S+ Reel Misstep issue

[poppo]

U2, U10 & U11 are most likey to cause reel problems as they are the stepper drivers. U1 and U5 are for reels 4 & 5 and can often be used as a spares if you only have 3 reels.

[stayouttadabunker]

U2, U10 & U11 are most likey to cause reel problems as they are the stepper drivers. U1 and U5 are for reels 4 & 5 and can often be used as a spares if you only have 3 reels.

Yes, I forgot to mention those ones.
I've changed out a few of those as well.
Various board revisions have them marked at different locations and to make matters worse -
some have unoccupied sockets!
Most REV. MPU's have just a socket at the U3 location with no "butterfly" chip in it.
I assume the "butterfly" wings on those chips was to act as sort of a heat disperse / heat sink.
Because of all the different revisions of MPU's - it is nearly impossible to track what is what anymore.
There's no way I could obtain that many different schematics to try and decipher what was going on.

So every time I tried to repair a "reel tilt" board, it was trial and error of swapping IC components to see what was causing the tilts.

[poppo]

I assume the "butterfly" wings on those chips was to act as sort of a heat disperse / heat sink.

Yep.

Because of all the different revisions of MPU's - it is nearly impossible to track what is what anymore.

That's only because you keep getting all of those 'made in Mexico' boards.  

[sblair]

I suspect that the R1-R5 bank was primarily used for "holding" the reels at "attention" during non-play/idle mode.

Where do you get that from?  Looking at the schematics, it just looks like R1-R5 are biasing resistors for LED's on the Reels.

[poppo]

Where do you get that from?  Looking at the schematics, it just looks like R1-R5 are biasing resistors for LED's on the Reels.

No disrespect intended, but some of us have been messing around with these machines for years. Many times we find things that cause problems that don't seem to make any sense. And the resistors are for the reel optics. If they are not working, the machine won't detect the reels moving and hence won't know where to stop them.

[sblair]

No offense taken, that's why I was asking the question and why I'm here to begin with.  From my schematics I couldn't tell those were for the optical sensors by how they were labeled.  The schematics I have are a very poor scan quality and quite hard to follow as a result.

[poppo]

The schematics I have are a very poor scan quality and quite hard to follow as a result.

Also as already noted, there are different revisions (plus there are known errors on some of the schematics), so a lot of what people post as possible solutions is from trial and error etc.    In actuallity, we rarely mess with the MPU schematics. Once we go over the basic steps (i.e. what SS & SP chip, check the pins, check the cables) a MPU swap is in store. Since they are so cheap, most people don't even bother trying to fix them unless it's something common like a bad battery or one of the stepper drivers (since there are spares on the board).

 

[stayouttadabunker]

Yes...I've used the R4 and R5 as spares to repair any one of the R1,R2 or R3 resistors.
You'll notice that those particular three resistors go out of whack and actually burn into the board!

Take a board and hold it up with a bright light behind it.
(Old way of casino backroom troubleshooting... )
You will definitely see which IC components throw out a lot of heat!
It will be brownish color on the circuit board around the suspect component.

I have found that sometimes changing them out with the unused spares, makes the reels "hold" during idle whereas before,
they would throw out reel tilts and start slowly turning.

Poppo's right about trial & error, swapping and changing out stuff.
That was all we were capable of doing...nobody went to tech school for this stuff!
We didn't have money to go to school!
Heck! Some of us never finished high school! 
I was lucky enough to go to Cornell University but I never took up electronics
but could fix a pinball machine or repair an 8-track player!
Figure that out?!?!

[sblair]

Also as already noted, there are different revisions (plus there are known errors on some of the schematics), so a lot of what people post as possible solutions is from trial and error etc.     In actuallity, we rarely mess with the MPU schematics. Once we go over the basic steps (i.e. what SS & SP chip, check the pins, check the cables) a MPU swap is in store. Since they are so cheap, most people don't even bother trying to fix them unless it's something common like a bad battery or one of the stepper drivers (since there are spares on the board).

 

What does a replacement S+ MPU board run out of curiosity?   I'm going to first try replacing U23 on mine when I get back in town and see if that solves it, if not depending on price I might just replace it.

[poppo]

What does a replacement S+ MPU board run out of curiosity?   I'm going to first try replacing U23 on mine when I get back in town and see if that solves it, if not depending on price I might just replace it.

I've seen them as low as $15 + shipping. There are some overpriced ones on e-bay right now, so it's best to just put a WTB in the classifieds here. Also be sure that you get the right one. There is a 10Mhz and a 16Mhz version. You have the 10Mhz. You would need at least a different game chip if you got a 16Mhz one. The reel chip would have be 120ns or faster. The main difference is the 16Mhz board has no dip switches and no volume control knob. The volume is set in the self test mode. Of course the board is a little faster, but it can also cause a buzz in the speaker. I prefer the 10Mhz.

[stayouttadabunker]

If you're out west, Try slots4home for an S+ board.
He has good prices.
If not, the a WTB ad in the "Classifieds" section of NLG would help! 

On the east coast there's a lotta guys that might help you out.
Blueridgeslots, Raz10, Rudy's Deals are good sellers!
Of course there's Samron slots, Ohio gaming and a whole bunch in Ohio too!
I'm not sure who has them in the Midwest though...Brian of rockymountainslots maybe?
Is the state of Ohio midwest?    lololo
There's a whole bunch of good vendors up on top of the homepage here!

[sblair]

Just to follow up here.  I decided to go the route of replacing the board.  Not because I wanted to but because that is the cheapest option.  The UCN5810A in U23 is one of the chips that got caught up in the Allegro mess when they exited the driver business and there are no suitable cross's to substitute and the one place I found that I could buy one from had them priced more than getting an entire new MPU board (with a fresh battery) would cost.

I'm a bit bummed because I really wanted to fix the other PCB as I am pretty certain it is just U23 that needs replacing....oh well

[stayouttadabunker]

blair,
If you PM me an address - I will remove a chip from one of my old ones
and send to you to see if that will work or not?