IIRC it's either 18 awg or 16 awg that's already on there.

-Hans

Any auto parts store sells small rolls of wire that are the right gauge.

I bought a Lucky Seven today, looks like it could use some of the tips posted here along with a few other updates.

http://imgur.com/ui7PtQx,i3jslY4,EuNUzh1,YN5roPr,rJMxNSa,1UP86xq,RM1giNq,0PMAuCA,PWsvP53,pE5bxPx,VPAsKrF#2

It's full of a lot of "Um's", but I just uploaded a video today of using the diagnostic testing built-into a System 4-6 machine.

I'll be doing one for System 7 in the near future, there's a few differences in there. No access to a System 3 unfortunately, as that's dramatically different in how it does settings, but I'll figure something out to do a video on that.

-Hans

You haven't mentioned the sound board, is it worth replacing components on the sound boards as well? Or are they not as susceptible to failure?

Most of the sound board issues I've come across tend to be caused by the ribbon cable failing. It's kinked so badly that the internal conductors fail. But it is fairly easily to replace without soldering, and cheap too.

http://www.siegecraft.us/the_siege_blog/blog/2012/06/speech-board-ribbon-cables.html

Since you are dealing with audio, I do like to replace the caps on my speech boards, if nothing else it does clean up the sound quality a bit. Also make sure to use all the mounting screw holes when you install them, and make sure the screws are tight. A weak chassis ground can cause static and distorted sounds.

-Hans

Nice write up on the speech board ribbon cable Hans. I have at least one dead speech board because of that stupid cable, didnt think you could pry it up and replace it that easily. I will have to go try this soon.

The Real Bob Roberts sells the cable, too. I believe it has solder tails on one end, and an IDE cable end on the other.. but that be 40 pins to desolder and resolder.

I have seen some Type 1 soundboards using a 12000mfd filter cap, while some others and the Type 2 boards all use a 4700mfd cap. If you're replacing caps and have the 12000mfd on yours, you can save a few bucks with the 4700mfd replacement.

Yeah, sometimes you just don't have a choice if the solder side connector breaks. But if you take your time and go easy, it separates without a problem most of the time.

-Hans

Now that I have my Firepower running, at first the displays are normal, but after they are on for ten minutes they go dim, except for a couple of segments so you see random numbers, one in each player's display. Does this sound like something that will improve when I get to this section of the Bulletproofing?

I'll check tomorrow, I haven't measured.

I didn't get a chance to measure voltage yesterday, I'll try today. But I'm also going to try to do the whole power supply step tonight. I have weak flippers, sling shot, and kickback and the contacts look like they have proper 1/8" gap. I have new flipper parts ordered anyway so I didn't check voltage there yet either.

What is the best way to measure voltage at the bridge rectifier? I put my black lead on ground and my red lead on the top fork and read 13.7VDC. The lamp rectifier I read 7VDC. I'm assuming I'm doing this wrong. As for ground, just using the cabinet.
Thanks.

I replaced the caps on the lower supply and reflowed the solder on the header pins today. I didn't get to replacing diodes and resistors yet. I was adjusting the contacts again on my flippers and when I tested them the machine died and the MPU board had solid LEDs. After turning it on and off a couple of times, the game came on normally. Then after it sat in attract mode for about five minutes, the MPU shut off again. Now it's been in attract mode for twenty minutes after I've played a couple of games.

After all that description, my question is does it take a bit for the capacitors to get to their capacity? Could that have been the issue? Or is there something else going on. I still plan to do the rest of the steps, but I wanted to do a little at a time so if I made a mistake I wasn't backtracking a lot. I also want to order new connectors all around.

Vid,

Everyone always says you can't put a sys3-6 driver board on a system 7 CPU, but why?

They appear to be exactly the same board.

One difference, look in the upper right corner while holding the 40 pin connector up... You'll see that instead of resistors on the switch matrix, they used 0 ohm jumpers on the system 7 board. This is one change to make the switch matrix more responsive.

