Atari Edge Connectors: Copper tape repair vs. Test lugs

Yoeddy

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Hey guys,

A few years ago, I bought a Dig Dug cabaret that I restored, and when I got it, the ground and +5v sections of the edge connector were burnt up. The previous owner cut the ground and +5 wires on the wiring harness connector and soldered them directly to the board. As ugly as it was, some of the guys out here provided guidance to repin the wiring harness connector and repair the board areas with copper tape. Others stated that I could just put connectors on the wires and connect them directly to the test lugs on the board. Still kinda hacky, but I went with that latter, and it has been rock solid since.

IMG_2043.jpeg

My question is, other than looking hacky, are there downsides to this? To me, it seems like the test lugs are a more solid solution compared to burning up the edge on the board. Maybe I'm wrong here, but the thought has crossed my mind of going this same route with other games that have suffered burnt edges in the past.

Thoughts?

Thanks,
Jason
 
If you fix the edge connectors properly, there's no need to hack your harness up and connect to text lugs.

Just do a proper finger repair. The trick is to wrap the tape AROUND the edge, so it covers both fingers. And remove the old fingers from both sides, even if the other side is not burned. This will ensure the copper is the correct thickness on both sides, and fit into the harness connector properly.

Then you just need to keep them clean. DeOxit and fiberglass pen every 2 years. Preventative maintenance. You'll have no issues, and your cab can look and run original. No spaghetti hacks.
 
If you fix the edge connectors properly, there's no need to hack your harness up and connect to text lugs.

Just do a proper finger repair. The trick is to wrap the tape AROUND the edge, so it covers both fingers. And remove the old fingers from both sides, even if the other side is not burned. This will ensure the copper is the correct thickness on both sides, and fit into the harness connector properly.

Then you just need to keep them clean. DeOxit and fiberglass pen every 2 years. Preventative maintenance. You'll have no issues, and your cab can look and run original. No spaghetti hacks.
I tin the copper too, unless this is bad and dulls the contact. I just had boards where the edge connector ripped them up in the past. my initial copper tape jobs I just went around the old contacts. now I shoot heat into them to get them to lift with a razor blade and cut them off for all the reasons you outlined. you don't want it too thick or it'll smash the edge connector pins, which can be a problem if you sub a different board in later for whatever reason.
 
Are you really fixing the symptoms or are you fixing the problem? Laughs.

Let me explain.
So you have an pcb edge that has failed.

The 1st question you should be asking is why did this happen?

If you spend the time and effort to fix it is this a permanent fix or a temporary fix?

Because I do limit my time for my hobbies, I tend to aim my repairs towards a permanent fix.

Let us look at this edge card problem and give this klov user a permanent fix they can try.

Why did the edge of this pcb burned? Maybe a little resistant corrosion happen?
Resistance cause heat and too much heat can burn the expoy in the these old fiberglass pcb boards.

If the pcb got hot enough to burn, the heat has effected the spring tension of that pin. Replacement of that pin recommended. I have seen failure of the edge card housing before. A straight edge will show you if your edge card connector is bowing out and should be replaced.

Well are we done? Well no. Pull out the esr meter and go through the capacitors on the pcb. A drying cap resistant goes up which draws more current and too much current draw causes pcb edges to burn. If you replace the drying out and failing caps, the current draw will be lower.

Hope this helps..
 
Thanks guys. From a purist and original design perspective, I see where everybody's coming from. I understand that it's not factory, but I was more curious if there is any kind of technical advantage or disadvantage using the test lugs. I've seen videos of this same thing being done on Pole Position if I remember correctly.

Thanks,
Jason
 
I've done that hack on Pole Position before, but Pole Position is kind of a worst case scenario, it has all kinds of issues. Dig Dug is a very well designed pcb and with a clean edge connector every dig dug in the world should be able to work just fine with the original harness setup.
 
When I got the game, it was a mess. Hacks on the fuseblock wiring, corroded connectors, floating pins in the molex connectors on the power plant…all of which smoked the resistor (can't remember which one it was) on the AR2, but after cleaning it up, changing the floating pins, fuseblock connectors, etc., it's been solid as a rock for over a couple of years now. I could have repinned the edge connector harness, but I didn't…I probably didn't want to wait for parts, and wanted to get to playing it. The test lugs work.

Jason
 
My question is, other than looking hacky, are there downsides to this?
No.

Pull out the esr meter and go through the capacitors on the pcb. A drying cap resistant goes up which draws more current and too much current draw causes pcb edges to burn. If you replace the drying out and failing caps, the current draw will be lower.

There seems to be a general resistance to testing or replacing electrolytic capacitors on arcade PCBs. I get that people who started working on these boards 10, 15, or 20+ years ago consistently found that the ecaps were fine at that time. I also get that replacing caps 'unnecessarily' can introduce problems, that it is unnecessary 'extra work,' and that 'they used quality caps' when they built these boards.

The electrolytic caps on boards from the 80s are now minimally 35 to 45 years old and beyond the expected life of the part. If you have to work on a board for some reason I wouldnt hesitate to replace them. I wouldnt bother to test ecaps of that age, I'd replace with a new cap. ( I would test the replacement caps before installation BTW, at the required power.) If there's a power issue like burned pins and an ecap in the path (like lots of the 70s PCBs that had regulators onboard) Id replace it 100% of the time.
 
If it was my board I would probably try something like this. I love this guys videos he does a lot of stuff the way I was taught but explains it 10x better than I ever could

 
There isn't really much of a reason not to use the test lugs besides purist complaints. I fix my edge connectors but I won't shit on those who don't want to.
 
I'd probably label them. Since both connectors are the same, if you transpose them the magic smoke will come out fast.

Or at least label one.

Yes, it's hacky, but there is no downside. The connector will work as installed. Electricity flows.
 
If it has already been done by the previous owner then there's no point (if you only care about functionality).
 
This reminds me that my Missile Command has the power soldered directly from the harness to the PCB, with a male/female connector to make it possible to remove the PCB without tools. It's been that way since I got it 20 years ago, and TBH, I completely forget about it except every 10+ years when I need to open it for some reason. Then I think about fixing it right for about 3 seconds, close the game, and forget about it for another 10+ years.

Only concern I'd have is about connecting to the wrong place or swapping them.

But sometimes I get satisfaction by reverting hacks like this. So I sometimes clean things up.
 
If it works, leave it alone unless it really bothers you but it looks pretty clean and I would probably put it on the list of "maybe someday". Stuff like this you go messing with and it turns to a headache sometimes.
 
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