Cap Your 90's Midway Sound Boards Immediately

Watching this with interest. I have too much pulled apart at the moment to take more apart, but I'll likely pull my sound board next week and recap it.
 
Thank you @gutz and @Marquee Mark for the advice. I ended up swapping all 7 of the electrolytic radial caps tonight after looking up the series codes even on the "newer" old caps and seeing they were from Nichicon's "standard" line, not the "High Reliability" line that @security0001 includes in his kits.

I used the method that @zenomorp demonstrates in his video here:


Everything went well. There was one cap that the pad was definitely already missing when I pulled the old cap. Luckily the trace was easily accessible so I exposed it with a fiberglass pen, and then folded the cap leg over to run along the trace and soldered it down solidly. All the others went fine using that #1 desoldering braid.

Reinstalled the board and my sound was great! I still have a couple T2 sound boards to do yet but at least this first one went well!
 
Need some advice or a cross-check on the board for my SmashTV 19". I sat down to do several soldering projects today, including the cap kit from APAR for this game, but some parts aren't matching up and I need to figure out if my game has incorrect parts installed or if the manual is incorrect. Worth noting that although I don't know the full history of the board, my game is a 19" SmashTV which was one of the early runs before the switched to the larger 25" cabinet.

Sound board has 5766-13702-00 screened on it, and the manual calls it D-11581-3044.

I asked @security0001 and he said his kit for the D-11581 series should work. My board has tantalum caps instead of electrolytic for the axials but Peter said I could skip those, so no problem there.

View attachment 803533

There are 7 radial electrolytic caps:

C12, C19, C24, all rated as 100uF 35V per the manual, and

C26, C30 (470 uF 16V)
C29, C32 (1000 uF, 16V)

For C26,29,30,32 the board has 85* Nichicon VR(M)s installed in the correct values with 2022 date codes.

View attachment 803534
View attachment 803535

Guessing someone did these a few years ago before I bought the game although not with the same caps Peter provides.

But C12,19,24 all presently are populated with 150uF 35V caps, whereas the manual and the cap kit specify 100uF 35V. These are Nichicon 105* PF(M) caps with 1999 date codes, so clearly replaced at some point after the game was manufactured:

View attachment 803536

So two questions:

1. Worth replacing 2022 85* caps with same rating 105* 2023 caps for those 4?

2. Should I replace the 1999 150uF caps with new 100uF caps, which match the manual? Or might there have been a reason 150's were installed?

I am *guessing* these may all have been replaced at the same time as all 7 of the caps are cut VERY flush on the underside, no "nub" of the lead poking out of the solder as all the factory parts have. But if that's true, whoever did it installed 20 year old caps with what looks to be the wrong rating for 3 of the locations.

The game/sound work 100% fine on this game right now, so I'm not looking to unnecessarily tickle the dragon here, I was just trying to be proactive per @zenomorp's advice in this thread!

Thanks for any thoughts or advice here!

I just got Spy Hunter back together and pulled the SMASH TV sound card and it's a bit different than the one that you posted.

Mine is labelled as D-11581-3044 and has 5766-12130-00 rev d screened on it.

PXL_20250314_041420509.NIGHT.jpg


And my C1, C3, C4, C8, C11, and C17 appear to be electrolytic?

PXL_20250314_043203019.jpg


So @security0001, this is the right link? And I also need to replace C1, C3, C4, etc?

 
I just got Spy Hunter back together and pulled the SMASH TV sound card and it's a bit different than the one that you posted.

Mine is labelled as D-11581-3044 and has 5766-12130-00 rev d screened on it.

View attachment 806189


And my C1, C3, C4, C8, C11, and C17 appear to be electrolytic?

View attachment 806190


So @security0001, this is the right link? And I also need to replace C1, C3, C4, etc?


Description
Williams D-11581-574 / D-11581-40003 / D-11581-3044 Audio Sound PCB 105C Cap Kit. This Williams sound board cap kit works on pinball games such as Whirlwind, SMASH T.V. and any other williams D11581 (William System 11B) pinball games with this sound PCB and this kit will also work on Arcade games like Trog with the D-11583-40003 (16-8850-348) sound PCB. "Mega Deluxe Cap Kit" All capacitors are 105c including the Axial caps in this kit. All of our Cap Kits / Get Well Kits include a sticker so you can place it on the PCB to help you keep track of the work you did and when it was done. 13 Capacitors total included in kit with great instructions. Our kits have some of the BEST quality, low ESR, and longest life capacitors in them.


yes
 
I have never recapped one of these Midway sound boards before. I just finished up an MK2, and the very first pad I thought I lifted. I did it exactly like Mike's video, but it appeared to pull the pad off the face of the board. Upon testing with a multimeter though, everything was perfect. It took solder too, so what looked like a pad was just a piece of solder from the leg of the axial cap. I almost lost my mind off the start, but stuck through, and got the board back up. No issues, and thankfully no trace damage from leaks!
 
I have never recapped one of these Midway sound boards before. I just finished up an MK2, and the very first pad I thought I lifted. I did it exactly like Mike's video, but it appeared to pull the pad off the face of the board. Upon testing with a multimeter though, everything was perfect. It took solder too, so what looked like a pad was just a piece of solder from the leg of the axial cap. I almost lost my mind off the start, but stuck through, and got the board back up. No issues, and thankfully no trace damage from leaks!
If you want to simply work on soldering skills, get a working electrical item from a thrift store and have at it. That way if you mess up, no big deal
 
If you want to simply work on soldering skills, get a working electrical item from a thrift store and have at it. That way if you mess up, no big deal
No no, I have ample soldering experience, but as Mike mentioned in the video, these pads are extremely delicate. I thought I lifted the pad, but it was not the case. With the Hakko at 400c, some good wick, and some patience, the board turned out flawless (pun intended).
 
