Graphics issue with my PC engine

[biniou24]

Hello !
I'm a newcomer on this forum !  O:)
I'm 35, and already owned a pc engine, many years ago... and I recently thought that playing Soldier Blade and BC Kid again would be great.  

I'm really impressed by this forum, and the repair section: it's really huge !    
But I didn't found a topic that would help me, because it's really "special".

Here is my problem.
I bought few days ago a core grafx modified to release a RGB video. Unfortunatly, it had a "buzzz" sound, and I finally found that it was a ground problem. While I was trying to find an other blob of solder to fix to it... at the very same time, I made an unforgivable mistake, and made son pins (din port of the cable) in contact while the console was powered on.      

The screen became black and the music stopped.

I powered off the console, then powered on... and... no luck.
Graphics are almost "dead", many sprites and backgrounds are not displayed.
Note that the sound still is ok and controls seems to be ok too (I hear it when I play).

I only own 2 games.
With SCI, there is no graphics at all.
With Mr Heli, the score, life meter etc. displays well, but nothing more.

I've checked the fuse of my console, and it's still ok.

Here is a picture (in game) of Mr heli:


Do I have to kill myself ?  
What can I check ?

I have to say that few seconds before I made my mistake, the games worked fine (except for the buzzz sound, as said before), and I've plugged my console on 4 different TVs. Same problem...

Any help or advice would be really appreciated !  

[Drakon]

I wouldn't say kill yourself but your system is gone.

[biniou24]

Thanks.
Is it sure that there's now way it can be repaired ?

[Frank_fjs]

If you've done damage to the CPU or video chip then it's probably not worth repairing. Pretty cheap to grab a CoreGrafx on its own and just use the controller(s)/hook-ups from your damaged console. Re the RGB mod, shouldn't be much to get someone here to perform one for you or you could even build an external RGB box.

[biniou24]

Thank you for these advices.

I will buy another console (loose) and modify its output.
I already own a RGB cable for pc engine/core grafx.

[thesteve]

looks like you may have a solder bridge on the video chip (lots of flux and solder wick to remove excess solder)

[Drakon]

Yeah if you bridged pins and didn't unbridge them then your system will remain dead.  Years ago when working on my neo geo mvs I was getting a ram error, turned out I had dropped some solder onto the pcb and it was bridging ram pins.  Once I removed the solder the system ran fine.  I figured from your description that you only temporarily bridged something not left it bridged.

[biniou24]

Hello,
I didn't soldered anything inside the console by myself. And did not have opened it. The console already was RGB-modded.   

You guys are talking about video chip inside the console: do you think it can have bridged "itself" (due to contact between pins of the cable while powered on) ? 

PS: sorry if my english is poor and hardly understandable. English isn't my first language. 

[biniou24]

Hello again,
here are some pictures of chips inside my console.
Is there something I can check ? Are the three of them... video chips ? (or sound chips ?)

http://i39.servimg.com/u/f39/11/29/64/44/626010.jpg
http://i39.servimg.com/u/f39/11/29/64/44/627010.jpg
http://i39.servimg.com/u/f39/11/29/64/44/628010.jpg

[Drakon]

From your description it sounds like you only momentarily bridged something not soldered something together.  If nothing's bridged then your console's done.

[thesteve]

any bent pins on the expansion port?