    It does. Which is why this is a non-issue 99.99% of the time (and the bus can cope with the 00.01% where it isn't). That works for lots of cases, but then I'm also creating a filter on each line. I'd need to think more about the implementation. I didn't have a lot of time to think and prototype...
  17. GRudolf94

    GBSCSI - A cheap(er?) solution to replacement storage

    Thanks - I did try and pay attention to the layout, and did everything I could to keep it reasonably clean. Indeed, SCSI is supposed to be open drain, and each line must be able to sink 48mA. So I'm somewhat violating the spec twofold here - those buffers are only good for 32mA (but they can...
  18. GRudolf94

    G5 quad showing leaking caps

    Greeeeat. *sigh*, fine, I'll do it when I yank the LCS to reseal that too.
  19. GRudolf94

    GBSCSI - A cheap(er?) solution to replacement storage

    My bad, not an intentional omission - I honestly expected myself to write my own SDE code at some point, but I keep being forced to realize I am not really a SW guy.
  20. GRudolf94

    New theory on the cause of the infamous Tunnel Vision problem - Testers needed!

    The bad panels are 640*400. That limits somewhat-direct swaps. It also complicates swapping in something else - we'd need new bezels, a 1280*800 LVDS panel, and an FPGA inbetween machine and panel. Replicating any moderately big LCD is outrageously expensive - I've begun doing that for a...
Back
Top