No no, I have ample soldering experience, but as Mike mentioned in the video, these pads are extremely delicate. I thought I lifted the pad, but it was not the case. With the Hakko at 400c, some good wick, and some patience, the board turned out flawless (pun intended).
Got it. Perhaps somebody with limited experience will read my comment some day and take the advice.
 
Thank you @gutz and @Marquee Mark for the advice. I ended up swapping all 7 of the electrolytic radial caps tonight after looking up the series codes even on the "newer" old caps and seeing they were from Nichicon's "standard" line, not the "High Reliability" line that @security0001 includes in his kits.

I used the method that @zenomorp demonstrates in his video here:


Everything went well. There was one cap that the pad was definitely already missing when I pulled the old cap. Luckily the trace was easily accessible so I exposed it with a fiberglass pen, and then folded the cap leg over to run along the trace and soldered it down solidly. All the others went fine using that #1 desoldering braid.

Reinstalled the board and my sound was great! I still have a couple T2 sound boards to do yet but at least this first one went well!
That's a great video @zenomorp

Thanks for bringing this to our attention. I'm getting started on this.
 
Working on a pile of the "other" type of model 2 sound amp with the RCA inputs, as found in VF1/2, VC1, FV, etc.

Every single one of these boards has leaking Marcon-brand caps. A few of them caught some damage to the traces since these are single-sided boards.

If you have any Sega Model 2 game, the sound amp needs caps.

segaamps1.jpg

segaamps3.jpg


segaamps4.jpg
 
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Do the axial caps on these tend to leak? I've only done three of these soundboards and found that only the radials (as mentioned) are leaking.

Also, I noticed that in the APAR kit, one of the axials is of a different value than what was actually on my boards. I don't remember what position it was but the board had a 10uF 25V cap there but the kit provided a 47uF cap for that spot. What's the reason for that (not mentioned in the docs provided with the kit) @security0001 ?
 
Do the axial caps on these tend to leak? I've only done three of these soundboards and found that only the radials (as mentioned) are leaking.

Also, I noticed that in the APAR kit, one of the axials is of a different value than what was actually on my boards. I don't remember what position it was but the board had a 10uF 25V cap there but the kit provided a 47uF cap for that spot. What's the reason for that (not mentioned in the docs provided with the kit) @security0001 ?
I've never seen one of the axial capacitors leak, but it's also rare to find them still within spec for tolerance on capacitance/esr. I would estimate less than 20% of the axials have been good in my experience. Watch the videos in post #5.
 
Do the axial caps on these tend to leak? I've only done three of these soundboards and found that only the radials (as mentioned) are leaking.

Also, I noticed that in the APAR kit, one of the axials is of a different value than what was actually on my boards. I don't remember what position it was but the board had a 10uF 25V cap there but the kit provided a 47uF cap for that spot. What's the reason for that (not mentioned in the docs provided with the kit) @security0001 ?
there are many variations so either someone replaced it with that or it was upgraded later on as i have made the kit per the boards and manuals so i would stick to the kit.
 
Do the axial caps on these tend to leak? I've only done three of these soundboards and found that only the radials (as mentioned) are leaking.

Also, I noticed that in the APAR kit, one of the axials is of a different value than what was actually on my boards. I don't remember what position it was but the board had a 10uF 25V cap there but the kit provided a 47uF cap for that spot. What's the reason for that (not mentioned in the docs provided with the kit) @security0001 ?
I had an NBA Jam board where the blue Philips caps leaked (I'd even created a thread about it) ... the caps outgassed in the area of the sound board header, so it wasn't able to get any of the calls out to the sound board until I replaced all the resistors and cleaned it up. I had bought replacements for those caps years ago, I don't know where they are now.

it's a known problem with Williams WPC hardware, which is of the same era: https://pinwiki.com/wiki/index.php/Williams_WPC#Failed_Electrolytic_Capacitor_on_the_MPU

I second just replacing the caps within the spec of how APAR made the kits. you never know what's been modificated over the course of time with any of this stuff.
 
I have never recapped one of these Midway sound boards before. I just finished up an MK2, and the very first pad I thought I lifted. I did it exactly like Mike's video, but it appeared to pull the pad off the face of the board. Upon testing with a multimeter though, everything was perfect. It took solder too, so what looked like a pad was just a piece of solder from the leg of the axial cap. I almost lost my mind off the start, but stuck through, and got the board back up. No issues, and thankfully no trace damage from leaks!
Lol yes this happens a lot with those I think its because the solder is so old even a little heat and it tends to lift right off before melting all the way kinda looking like you lifted and broke the trace but didnt.

To add to Mikes video, which I basically do the same way, but I use one of these tools with kind of the space for the lead in the middle and then you can use it as a wedge for the other lead of the cap still soldered in instead of trying to pull on it. Everyone should have some of these they have a bazillion uses soldering, again you dont want to put too much pressure it should lift right out no problem or you are not getting the solder melted.

https://a.co/d/d26wmb9
 
MK1, MK2, NBA Jam, Smash TV, Total Carnage, Revolution X, Judge Dredd (unreleased but still counts), Terminator 2, High/Super Impact, and a couple others I can't think of right now. Any game that uses a separate sound board.
Aw man (T2 owner)

Can someone pls confirm which kit I need? Is it definitely the same as MK1?
 
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