Atari 2600 Heavy Sixer Graphical Issues

[Ianr757]

Hey guys, sorry to post so many threads here recently. I'm on the (hopefully) last of my recent batch of 8 heavy sixers, and this last guy is the worst so far. When it turns on, which is almost never, the screen looks terrible and the graphics are often glitchy. For instance, the barrels in Donkey Kong don't even roll where they are supposed to and sometimes just roll in place. I've recapped the unit (including changing the voltage regulator), cleaned contacts with alcohol and deoxit, swapped in and out like 3 different chip sets, tried a different power supply, but nothing. I know it is a main PCB issue because I've swapped the switch board as well, making no difference. I'm not sure if the trace on the back of the board (shown in the close up picture) makes any difference, but I've decided to include it just in case. Please help me guys. I'm at a total loss.

[Skwrl63]

I had a similar issue with my 4-switch model. Some games would work (picture seemed clear, however still really glitchy/un-playable game play). While most other games wouldn't give me a good picture at all (just some frozen colored screen).

 

It ended up just being a bad Riot Chip. After replacing the Riot Chip everything worked great.

 

But I see that you stated you already tried multiple chip sets, so I really can't offer any advice. Good luck

[Ianr757]

8 hours ago, Skwrl63 said:

I had a similar issue with my 4-switch model. Some games would work (picture seemed clear, however still really glitchy/un-playable game play). While most other games wouldn't give me a good picture at all (just some frozen colored screen).

 

It ended up just being a bad Riot Chip. After replacing the Riot Chip everything worked great.

 

But I see that you stated you already tried multiple chip sets, so I really can't offer any advice. Good luck

Maybe I'll try swapping just the riot a few times, see if it makes any difference. Thanks for the advice, dude.

[Ianr757]

Update: after swapping in a newly tested and working chip set, the system began working. BUT, this only lasted a few minutes if that. Then right back to black. What the hell is up with this thing?

[Voxel]

Sometimes the original chips are fine, so don't be eager to bin them they may just need the oxide/gunk removed.

 

There are two things here the chip and the socket.  Connecting surfaces on both need to be cleaned.  You can push in the chips so they are very snug and add something like Deoxit, then leave alone for a day for it to get to work. 

 

Otherwise you can remove the chips and delicately clean the pins, add some light oil (a very thin oil), then clean the sockets (you can use a toothbrush with a slight hint of oil), then insert the chips a few times and connect up.  You may need to repeat this process a few times with the chips as it rubs down the connecting surfaces to clean metal.

 

 

[Ianr757]

On 11/14/2020 at 3:45 AM, Voxel said:

Sometimes the original chips are fine, so don't be eager to bin them they may just need the oxide/gunk removed.

 

There are two things here the chip and the socket.  Connecting surfaces on both need to be cleaned.  You can push in the chips so they are very snug and add something like Deoxit, then leave alone for a day for it to get to work. 

 

Otherwise you can remove the chips and delicately clean the pins, add some light oil (a very thin oil), then clean the sockets (you can use a toothbrush with a slight hint of oil), then insert the chips a few times and connect up.  You may need to repeat this process a few times with the chips as it rubs down the connecting surfaces to clean metal.

 

 

Gave this a shot, still no dice. Any final calls before this becomes a parts machine?

[+Nathan Strum]

It's a little hard to see, but it looks like the hex buffer is still soldered (not socketed). Have you tried replacing that yet?

[Ianr757]

13 hours ago, Nathan Strum said:

It's a little hard to see, but it looks like the hex buffer is still soldered (not socketed). Have you tried replacing that yet?

I guess it's worth a try. I'll see about swapping in a replacement. Thanks.

[Ianr757]

Well, this is weird. Before I even replaced the hex buffer, some games started working (Missile Command, Coleco's DK Cart, etc) but not others (Pacman, Popeye, Berzerk). I replaced the chip and still no change from that. I should note that I have started to use a new switchboard (the other works perfectly fine in my other console so I have no idea why this would make any difference). It seems the new switch board allows certain games to work, or it could just be a total coincidence. Both boards have been recapped. Why would some games work but not others?

[+Nathan Strum]

Have you cleaned the cart slot and cart ends? Dirty contacts can cause really intermittent behavior. (I posted some cartridge slot cleaning tips in my blog.)

 

Only other suggestion I have at this point, would be changing out the voltage regulator. Console5 has them as part of their tune-up kits.

[+DrVenkman]

Do you have a logic probe or oscilloscope? You might have one or more worn out sockets, especially if you've swapped a bunch of chips as part of your troubleshooting already. The single-wipe sockets Atari used are prone to becoming bent and losing spring tension, and sometimes they get dirt and surface corrosion - hell, when I was restoring a 1200XL once, I found a socket wipe that had broken clean off; the piece was found down inside the leg hole when I replaced the socket.

[Ianr757]

2 hours ago, Nathan Strum said:

Have you cleaned the cart slot and cart ends? Dirty contacts can cause really intermittent behavior. (I posted some cartridge slot cleaning tips in my blog.)

 

Only other suggestion I have at this point, would be changing out the voltage regulator. Console5 has them as part of their tune-up kits.

I've done my best to clean with IPA and Deoxit, but nothing. I replaced the VR as part of the cap kit.

 

2 hours ago, DrVenkman said:

Do you have a logic probe or oscilloscope? You might have one or more worn out sockets, especially if you've swapped a bunch of chips as part of your troubleshooting already. The single-wipe sockets Atari used are prone to becoming bent and losing spring tension, and sometimes they get dirt and surface corrosion - hell, when I was restoring a 1200XL once, I found a socket wipe that had broken clean off; the piece was found down inside the leg hole when I replaced the socket.

I have a multimeter, but that's it. Would that be of use here?

[overgrouth]

I had a similar issue as this and it was my power switch. I had my friend desotter and sotter it back in place after he tried to argue with me that the connections looked fine.

 

I know this Sounds silly but if some of the pins are not getting good connections you can loose power and you get anominly's just as you would with low voltage.

 

Hope this helps.

 

Let me know how it turns out for you.

Edited November 19, 2020 by overgrouth

[Voxel]

I'm of the opinion that there are connectors that need cleaning.

 

As you swapped boards your findings indicated that there is a connection issue.

 

The connectors on the original pairing would mate at certain points, when you swapped boards the new pairing would see a change to the connecting points, so there was an improvement.

 

I'd suggest more work cleaning the mating surfaces, including all switches.