Caps trouble?

Greetings Oracle,

I hooked up my (until now perfectly working) a600 today, and the sound has gone low and crackling, and the joystick seems to be stuck up/left.

• Both failures occured at the same time.
• I have done no configuration changes to the machine
• Specs: A600 R1.5 with A601, CF card and 2mb PCMCIA SRAM
• Mouse still works, joystick tested ok in a1200

So I opened the case and found this war zone:

http://s4.postimage.org/1vitnp5d0/a600caps.jpghttp://s3.postimage.org/92c7jfyc/a600caps2.jpg

I don't know which caps are for what, but assume some of that mess explains the audio trouble.

• Do you know if any of this is causing the joystick problem as well?
• From the pictures, is there any damage not fixable by cleaning and replacing caps?

In any case, I intend to order full capacitor sets for my a600, a1200 and cd32 shortly, to avoid further havoc.

Thanks!

Hiyas

Did a quick over view for you.

Code:

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Capacitors that need replacing

[C460] 10  uf 35a
[C459] 22  uf 35v *
[C409] 100 uf 22v

[C304] 22 uf 35v
[C202[ 22 uf 35v

*- please show some caution with the heat as I suspect the pad is damaged!

Others I would replace

Q230 [ 2N9304 ]
Q231 [ 2N9304 ]

R231A [ 102 ] * 1K
R232A [ 333 ] * 33k

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Also I would -

Code:

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Check these out

[C307] 470uf - (25 - 35v)

[C305] 22uf - ( 25 - 35v)
[C304] 22uf - ( 25 - 35v)

[C821] 47 uf - (25 - 35v)
[C822] 47 uf - (25 - 35v)

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But before all that... get this motherboard in a dish washer on 50c and stop it before the drying cycle... - dont put any washing tabs / detergent in it.

let the unit air dry for a couple of hours and then remove the offending nasties =)

Thanks a lot Zetr0!

I think will have them all replaced, will try to find a local service electrician next week to do it for all three machines.
Just tried without the A601, as I found some threads where people thought it was related to an A603, but it had no effect.

However, do you think the joystick problem is due to the caps as well? The IC's seem to be fine.

I am quite sure that the joystick problems are based on badly fluctuating power, I am surprised this didn't show up with the mouse either.

good luck on getting this little bit of early 90's history repaired..... hard to believe there nearly 20 years old!

Quote:

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... and the joystick seems to be stuck up/left....

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I had the same problem with an A600.. It was the freakin PSU!, some of the voltage was less than normal... I don't remember now, but when I put another PSU the problem solved!

Chris

Thanks again guys,

Tried with three PSUs, 2,5A, 3A and 4,5A, same joystick problem with all of them. (and mouse always works)
I don't know if it's worth even fixing the caps if the joystick problem is unrelated as the a600's only purpose is gaming anyway.

Is there any chance the caps are to blame for the joystick problem as well?

yes.

you have seriously fluctuationg power, a lot of dead / half dead capacitors - no matter how clean / good the PSU is, you will be introducing burst and noise due to dying caps.

Also.. could be Paula... (controls the joystick) ?

Ok, excellent! Amiga in dishwasher, caps ordered from Cosmos :)

Update
Caps have now been replaced (by Cosmos).
The sound is now even worse (can barely hear the audio in all the noise/static)
The joystick now moves left, not up/left like before.
Joystick right input is registered, up and down are not registered.

Tested with different PSU's and joysticks.

Any other suggestions?