Igt S2000 sound problem - humming and static

[CaptainHappy]

DOCS FOR SPARE BOARD I HAD.

I posted these for people to have it it helps them and possibly me too!

CH

[CaptainHappy]

I believe it is caused by the back lit reel controller.

I even relocated back lit controller power connection from the Netplex harness for the top box (My connections where near the motherboard) to the actual power wires going to the motherboard.
I have done the MPU rework as posted in this topic for the 02 Rev A board.
I decided to try to see what may be causing the buzz in the speaker.
So I unplugged things that are not needed for basic machine operation: fluorescent lights, topper, back lit controller, printer, etc.
Added them back one by one until I heard the noise, took me a while waiting for machine to boot each time.
As soon as the machine was up with the back lit controller I heard the buzz.
I undid it and finished adding everything else back.
No Back lit controller no buzz, Back lit controller buzz is there.
The only thing I have not done is get another ferrite choke for the power harness going to the back lit controller.
I think back lit controller makes so much EFI/RFI that it travels right through the power into the audio section on the MPU and MMLB2

Foster,

I have to agree with you as I hinted toward the same thing of it being related to the backlit reels in my posts. Also the CN specifically states that the subject is: 80960 STEPPER BACKLIT REEL NOISE ON LEFT CHANNEL and in the text the cause is: THE LEFT CHANNEL DOES NOT HAVE THE CORRECT GROUND AND VOLTAGE ROUTING FOR THE 75510502 REV A AND 15510504 REV A BOARDS. The fix is a rework to correct and reroute the pwr and gnd. They go on to say that the 75510504 Rev B and 75510530 Rev C do not need the fix as the artwork was changed on them. My problem is that I think my board is a 75510504 REV E, can't read it fully right now. I would then assume logically that the artwork should have been corrected in this revision, but I had that EXACT problem as described.

My BIG problem now is that I do not get game sounds from the Left speaker anymore with or without the resistor mod.... Something died??? But as I stated in other posts, I can hear a VERY faint game sound in the left speaker... it is hiding in there.

Thanks for any thoughts!

CH

[idesign]

If you have a Multi Media Liite board in the machine it may be the problem.  If you do, try a different board if you have a spare.

[stayouttadabunker]

Excellent post ruden!

[Railroad94]

The 2 AMP boards   76924502 & 76928000  not sure if one was for I game or what, after checking  76924502 amp board and others have the 8000 board and hear no issues from the 2 different ones. all jumpers on the boards seem to be the same.

I thought Blueridge talked about the two different boards before but might of been on the old NLG.

[blueridgeslots]

The 2 AMP boards   76924502 & 76928000  not sure if one was for I game or what, after checking I realized I have one that is running the 76924502 amp board and others have the 8000 board and hear no issues from the 2 different ones. all jumpers on the boards seem to be the same.

I thought Blueridge talked about the two different boards before but might of been on the old NLG.

I don't know what I wrote before but here is some info I found notes on, the first is a list from IGT

13100300   AMPLIFIER ASSY-IN LINE,VSN RDY
13100301   REPLACED BY 13100302
13100302   REPLACED BY 13100303
13100303   AMPLIFIER ASSY-IN LINE,VSN RDY
13100304   REPLACED BY 13100400
13100400   AMPLIFIER ASSY,IN LINE, UNIV

my notes
13100400 is assy with 76928000 board and is in games I have seen made from 7/02 (both I+ and S-2)
13100301 is assy with 76924501 and is in I+ (4/2000)
13100302 is assy with 76924502 in S-2000 (11/00) but also have had in I+

New board number in 13100400 rev A is 76928001

[stayouttadabunker]

I'd try sticking a 400 amplifier assy in a 802 board?
Just to see if they're any sound problems?

[pinballmike49]

Just too add to the info  I have two machines with amp boards and back-lit reels. The one machine has a 504 Rev. B board and no issues with that at all. The other has a 502 Rev. A board and has loud hum  out of both speakers even after installing the 10 ohm resisters.

[Foster]

My amp assy is PN 13100401 Rev A,
Vendor 1001780 Date 646
Board 76928004 Rev A MC4306

[blueridgeslots]

My amp assy is PN 13100401 Rev A,
Vendor 1001780 Date 646
Board 76928004 Rev A MC4306

I should have went one more line down, but since it said AVP I didn't, but here it is for future look ups

13100401   AMPLIFIER ASSY,IN LINE, AVP1

[CaptainHappy]

I finally made a little more time to take a close look at this, and I have solved the problem!!! Thanks to all who contributed to trying to help me out! K+ To Be Distributed!  

As I had mentioned before I could not check my processor board model for sure (I thought that it was a 75510504 Rev E) due to the MMLII board being screwed down (Tight like it was done with air tools!   ) with STRIPPED screws. I also could not change the MMLII board as a test as well, and that was one of the first things I wanted to do!   I finally decided to drill the screw head (in the PIC you can see that I need a new hex standoff since the body of the screw is still inside! ) on the last screw that I could not get out. If you look at the first PIC you can see that the board is actually a 75510504 Rev EA, has anyone ever seen this REV before??? I do not think that it has the mod from the IGT ECN done in the artwork as the ECN suggests it should be done like the future revisions because it had the noise in the left speaker. I am old fashioned, but I thought that IGT would step their rev's in a normal manner like A, B, C, D, E, but who says IGT is logical!   I found another MPU board that I had put away was re-labelled as a rework 75510504 Rev B, and it had the rework done for IGT as described in the ECN.... If anyone wants me to I can take pictures of all of the rework on this modified board so that it can be documented here. Just holler if you want me to do that!