You'll want to match a 7 with a 7, but I don't think you HAVE to. If you don't then you could get intermittent weirdness in the switches.

I never got them.

Thanks for the guide, it makes perfect sense now!

R196-R203 are resistors on some Sys7 driver boards, and are zero ohm jumpers on some. I've seen them both ways, and never understood why.

Big Daddy Enterprises has the correct zero ohm jumpers. They are cheap, so I use them for a 'factory' look.

I use the zero ohm jumpers so often, I buy them in spools of 1,000 from Mouser. Same with 1N4004's.

Over time, the resistance value of those things dropped a couple times, but I do question if it's a generational thing or just an evolution of the design. After all, the CPU doesn't even read those resistors.... the PIA chip does and they go through additional logic chips first. And the CPU speed never changed either, 6800, 6802, 6808.... all run at 1mhz. Started with 1k for System 3-4 and into early System 6, mid-way through system 6 they dropped to 330 ohms, and at System 7 dropped to zero ohms. The signal direct signal from the switches never even reaches the CPU board.

-Hans

Very possible. I remember reading somewhere that there were changes to how System 7 reads switch hits, due to limitations in the earlier designs when it came to multiple closures in a row (or was it column) at the same time. Unfortunately I've never found that reference again, so I can't provide any details.

-Hans

Hey Vid, thanks for the awesome guide! I am ordering parts to perform all these updates on my machine.

One quick question, you suggested removing the 27 ohm resistors and replacing them with jumper wire when replacing the TIP42 parts with MOSFETs. If I replace the 2N6122 parts on the row drive (Q47, Q49, Q51, Q53, Q55, Q57, Q59, Q61) circuit with MOSFETs (IRFZ34NPBF), can I replace the .4 ohm 3W resistor with a jumper? What about the 100 ohm 3W?

I added the fuses to my Sorcerer last night. Thanks Vid!

Looks like a lot of these fixes can also apply to Sys 9 as well. Time to get a spreadsheet going on all the components needed for the whole 'bulletproofing' process.

Hey Vid,
Im having some issues with GI in a system 6 Scorpion. I read somwhere that Williams did a service bulletin regarding GI in these system of titles.... I think splitting the GI into 4 sections with 4 5A SB fuses, rather than the one 20A fuse.. you have any idea on this, seems it would save me some time tracking down the issue and help others in the meantime.. the trick I see is that there is a relay that turns the GI on and off for gameplay, so hoping you can shed some light..

What problem are you having?

Just blowing the 20a fuse, since all of the GI is tied together its making finding the issue a real bitch. I suspect a socket or two is giving me problems but I cant track down the short, as I could have issues on multiple lines... I could hook up each run one at a time which I have done but got mixed results, that service bulletin would be handy but its a "binder" item in the old repair manual and its not scanned out there anywhere...

After the last several project games I've worked on, I'm with John on this. Too much thinking everything is all fixed and good to go only to have to keep pulling boards back out after a week or a month because one of the score displays started acting up or the sound started playing the wrong sounds... Just get a big sack of 9 pin headers from Tayda, at $.10 each it is so worth it.

Hmm, well, I'm not sure how that's going to work if it all has to go through the one relay.

For GI issues I usually start by taking all the bulbs out and clipping an old 9-volt onto the GI wires, then adding bulbs one at a time. But that's with the playfield out of the machine and disassembled, so probably not much help in this case...

The relay only came into play for System 7, and Blackout in System 6. Otherwise, there's no relay to worry about in the vast majority of system 3-6 games.

I have a fuse block, and this is a scorpion, which does have a GI relay, I started on this last night, but the relay has me guessing, ill post a pic a little later

Here is a pic of what Im looking at, my guess is to fuse the 4 yellow wires as they were individually, with the white stil tied together on the relay..
d10caf8f-27af-4e66-ac3a-360b6a618c84_zps7234be18.jpg

Thanks Vid1900!