Motherboard No Sound

[chacal231077]

Hi! So here I have a Motherboard that has sound problems .
Before I had sound and one day nothing .
I have to turn on the sound to hear the game music slightly with a death breath Amplifier change brand new, sound wheel change new, and full nichicon FW audio Capkit for sound, always nothing .
Can be the UPD6379A dead or the UPC844C
Thanks for your help .

 

[GC8TECH]

The sound DSP gets its voltage from a seprite 5V regulator sitting on the 12V rail. IF the 5V reg isn't working... you won't get any sound.

I would start there and make sure the chips have 5V from the regulator.

 

[Kavas]

Recently had a board with no sound. I re-flowed the capacitors and it came back to life.

 

[chacal231077]

The sound DSP gets its voltage from a seprite 5V regulator sitting on the 12V rail. IF the 5V reg isn't working... you won't get any sound.

I would start there and make sure the chips have 5V from the regulator.

The 78L05

I just changed it it doesn't change anything

you take or measure the 5V on the motherboard
Thank you

 

[GC8TECH]

Here are the points to probe. Make sure all 3 terminals are OK.


Yes just like a 7805.

 

[chacal231077]

Here are the points to probe. Make sure all 3 terminals are OK.


Yes just like a 7805.

I measured +5V and +11,7v .

 

[GC8TECH]

Try This.... Use a CRO OR a good set of Head Phones etc....

Right CH, GND, Left CH.

IF you have sound here.... Then the DSP and the WAVE FONT chips are working.

 

[chacal231077]

I made the assembly with a jack connector.And I heard the music boot of the motherboard, the sound effects of the bios menu but with crackling sound exploded your ears.
The sound and even low increase the volume wheel ,exactly like on the loudspeaker of the cab the sound at low volume a whisper.

 

[GC8TECH]

I'm a little confused. Did you say you do have OK audio at the DIP chip?? OR you have audio there but its distorted??

If you are still not getting good sound there.... There is only the DSP and Sound Font Chip left.

 

[chacal231077]

The test with the headphone and the same as the test without.


I have to push the volume of the New Net city to the maximum

and the sound wheel of the Motherboard to the Maximum to hear the music of the game at a very low level with breath on it.