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Duo 230 pickup..
Posted by: imactheknife on 2023-10-16 18:44:20
So, i grabbed a couple of cheap duo 230 units. One showed up today, so tore right into it. I did notice some blotches on screen that i didnt or couldnt see in the listing. I recapped both logic board and screen.

I did turn it on before recap and it turned on, chimed, but would shut off during boot process.

After recap, screen works, although still has blotches (lcd rot??)

The logic board still turns off during boot, any ideas??

I have another duo 230 logic that is recapped so i am using that for now..
Posted by: 3lectr1cPPC on 2023-10-16 18:56:42
That damage is usually caused by pressure. Not sure if “LCD Rot” looks the same or not.
Posted by: imactheknife on 2023-10-16 19:02:03
That damage is usually caused by pressure. Not sure if “LCD Rot” looks the same or not.
Yeah, its weird!! Well, at least it works lol.. hope that other one isnt like that. Have a 280c coming too
Posted by: joshc on 2023-10-17 01:56:51
The logic board still turns off during boot, any ideas??
Marginal power supply?
Posted by: mdeverhart on 2023-10-17 05:51:23
Marginal power supply would be my guess too. Do you have a video of it shutting down while booting?

Do you have a PB 1400, 3400, or G3 (any generation)? The power supplies for those machines will work with a Duo:

https://68kmla.org/bb/index.php?threads/power-supply-for-powerbook-duo.42577/post-462610
Posted by: imactheknife on 2023-10-17 06:00:37
Marginal power supply?
Got it to work. So both logic boards working. What chip would take care of mouse/ trackball?
Posted by: imactheknife on 2023-10-17 06:02:02
Marginal power supply would be my guess too. Do you have a video of it shutting down while booting?

Do you have a PB 1400, 3400, or G3 (any generation)? The power supplies for those machines will work with a Duo:

https://68kmla.org/bb/index.php?threads/power-supply-for-powerbook-duo.42577/post-462610
Yeah, i have 20 yoyo adaptors for my clamshell ibooks, so those will work? The power adapters are working fine. I got board working.
Posted by: mdeverhart on 2023-10-17 07:12:18
My understanding is yes, the YoYo will work:

https://68kmla.org/bb/index.php?threads/pin-out-m7783-power-supply-duo-230.40402/post-437210

I’ve not personally tried it.
Posted by: mdeverhart on 2023-10-17 07:12:49
I got board working.
How did you solve the issue with the board shutting down? Just curious for future information.
Posted by: imactheknife on 2023-10-19 07:28:31
How did you solve the issue with the board shutting down? Just curious for future information.
The board with issue works fine outside of the case, but still does the shut down during bootup inside of case, weird lol. So i am just keeping other logic board in that one for now.

My second duo 230 showed up and screen is mint🙂 so that’s good news..
Posted by: imactheknife on 2023-10-20 19:01:46
So, both keyboard have dead keys. I imagine this is a common issue? I tried cleaning contacts, no change really. Unless someone has fix?
Posted by: 3lectr1cPPC on 2023-10-20 19:15:24
@techknight
Posted by: mdeverhart on 2023-10-20 19:20:29
Did you pull off all of the key caps and take the plastic layers apart so you could clean the contacts? Gently cleaning the contacts with an eraser can help. The other thing to look for is broken traces on the plastic layers. My 230 had a couple of breaks that led to dead keys. You can carefully use some conductive paint to repair the traces.
Posted by: imactheknife on 2023-10-20 20:20:14
Did you pull off all of the key caps and take the plastic layers apart so you could clean the contacts? Gently cleaning the contacts with an eraser can help. The other thing to look for is broken traces on the plastic layers. My 230 had a couple of breaks that led to dead keys. You can carefully use some conductive paint to repair the traces.
Cool, will definitely try this! Thanks for the tip🙂
Posted by: mdeverhart on 2023-10-20 21:47:26
No problem! Be careful - the plastic wrinkles easily. Look for dark spots (corrosion) on the traces or obvious breaks. I think I used a multimeter in continuity mode to check suspect traces. The conductive paint can also remove the existing good traces from the plastic, so just try to bridge any gaps and don’t wipe off any excess (and make sure you don’t bridge two traces!). I had to do some touch-up after I inadvertently removed some good trace lines.
Posted by: Solvalou on 2023-10-24 18:12:06
I have the same issue with my 230. I had a 210 which I swapped the displays over though that too had the same problem just to a lesser extent. I can put up with mine but it is right in the middle of the screen pretty much. Would have been happier had it been more like yours that was on the edges but since they're pretty rare here in the UK, I will take what I can get, at least it boots fine I suppose!

Regardless, glad you found a replacement that is fault free. I'm guessing this is a real problem with Duo displays, perhaps being a lot thinner (than the standard PowerBooks) the display is probably more fragile and susceptible to pressure.
Posted by: 3lectr1cPPC on 2023-10-24 18:13:16
I believe so too - I'd imagine seeing it around the edges would be a sign of something heavy being set on top of it for a long time.
In the upper middle center would likely be from the trackball.
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