Centipede bench - LCD

Eclipse860

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I know there have been a lot of posts regarding RGB to VGA conversion but I cannot find an answer to my issue.

The scenario.. I am refurbishing a cabinet that did not have a PCB. The PCB I purchased is supposed to be full functional. I want to confirm video output before I start troubleshooting/repair the CRT and electronics. The CRT currently has very bad output.

I bought the GBS8200 and have it wired to PCB using the Component sync on Pin12. I have a "workable" image but it is all blocky. Edges and details are not proper. I have not seen any posts regarding this type of issue. I have to assume the PCB is not at fault but I currently dont have a way to confirm this.

Thoughts?
 

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I know there have been a lot of posts regarding RGB to VGA conversion but I cannot find an answer to my issue.

The scenario.. I am refurbishing a cabinet that did not have a PCB. The PCB I purchased is supposed to be full functional. I want to confirm video output before I start troubleshooting/repair the CRT and electronics. The CRT currently has very bad output.

I bought the GBS8200 and have it wired to PCB using the Component sync on Pin12. I have a "workable" image but it is all blocky. Edges and details are not proper. I have not seen any posts regarding this type of issue. I have to assume the PCB is not at fault but I currently dont have a way to confirm this.

Thoughts?
that looks like a game board issue. wait for an Atari expert to respond.
 
All the buttons work properly in game play or test mode. Game plays, all the elements appear to be on the screen (Spider, Shrooms, Player, centipede). I will read that repair log. Honestly, for now, if it comes down to the PCB, I will be working with the eBay seller on a refund/replacement.
 
No tones. Player button does audibly beep when pressed. I don't have any recourse for exchange on the eBay board. He did send a picture of the game running right before it was shipped. I think I am going to try a different RGB to VGA card first since it is cheap and returnable. Then I will focus on CRT electronics repair.. then move onto T-shooting the PCB. Goofy as it may sound I think tshooting the PCB might be fun. Love all the videos posted to help.
 
Does look like a game board issue, but weird things can happen if voltages are not good. On a bench setup I'm guessing that is good but still worth measuring on the board. The other thing you can do is reseat socketed chips. But it sounds like you either need to repair it or send it back.
 
Don't buy boards on ebay. Buy or have boards repaired here, from sellers and repair folks who warranty their work.

These boards can work when someone powers them up the first time after they've been sitting in a warehouse for 20 years, and they can crap out during shipping from them to you. That's why it's important to know the history of any board, and only buy boards that have been sufficiently burn-in tested (which is not anything on ebay).

That looks like a game board issue, but unless you've verified your setup with a known-good board, you won't be able to be sure. (I have no experience with the Gonbes converter, so I don't know how they behave with Centipedes. Maybe @lilypad19 knows.

What is the monitor doing? You may be better off repairing the monitor first, then seeing how the board looks on it. If the game board is actually outputting a yellow background, you should be able to tell that on even a partially-working monitor.

What model is the monitor, and what problems does it have? Get a cap kit, and start reading threads about that model. Monitors are generally easier to fix than game boards, and most of them aren't that bad.
 
Hard to tell... Colors could be your adapter.. In test mode you (download the manual).. you can rotate through foreground and background colors in test.. If the blocks are maintained through all of that.. there is a board issue.. vs. the foreground and background colors just happen to be the same because of the adapter
Blocks could be as simple as a bad ROM or one that needs to be reseated..

1721743688074.png
 
Yes, I should have done more research on where to buy a board. I got my two cabinets and was super excited to dive in and rushed through the purchase. I did make sure to get my voltages on the PS and the AR with help from some other posts. I spent this morning reading up on the GO7 that I have, the cap kit, flywheel, etc. and have some parts queued up ready to order. It's hard to explain what the CRT looks like without posting a picture. Best I can say is garbage and not recognizable in any way. It does at least power on. I did run through the test mode on the PCB and recall they did not flip the colors as they should. Out of test mode and in attract? mode , it does cycle through colors. I am on vacation until this weekend and will post pics when I get back as well as go though all your comments in detail. I appreciate all the posts and thoughts. You guys rock!
 
Pics of CRT. You can still see the solid background colors with no black while in game mode. In Test mode, Pressing Player 1 start button 16+ times does not change the background color at all. Only audible beeps. I am going to reseat ROM and see where that gets me.
 

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Take a look on the CRT chassis and adjust the H Hold potentiometer, that should clear the picture.

p
 
Yes, the Horizontal frequency needed adjusted and picture snapped into place! Had to also adjust the Flyback and it looks super awesome now!

Thanks everyone!
 
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