Ah, Gottlieb... the scourge of the pinball community.

Courtesy of songofsixpence in the Troubleshooting System 80 thread, here is a source:

http://www.arcadeshop.com/i/475/molex-pin-snap-in-crimp.htm

Or this source from smailskid

http://www.twistedquarter.com/index.php?main_page=product_info&cPath=177_184&products_id=1115&zenid=ndg3e69agvv5a13r6sp96hqut7

Todd's version of the ground update is frankly, a minimal approach. There's a lot more you should be doing besides adding two wires to the CPU to Driver board connector. Ground mods on gottlieb's is a huge deal, and he just takes the short cut.

In order to be able to adjust the 5V correctly, yes, many times this kind of pots has dirty inside and doesnt work correctly, like the sound pots when you try to adjust the volume and you can only find mute or maximum...

Is the correct information/process detailed anywhere?

You didn't say which System. Here is the pinwiki for System 80

http://pinwiki.com/wiki/index.php?title=Gottlieb_System_80

Go to the ground updates section 4.4

CFH and Cactus are steering you in the right direction.

On the sys80b power supply, do not spray the 5 volt adjustment pot. REPLACE the damn thing! it's like 50 cents (500 ohm pot). He's on the right track (in that this pot is failure prone), but it needs replacement, not sprayed with some chemical.

Since no one answered your original question, arcadeshop.com has the bifurcated pins used in the CPU/Driver board interconnect, assuming that's the +5V/Gnd mod you're referring to.

I beg to disagree...I have worked on more Gottlieb Pinball machines than anyone here....for 39 years. We have reconditioned several thousand of them...and once we have done our mods, they rarely fail. Of course, you are welcome to do all that extra nonsense if you desire. And then when you have to take a board out or move it to another game, remake all those silly screws and wires on the next board!

Here they are:
1. Rebuild the System 80 power supply--there are full kits out there--reheat the header pins before you put board back together. On system 80A and B, tighten the transistor screws, reflow header pins, and squirt the pot. Then burnish all the silver header pins with a fiberglass eraser. Rarely does that regulator go bad. The system 80 and 80B power supplies are very good. (However, on System 1 games, I suggest you put in a brand new power supply.)
2. On System 80 and 80A, and some 80B games...add the extra ground wire on the interconnect cable. We simply remove a wire from a "parts" connector...that way you have the exact pin premade for you! By doing this simple easy mod, the logic board now makes a firm solid ground connection to the driver board!
3. Burnish ALL the foil traces on the logic and driver boards the plugs plug into with a fiberglass eraser. Then with contact cleaner, squirt al the plugs before reconnecting.
4. On System 80A and some B games, the bottom transformer mod HAS to be done (I have a video showing how to do this)...it solves well over a dozen odd problems.
5. On logic board of system 80A and 80B hat has that little satellite board...it is loaded with cold solder connectors both on the main board and UNDER the little satellite board. We always remove them with our solder station and reheat everything...HOWEVER, this may not be possible for you if you do not have the right knowledge and equipment.
6. The early System 80 and some System 80A games need the pop bumper boards updated...its simple and doesn't require any new parts, and pretty much bulletproofs those little boards from every failing again. I have a video up on this.

IF THE BATTERY LEAKED---on either system, you may have to change the connectors below that damn battery. I suggest you buy new connectors from Docent Electronics...we have bought dozens and dozens of them and they come with heat shrink for the ends. You can also buy new interconnect cables too. About one in ten of these interconnect cables have to be "fooled" with to make them work right...but thats easy to do.

There you have it all!! Todd

I would listen to Todd, he's been doing this for a long time and he know what he's doing.

One of these for power and one for ground and there would have never been any problems...

7691 (resized).jpg

You would thinks so, but..........

We have had screws loosen up on switching power supplies causing problems. Usually low voltage but when there are lots of power wires feeding other devices in the product, each with their own crimp eyelet, It can be a real bitch to track down when odd problems start to appear.

Nope... nothing beats screw terminals, nothing. Loose screws apparently can occur (I have never seen it in supplies such as our old 1980's 5V, 40A switchers that are still chugging along) compared to burnt or overstressed contacts. Loose screws are also not a design defect like undersized & insufficient connectors.
Pinball machines such as those old Gottliebs would have needed about 4 heavy ground wires and power wires. And these type terminals have been around since the 1960's so they can't say 'they weren't available back then.' Only reason they didn't --> money. If they would have put in this less than $1 worth of parts then nobody would be having these issues.
There is also no reason that new replacement boards can't be using these as well but some don't for the same reason... money. They save a whopping 20 cents each...

I agree. They would have prevented lots of failures. Not only in the pinball industry but the video game amusement industry as well. Just about every manufacturer I have encountered was guilty of undersized connectors.

About the only connector I don't think I have ever seen fail are Beau Connectors.

But as you said, the bean counters usually call the shots.

I'm sorry Todd but your approach is minimal at best. The whole reason for the ground mods is because the edge connectors just can't be trusted. Where other manufacturers had "hard" grounds (boards screwed to a metal back plane, which was ground), Gottlieb relied on connectors to do this.

The whole point of this is to make sure the grounds are SOLID. That is, they don't float (because of crappy connectors.)

Let me put it this way... If you drive a car into a ditch, is driving another car into the ditch making things better??? Because that's your version of the "ground fix", where you rely on the same crappy connectors (new or not) to do that job!

