A600 motherboard caps replaced audio still a problem...

AmiNeo

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Hey guys, i have just had caps replaced on an A600 motherboard due to the distorted sound you get when theyre failing and after replacing the caps, the sound problem still exists, no better, no worse...

I've check my audio equipment and thats all fine, is there anything besides capacitors that can cause this common problem?
 

Zetr0

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have you checked the voltage on the -12 (negative 12volts) ?

-12v is critical to the sound circuit.

its possible that you have some interference as well from the some other components, I will hit some schematics when I get a lul-moment.
 

AmiNeo

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have you checked the voltage on the -12 (negative 12volts) ?

-12v is critical to the sound circuit.

its possible that you have some interference as well from the some other components, I will hit some schematics when I get a lul-moment.


Thanks. Could a bad psu cause this to varying degrees on different boards? I have only one psu but a couple of different boards ive had both of which reported working fine before getting to me have had this problem to diferent degrees.

Which caps in the power inlet area would most likely affect this if the psu is good?
 

Zetr0

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A bad PSU can drastically effect all areas of the Amiga, the most sensative is the audio circuit.

to know the problem exists is to get hold of a multimeter and test the PSU static (without it pluged into the Amiga just turned on) and then under load (i.e. plugged into the miggy)

from this you will know if the -12volts is the problem of the Amiga or the PSU.

from here I can advise you better, I need to hit the schems though so bare with me.
 

AmiNeo

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Ok, i have a multimeter on the way, so that should give you a bit of time.

Thanks Z, I appreciate the help.
 

AmiNeo

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Just been fiddling again and im almost certain its down to bad connections / bad joints in the power area... Whats the best way to clean the solder pads?
 

Zetr0

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flux for soldering =)
IPA or simialr for cleanup =)
 

Zetr0

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, I will hit some schematics when I get a lul-moment.


Here in Holland we do other things as we have such moment :D


Indeed I have rented many of said videos of dutch lul-moments....

Alas I am married and as such that sort of thing doens't happen anymore =D lol



yes.... i am talking about cake baking.... whats it to ya?
 

Mad_Cat_jr

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, I will hit some schematics when I get a lul-moment.


Here in Holland we do other things as we have such moment :D


Indeed I have rented many of said videos of dutch lul-moments....

Alas I am married and as such that sort of thing doens't happen anymore =D lol



yes.... i am talking about cake baking.... whats it to ya?

Yup, cake that is, with Kim Holland and friends.
 

AmiNeo

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, I will hit some schematics when I get a lul-moment.


Here in Holland we do other things as we have such moment :D


Indeed I have rented many of said videos of dutch lul-moments....

Alas I am married and as such that sort of thing doens't happen anymore =D lol



yes.... i am talking about cake baking.... whats it to ya?


Cake baking? Not dough making then? u know the kind that gets a bun in the oven? :LOL:

---------- Post added at 15:50 ---------- Previous post was at 15:45 ----------

flux for soldering =)
IPA or simialr for cleanup =)

IPA as in Isopropanol alcohol? Cool, will have to restock...
 
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AmiNeo

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Ok its obvious I now need a good PSU for testing once i get a chance... What are my options?

Im guessing buying another amiga one may be dodgey since theres no way to tell if that one too is weakening,

As for the PC PSU hack, I would need to buy a pc psu to try it... anyone selling one already done?
 

Zetr0

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I might be able to help you with that AmiNeo,

I just need to have some Chin waggery with a cheeky Chiark =D
 
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