Another Mod Question...

[yoras]

Okay, I'm on my third mod attempt and hope that this one goes as smooth as the first and no where near the last. I used some plastic epoxy to keep the wires from pulling out the solder plates for the jumper connections.

 

Anyway, my question is... I have all my connections hooked up and I have checked, double checked and checked again correct connections and no solder bridges. Everything seems perfect but when I plug a cartridge in, I get graphical noise in the image. You can see that the game is there but there is a bunch of graphic anomalies all over the screen. It's playable, just the graphic garbage is quite annoying. This is the same problem that I had with my last unsuccessful mod attempt. My ribbon cable is less than 6.5'' long, could that be the problem? Any suggestions would be appreciated.

 

Here is a pic of it running the combat CARTRIDGE (not the built in combat) running on rev b fb2

Edited October 28, 2005 by yoras

[yoras]

My ribbon cable is less than 6.5'' long, could that be the problem?  Any suggestions would be appreciated.

 

 

955912[/snapback]

 

ok I shortened the ribbon cable down to 5'' long and resoldered the entire board and connector checking each individual connection as i went and still the same problem.. the built in games work just fine. man this sucks

 

Here are pics of video pinball and circus atari sound works just fine

Edited October 29, 2005 by yoras

[+batari]

My ribbon cable is less than 6.5'' long, could that be the problem?  Any suggestions would be appreciated.

 

 

955912[/snapback]

 

ok I shortened the ribbon cable down to 5'' long and resoldered the entire board and connector checking each individual connection as i went and still the same problem.. the built in games work just fine. man this sucks

 

Here are pics of video pinball and circus atari sound works just fine

956290[/snapback]

I'm not sure if it's the same thing, but I got some strange effects when I booted up a cart and had the J3/J9 switches set wrong and/or had bad connections to these switches. THe cart would often boot up and run, but there was garbage on the screen.

 

If I had a guess to the source of the problem, I would say that the FB2 menu mode and its associated graphics registers (which are almost certainly different from the TIA's) are being enabled at the same time the cart is running.

[Kokovec]

I'm not sure if it's the same thing, but I got some strange effects when I booted up a cart and had the J3/J9 switches set wrong and/or had bad connections to these switches. THe cart would often boot up and run, but there was garbage on the screen.

 

I would agree with that assessment.

When I performed my mod I had the same problem.

As it turned out I wired the switch incorrectly.

 

Also, you may want to make sure that you do not have a cold solder joint

Edited October 29, 2005 by Kokovec

[yoras]

Okay, I just don't get it. I got my first one going no problem, except for not paying attention to the pinout on the cartridge connector. My second one didn't go so well but it was my fault cause I accidently pulled a wire that I shouldn't have. But this third one is really destroying my confidence. I've done plenty of mods and solders and I should not be having this problem. I have quadruple checked all my connections and tested each one and it should work. I'm beginning to think that the unit is defective. It seems that J3 doesn't make a bit of difference, connected or not. I think that is where the problem is. I tried to find an alternate J3 connection but to no avail. J3's run goes under the black epoxy chip and from there, who knows? The built in games work just fine with J9 shorted even if J3 is also shorted. Hmm. I'm now hesitant to go out and buy another unit and I'm running out of ideas.

[carpecarne]

Okay, I just don't get it.  I got my first one going no problem, except for not paying attention to the pinout on the cartridge connector.  My second one didn't go so well but it was my fault cause I accidently pulled a wire that I shouldn't have.  But this third one is really destroying my confidence.  I've done plenty of mods and solders and I should not be having this problem.  I have quadruple checked all my connections and tested each one and it should work.  I'm beginning to think that the unit is defective. It seems that J3 doesn't make a bit of difference, connected or not.  I think that is where the problem is.  I tried to find an alternate J3 connection but to no avail.  J3's run goes under the black epoxy chip and from there, who knows?  The built in games work just fine with J9 shorted even if J3 is also shorted.  Hmm.  I'm now hesitant to go out and buy another unit and I'm running out of ideas.

956599[/snapback]

 

I don't know if this helps, but the RevB flashback 2s have a different layout than the RevAs. Did you follow the silkscreen on the board or according to the instructions on Curt's website?