Another way to put this... Doing the same thing again and again and expecting different results, well, that's the definition of "insane."

And to add to that, you're using USED parts in the version of the ground mod you do? Seriously????

What i don't understand Todd, is why are you so lazy on this issue? it takes me about 15 minutes to do ALL the ground mods. ALL of them (including adding the interconnector wires you do.) This is one of those things where's you really can't do too much. Running hard (wires) grounds to the boards is the best way to handle this. Relying on the same crappy connectors (and used ones in your case!) that failed before is just, well, lazy and dumb.

Lots of opinions about ground mods so I dump mine too.

- doubling up the connection between CPU and driverboard is a good idea (with new pins)
- many of these groundmods are so poorly executed they are causing more problems then they are solving.
- using the 5V power supply heatsink as a ground plane is a big fail. You are connecting water and fire isolated by nearly nothing.
- performing the groundmod on 80B games with 0.093 connectors at the transformer assy is a wise thing. When there are 0.0156 KK connectors used with bifurcated crimpcontacts it is unnecessary.
- The filosophy behind the way Gottlieb was Star Grounding their boards is not bad at all. Ever heard a Gottlieb soundboard hum? Hello Williams and Data East owners!
- performing groundmods in system 3 games is bs.

I wouldn't characterize anything Todd does as "lazy" or "dumb". But you seem to have "insulting" and "disrespectful" on lock!

Dude, to say to someone like Todd with more than 30 years of experience, that what he does is lazy and dumb you need to have big cojones, if you know what I mean.

Please explain? I realize that one weak point in Gottlieb's design was at the gathered ground wires at the transformer assembly. And, I agree, the Star Grounding method is actually the correct approach for electronic design and preventing ground loops. Depending on generation, they used both inline 0.156 headers as well as 0.093 round molex plugs to attach the ground wires. Both suffer from the same fate: Cold solders to the headers on the PCB. But, as I would understand it, the 0.093" pins/connector carry more current and are less likely to move due to vibration. So why do you feel one requires modification while the other doesn't? ( I am only asking to learn.)

I know I am in the minority here but I would much rather service the connectors (cold solders) than perform the Solderless eyelet ground mod.

Instead of Bifurcated pins did you instead mean Trifuricon Pins?

736587 (resized).jpg

I like Todds videos, he's a great guy, approachable, and does know a ton about different fixes with experience- but on the grounding issue for Gottlieb, I'm going with Clay on this one.

It really does not take long to do the recommended grounds, and after you're done, it has a solid feel to it, because you know you did each one and they're in place, where as the lone ground wire in that connector is relying too much on a good thing to not go bad. It's pinball, things go bad.

No disrespect to Todd, because he's a good guy that knows his stuff, but I'll go to bat for Clay without even knowing him, on the experience level. Clays videos and guides have helped people too many times to count, myself included. Both of them have, really, they just disagree in some areas.

Agree, Todd is in the business of flipping pins. If it fixes it for the short haul & is a quick fix, that's all he cares about. Personally, I would rather take the time and do it right.

I am on your side. I prefer to service the connectors/pcb boards at the transformer assy. The 0.093" connectors are a PITA to refit with new contacts. The 0.156 are easy to redo so why do the hassle with an AMP lug? In our experience, the 0.093" contacts suffer more from aging despite the better specs and thus developing problems. The games with 0.0156 trifurcon ( indeed, i meant these, sorry about that ) contacts are rarely giving problems. For a good feeling, we just re-pin the connector which are carrying the grounds from the rectifiers to the transformer assy in case of 0.156" KK's at the transformer assy. I Always check if Trifurcon contacts are used. In some games, single action contacts are used, Arena often. In these cases, I always refresh all the connectors with trifurcon contacts.

For me this whole Ground Update story is a bit exagarated. Bad design by Gottlieb! Really? It is just like your car. It needs proper maintenance. And over the years some cracks, beeps, squeeks or whatever will arise. Servicing connectors after 25+ years doesn't sound strange to me.

How about no mods (a shocking confession).

27 years up and running ok without doing the typical board mods, on six System 80 games, in a mostly dry cellar. Cleaned up any PCB corrosion. Card edges got cleaned or retinned, a few pins and connectors were replaced, and some contact cleaner was applied. That's it, and some of these games came from damp storage. The games have been solid, except for cracked headers developing on the PSU's, and remote nicads, in plastic bags, wicking corrosive juices back up to the boards.

Did the John Robertson flippers.com version of the grounding mods this year, mostly for peace of mind. Figure those mods are a must for anyone that would operate or leave the games unattended. I've had thousands of boards through here, including quite a few burnt Gottlieb driver boards.

Opinions will differ. Let's agree to disagree, and keep it cordial.

From Todd's videos it hardly looks like he's doing quick fixes. He wants the games to last and keep happy and return customers.

Bifurcated contacts for slightly uneven surfaces such as 08-50-0116 for single sided and 08-03-0304 for double sided edge connectors. Of course, we all know the fate of the double sided contacts.

But going from solid to bifurcated for the single sided really doesn't buy you anything.

08030304 (resized).png

08-50-0116 (resized).jpg

The less time he spends fixing them, the more profit. Time is money in business. On the hobbyists side, we can take the time to do it right. I work cheap for myself.

And that is what Todd wrote, if you want to, you can do all the mods and take your time...

But he also say they did many many pins this way, during many many years and had no ground related problems again...

You choose, its your pin and your time