Please help! Shadow Force with no sound and smoke from PCB :(

[Yami]

Hi,
I just connected Shadow Force (Japanese board) to my supergun, I don't know if it was my fault (the audio switch on my Smallcab supergun was set to "Stereo") or if it would happen the same, however after few seconds from powering on, there was stink and smoke from the piece below marked as TR4:

...and now I have no sound in game (for the rest it seems working normally).

Maybe it is fixable? Voltage should be OK, what did I do wrong?

Damn, it was one of my fav titles... I'm very angry with myself.

 

[yavuzg]

Shit happens sometimes...

The burned part is a transistor and you can probably replace it easily. The big IC close to them is the mask rom containing the sound samples. If it is damaged it can also be replaced by an 27c040 eprom (burned with proper data from MAME ofcourse). But before diving into too much, you have to check if you hear any "hisss" or "crack" when you play with the volume pot or tapping the capacitors around the sound section, just to see if the problem is related with the analog parts or the digital ones...

If the burned transistor is shorted you have to remove it and test your voltages because if it is shorted and left as shorted it will continue to short the power supply -5V and you won't be hearing ANY sound. May be after just removing that transistor you'll realize that you only lost a channel or music or sound effects.

If that would be the case, then just simply put a new one in its place...

Good luck...

 

[Yami]

The burned part is a transistor and you can probably replace it easily...

Hi and thank you very much for your support.

Maybe it is a stupid question, but how can I know the exact type of transistor? Thanks

 

[yavuzg]

The burned part is a transistor and you can probably replace it easily...

Hi and thank you very much for your support.
Maybe it is a stupid question, but how can I know the exact type of transistor? Thanks

I can see from your photo that it is a 2SC1162, a standard amplifier transistor. Here is the datasheet => http://pdf.datasheetcatalog.com/datasheet/HitachiSemiconductor/mXwuvxz.pdf

But my eyes are not as good as they were so I suggest to make sure, check the markings on it by yourself. If the markings are burned as well then there are 3 more neighbors next to it, just read the markings from the neighbor