The problem that I found when I had the MMLII off the board and I could get it in good light for a good exam was that a capacitor was damaged on the MMLII board at location C59. SEE PICTURE!!! I am realizing now that I had never had the MPU board out of the machine before I noticed the problem, so I bet the left speaker was not giving game sound since I got the machine! When I picked it up recently I did not test it, and wish I would have now as I would have noticed this and some other things that I have had to fix!

THANKS AGAIN FOLKS!! More good reading for the folks that have a similar problem in the future. (Too many things went wrong at once... I also am thinking that I have a bad spare AMP too!) At least it is playing now.

Regards,

CH


NOTE: NO PICS FOR NOW, DUE TO THE FOLLOWING ERROR:

An Error Has Occurred!
The upload folder is full. Please try a smaller file and/or contact an administrator. 

I BETTER CONTACT AN ADMINISTRATOR!     OH, THAT WOULD BE ME!  

sTAY TUNED FOR picS LATER???

[CaptainHappy]

Hopefully attached are the two pictures mentioned above, that is if I ADMIN'd properly!!  

CH

[StatFreak]

NOTE: NO PICS FOR NOW, DUE TO THE FOLLOWING ERROR:

An Error Has Occurred!
The upload folder is full. Please try a smaller file and/or contact an administrator. 

I BETTER CONTACT AN ADMINISTRATOR!     OH, THAT WOULD BE ME! 

sTAY TUNED FOR picS LATER???

Hopefully attached are the two pictures mentioned above, that is if I ADMIN'd properly!! 

CH

So Mr. Admin, what did you tell yourself to do to fix the problem?   

Glad to hear y'all can hear your machine now, ya' hear?

[CaptainHappy]

It was a little strange in this case as I normally talk to myself all of the time, but I rarely listen, this time must have been an exception!!!!  I guess that I am practicing just in case I ever decide to get married! 

CH

[StatFreak]

I would think that if you wanted to practice for marriage, you'd continue ignoring yourself.   

SF

[stayouttadabunker]

Good time to brush up on your soldering skills capt and get yourself a new cap and solder it in!
The pictures are good...what are the major differences between the revisions?
The upgraded resistors, like ruden pointed out earlier?

[CaptainHappy]

Good time to brush up on your soldering skills capt and get yourself a new cap and solder it in!
The pictures are good...what are the major differences between the revisions?
The upgraded resistors, like ruden pointed out earlier?

That is going to be one of the projects that is put on the endless list! 

I think that you have the wrong board in mind for the damaged CAP... The part number picture is of the MPU board as I had never seen a REV EA before, and I was wondering if anyone knew about it? Also wondering since it seems to have the noise problem just like the REV A, and I assumed the problem was solved in REV B and beyond? SO why this one is not solved already is a mystery? I am not sure of the revision changes, so that is why I ask here, and I think you wonder the same? Who can set us straight on the revision history??

The second board pictured is not the MPU board, rather it is a MMLII board.

The upgraded resistors that I think you are referencing from Rudens post are his solution to the sound issue, and he was talking about putting them inline in the wires before the amp. That is unless you are talking about a previous post from a previous page? Right now I have the Mod of 10 ohm resistors put in after the amp before the speakers, and the sound is good. There is still a little buzz in the left speaker, but it is not near as bad as before, actually it is drowned out by the exhaust fan that is in the top box on the machine.

CH

[ichogger]

Confused noob. I have the hum on a Super Spin Sizzling Sevens. Do I need pots or resistors for my non-Vision game.

Thanks.

[stayouttadabunker]

Pots ARE resistors...except pots are "ADJUSTABLE" resistors.
I'd go with real resistors anyday...pots burn out and change values way too easily.

[ichogger]

Ok thanks. I bought 47 and 47k, plus some 100's and two other sets, 5 differents sets total. 99 cents for a pack of 5, surely I'll find something that sounds good.

Chuck

[stayouttadabunker]

Great! Hopefully you'll be humming away your humming noise...lol

Let us know how it sounds when you get the resistors in there!

[Bettor Slots]

Stout is right the pots won't work for you.  And take back the 47k packs...those won't work for you either.  The 47's are good but you might find the volume is too low even if it is set at max.  Best results seem to come from the 10 ohm resistors.   Also a tip, be sure to wrap all exposed wires and resistors with electrical tape or you will get some loud static noises when they touch the metal cabinet.

[ichogger]

I think I bought 10 ohms as well. They were only .99 a pack. I'm sure I'll find something to use them on.

What a great site, everyone has been very helpful so far.

Chuck

[CaptainHappy]

Just to add my 2 cents worth here...

I had good results with the 10 ohm resistors as well, and I used heat shrink tubing to seal it up nicely. (Just remember to slide the tubing over the wire before you solder "BOTH" sides of the wire to the resistor! )

CaptainHappy

[Foster]

I am using 47 ohm resisters or so pulled off dead S+ MPU's, without the amplifier in use.
What do I do if I want to use the amplifier?
Or is there a better MPU that quiets up the Hum and Buzz so the resistor are not needed?