Mac Classic

[bigeasy_uk]

Hi all,

I'm really excited, my Mac Classic will be arriving tomorrow

It's not turning on at the mo, but looks in good condition. Only cost me £21 though.

Once I get it open I can see what's wrong with it, hopefully just needs caps replacing.

If I can't fix it then I'm going to mod it and put a mac mini inside it!

 

[tevion5]

That is uncanny! A woman just shipped a malfunctioning Mac Classsic to me for the cost of shipping, roughly £20!

It's just been sent off today. Hopefully we both get these puppies up and running!

 

[bigeasy_uk]

It arrived safe and well this morning! I opened it up and had a look at the caps, they pass a visual inspection, but then I look down at the logic board and see the corrosion! damnit!

Looks like liquid damage, not something I've tried to repair before.

Any ideas anyone?

 

[Katakefalos]

Hi bigeasy_uk
Show us some photos of the damaged logic board.I had the same problem with mine and finally bought a new logic board from E-Bay.Battery killed the previous.
Also maybe you can try the trick with dish washer http://www.youtube.com/watch?v=idnD9DHFUic

Good Luck.

 

[bigeasy_uk]

Hi Katakefalos,

Thanks for the tip, I'm gonna try it tonight!

 

[Katakefalos]

Hi again bigeasy_uk
Please let the logic board dry very well after washing.
Im very anxious to see how it will go.
Good luck.

 

[bigeasy_uk]

Unfortunately washing the board has done nothing to help, although it does look a lot shinier now!

I'm not sure if it might be a power problem, I'm going to take the other board out later and have a proper look, although I'm not sure what I'm even looking for!

I've never worked on one of these machines so I don't know where to start!

 

[bigeasy_uk]

I'm thinking it is definitely a power issue now, I just tried to discharge the crt and nothing happened, so I don't think power is getting through.

Although does anyone know how long a crt can be plugged in for before it builds up a charge? It's only been plugged in for 10 mins.

 

[Katakefalos]

Hi,

Maybe some expert technician must see the power failure problem

 

[bigeasy_uk]

The component side of the analog board looks brand new, not even dusty!
There are a few yellowy-brown spots on the other side, but i think that is just the lacquer. It comes off very easily when I scratch it with a stanley knife blade, and where it is over copper, the copper looks very clean with no signs of corrosion.

 

[Katakefalos]

Try different power plug cable.Also inside there is a heat fan (mine is made by Canon) that must start spinning.
Too bad that is dead but don't worry it can be fixed. Other people here in this forum can advise you better.

 

[bigeasy_uk]

We have progress!

 

[Katakefalos]

Try to Google the error numbers and you will find the possible problem.

 

[tdiaz]

The CRT is lighting up. ;-)

That is -NOT- the problem.

It is absolutely possible to discharge a CRT and not hear anything.

As for "how long it takes?" .. you say it's been plugged in for 10 minutes? ;-)

It happened before your finger let go of the power switch. I'd say you waited long enough.

This is either a ROM or RAM issue. Since the photo is just ever so slightly blurry that making it out is just not possible .. and that the Classic has RAM onboard, makes changing out all the RAM a little challenging.. you can start by yanking the RAM card.

If it's onboard RAM/ROM, you're kind of sunk.

 

[bigeasy_uk]

Hi Tdiaz,

Thanks for your input.

The error code given is 00000003, which indicates an error in ram bank b.
It came with a ram card with an additional 1mb onboard, so I might look at a transplant, but I'm not sure my soldering skills are up to the challenge.

I'm used to discharging arcade machine crt's, which is why I was expecting a bit more of a bang!

 

[Katakefalos]

You can pull out the extra 1 MB RAM and start again like this to see what is happening.

 

[MacTech68]

How did you manage to get it going? IE showing the error?

If you leave the machine switched on for 30 mins then turn it off and then on immediately, then I'd suggest that the surface mount electrolytic caps need replacing. When these begin to fail, a gently warming makes then work.

 

[bigeasy_uk]

I've pulled the extra 1mb already, but it's the onboard ram that's faulty sadly.

I'm not sure exactly what got it going again, I'd just put the analog board back in, but I think the power connection wasn't right because it started after I gave it a wiggle (technical term).