Atari 130XE yellow screen issue

[flashjazzcat]

Some pins under the OS ROM socket are barely soldered?

[runstop]

Yeah, you're right.. i did a crappy solder job there. I just re-flowed all the sockets I added. Still looks like there's an issue with D0. I bodged the antic, sally and U9 Pin 2 together, but still not getting anything. 

[TZJB]

4 hours ago, runstop said:

Here is the board. Maybe something stands out?

 

The continuity of D0 at Sally is probably under the socket as the trace seems to be on the component side.

 

Also removal of the right hand bank of DRAM would be advisable while you are faulting to eliminate any interference.

 

You haven't confirmed whether continuity of D0 is also to GTIA, POKEY, OS ROM and the BASIC ROM?

[runstop]

Hey everyone! I'm back  and I've made some progress here.. I ended up bodging D0 on the Sally and Antic and I found a bridged solder joint (from when I was swapping chips). My Sys-check II now reports everything as working (AWESOME). I even bank swapped the ram over so sys-check could test the other side and those all test fine now as well. OS Rom checksum also gets an ok. 

 

However, the system now boots to a garbled screen and no cartridge will start (I only have pacman and basic at the moment). Carts show a black screen and the basic screen is garbled (see attached). I feel like there's still something wrong with the GTIA (even though I did try swapping it before. I'll do that again here today). Anything obvious I'm missing?

 

Thanks again for all your help! You guys are awesome. 

 

 

[TZJB]

1 hour ago, runstop said:

Hey everyone! I'm back  and I've made some progress here.. I ended up bodging D0 on the Sally and Antic and I found a bridged solder joint (from when I was swapping chips). My Sys-check II now reports everything as working (AWESOME). I even bank swapped the ram over so sys-check could test the other side and those all test fine now as well. OS Rom checksum also gets an ok. 

 

However, the system now boots to a garbled screen and no cartridge will start (I only have pacman and basic at the moment). Carts show a black screen and the basic screen is garbled (see attached). I feel like there's still something wrong with the GTIA (even though I did try swapping it before. I'll do that again here today). Anything obvious I'm missing?

 

Thanks again for all your help! You guys are awesome. 

 

 

 

It's no longer yellow, but that looks nasty. What input are you using to the monitor?

 

If it's composite you may have a modulator problem, although if you suspect GTIA you may have some other continuity problems in the video circuitry.

 

You may want to continuity check the GTIA video pins to U20 the 4050, to me that looks like GTIA pins 22-25 & 31.

 

 

 

 

 

[runstop]

Yeah, sorry the picture looks awful, but I'm using the luma/chroma input on this c1702. Looks really good in person.. except it's not a basic prompt and whatever text it's trying to show is garbled. I'll check out the pins on the GTIA tonight and let you know!

 

Cheers and thanks!