fozztexx

fozztexx, 11 days ago

Sure glad the service manual is available on the internet. This thing is going to be complicated to take apart.

fozztexx, 11 days ago

Keyboard detached. RAM lives under it. Looks like there’s room for 4 more modules. No doubt something proprietary.

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fozztexx, 11 days ago

Oh no. The service manual says the only way to get to the power supply is to remove the screen. To remove the screen you have to peel off the sticker which is the label for the LEDs. That’s not going to be reversible. 🥺

fozztexx, 11 days ago

Well either the manuals is wrong or someone else has been in it before and didn’t put those screws back. I only had to remove the top two screws and didn’t have to permanently destroy the sticker.

fozztexx, 11 days ago

Screen removed. Putting it in the drawer to keep it safe.

fozztexx, 11 days ago

At last I have reached the power supply! It’s got an ordinary 3.5” hard drive in it. And is that a AA battery?

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fozztexx, 10 days ago

Power supply on the bench. Won’t come up if there's any kind of load on the +5V. If I disconnect the +5V and turn it on it will start. The +12V, -12V, and -5V are sort of ok, but the +5V is reading +8V! If I stick on a load after it's started sometimes it shuts down, sometimes it keeps going. With my variable load I can creep up and it keeps running but the +5V remains well over 7 volts. Kind of way in over my head on this, no idea how to repair power supplies. Especially with no schematic!

fozztexx, 10 days ago

Since I have no clue how to fix the power supply, it seems like the next thing to do is see if I can power up the motherboard. I know myself well enough to know better than to just stick wires onto the pins. I’ll bump the wires and end up shorting something out. The connector is an 8 pin 0.156” pitch. Need to dig around and see if I can find something that will fit.

fozztexx, 10 days ago

I don’t have an 8 pin, but I do have some 6 and 2 pin connectors. But they are a slightly different style with a big hook and don’t quite fit. But if I cut the hook off it drops right in.

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fozztexx, 10 days ago

That should be safe enough. Now to make the wiring harness.

fozztexx, 10 days ago

First thing to do to make a wire harness is to get some wire. I wonder if I have any. Keep hoping someday a someone will organize this better for me.

fozztexx, 10 days ago

Next I need to put pins on.

fozztexx, 10 days ago

And then stick them in the housing. Color coded same as the original.

fozztexx, 10 days ago

Banana plugs on the other end, color coded to match power supply colors.

fozztexx, 10 days ago

Everything hooked up, fingers crossed I don’t blow something up and make it worse!

fozztexx, 10 days ago

It’s alive!

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fozztexx, 10 days ago

Guess I need to get the keyboard connected.

fozztexx, 10 days ago

5 megs of RAM!

fozztexx, 10 days ago

It booted! But it keeps randomly rebooting.

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fozztexx, 9 days ago

Since the motherboard seems to work (other than random reboots) going to come back to the power supply. Not that I really learned anything about power supply repair in the last day, just going to have to try to work through using the little knowledge I have.

Since it refuses to come up, there must be something on the output side that’s overloading it. Taking a closer look it, looks like there might be some leaky capacitors.

fozztexx, 9 days ago

Oof, strong fishy smell.

fozztexx, 9 days ago

Yah that’s not right. Supposed to be 1000uF and it’s 500.

fozztexx, 9 days ago

Leaky under there too. Seems to be close to what it should be though.

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fozztexx, 9 days ago

@moira Doesn't really matter, it leaked. Not going to re-use it.