Rescuing Amiga CD32 I need advice

j0a0

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I Bought this defective dream machine, Amiga CD32.

It has an PC AT power supply.

It works the games, the problem is in the sound.

As soon as a CD is placed, horrible and loud sounds like thunder come out of the TV speakers, the horrible sound seems rhythmic with the operation of the CD player mechanisms.

I am not prepared to replace all SMD capacitors, I do not have a soldering station, and getting SMD capacitors is very difficult here where I live.

I will leave the full recap for after I get a soldering station, which should take a while because the cost is high around here.

I need advice from which capacitors start replacing to solve this problem.
 
I Bought this defective dream machine, Amiga CD32.

It has an PC AT power supply.

It works the games, the problem is in the sound.

As soon as a CD is placed, horrible and loud sounds like thunder come out of the TV speakers, the horrible sound seems rhythmic with the operation of the CD player mechanisms.

I am not prepared to replace all SMD capacitors, I do not have a soldering station, and getting SMD capacitors is very difficult here where I live.

I will leave the full recap for after I get a soldering station, which should take a while because the cost is high around here.

I need advice from which capacitors start replacing to solve this problem.

Contrary to popular belief it's not guaranteed that replacing the audio capacitors alone will solve your problem. Often the issue is not only due to a faulty component, but caused by base (corrosive liquid leaking out of the capacitors) which corrodes copper tracks and other components on the PCB. It's impossible just point to a few components to say replace those and your problem goes away. It's like asking your car mechanic to write to you on the interenet to tell you which car components to replace when your car makes strange noises. What you need is proper diagnosis of the fault and then the actual repair, and then probably replacement of all the other capacitors to avoid future corrosion.
 
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I Bought this defective dream machine, Amiga CD32.

It has an PC AT power supply.

It works the games, the problem is in the sound.

As soon as a CD is placed, horrible and loud sounds like thunder come out of the TV speakers, the horrible sound seems rhythmic with the operation of the CD player mechanisms.

I am not prepared to replace all SMD capacitors, I do not have a soldering station, and getting SMD capacitors is very difficult here where I live.

I will leave the full recap for after I get a soldering station, which should take a while because the cost is high around here.

I need advice from which capacitors start replacing to solve this problem.

Contrary to popular belief it's not guaranteed that replacing the audio capacitors alone will solve your problem. Often the issue is not only due to a faulty component, but caused by base (corrosive liquid leaking out of the capacitors) which corrodes copper tracks and other components on the PCB. It's impossible just point to a few components to say replace those and your problem goes away. It's like asking your car mechanic to write to you on the interenet to tell you which car components to replace when your car makes strange noises. What you need is proper diagnosis of the fault and then the actual repair, and then probably replacement of all the other capacitors to avoid future corrosion.

I imagined that this defect in particular had known solution.


As in other consoles that I have, a defect like this, you ask and someone already points the culprit capacitor, like my 3DO Fz-1, had similar problem in the sound, I asked and the people pointed the capacitor to replace and solved the problem .

Even a less accurate help such as starting with the decoupling capacitors, then those of the CD controller card, finally try those of the sound of the main board, would be something for example.


Maybe someone has experience with this defect and point a capacitor that I do not even suspect could be the cause.

The symptoms even seem to help find the defective part because the sound is perfect while I do not put a disc, the intro has the sound clean and loud.
 
As above, cap replacement is not the golden fix, it could have track, pad or VIA damage, but also could have transistor damage from the leak. so take your time and good luck!
 
As above, cap replacement is not the golden fix, it could have track, pad or VIA damage, but also could have transistor damage from the leak. so take your time and good luck!

I see from your signature that you work with repairs.

Sound comes out normal until you insert a disc and strange sounds are mixed to the signal louder than the sound of the games, and appear to be the echo of the CD-Rom motor and pickup lens motor.


Have you fixed one with that defect that I described?
 
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If I remember correctly it's shortwire between ground signal of one capacitor and dac mute line under that capacitor.

Most likely C792 near DAC.

Probably some solder to be removed, or capacitor slightly moved.
 
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If I remember correctly it's shortwire between ground signal of one capacitor and dac mute line under that capacitor.

Most likely C792 near DAC. Could be also C306.
Probably some solder to be removed, or capacitor slightly moved.

Thank you very much.

I will preemptively replace capacitors c408, c811 and c821, these are easy to find here to replace.

Later this year I can buy a soldering station to do the full service, I do not want to destroy the board by removing the old ones with ordinary soldering iron.
 
A very sad day.

The video game has been messed up by somebody before.


almost all the capacitors were changed and it was very poorly done, exchanged for common capacitors, not smd.


And to make matters worse he stopped to read disks and burned a component next to the cable flat, I could not identify is an 8-legged IC.


I'm going to give it back and ask for a refund, I paid too much and it was not to be defective in the description of the sale.
 
Good luck. I'm not surprised to see a recap damaged machine. "Professional recappers" and other electrical witchdoctors have worked hard to convince everyone it must be done to working machines, so it was only a matter of time before an idiot tries to do it.
 
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Good luck. Sometimes I think I am an idiot, but at least I am able to fix all my mistakes :)
Learning from doing recap CD32 to tantalum caps is to put additional layer of pcb varnish before soldering tantals, as solid caps have wider connectors that may touch other pcb lines. It happened to me causing issue as described. Thin CD32 solder mask worked as 50Ohm resistor between DAC mute and audio ground :)

Wysłane z mojego ASUS_Z00AD przy użyciu Tapatalka
 
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