What's new
By:
Pinball info

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Stern node fault

My $0.02 (and no - I am NOT bashing Stern or anyone, just tipping my thoughts into the discussion).

The MP24943 is a switching regulator that is specified to deliver 3A output with a MAXIMUM recommended input voltage of 55V.

AFAIK, this node board derives its supply from the 48V switching power supply which is then fed to the input pin of this chip as well as many other places.

Pin 1 of this chip is the voltage input pin - this seems to be where the blammo (technical term) happens on a few of these I have seen.

My electronics experience tells me do not EVER rely on a small margin of safety when designing things. This device is being supplied with an input voltage that is only a small margin above its suggested MAXIMUM operating condition. 48 VS 55 is FAR too close for my liking and I would NEVER, EVER design such a thing.

In practice, my thoughts are proving correct. This device is simply running way too close to its maximum operating conditions and we are going to see many, many more failures just like this.

Fortunately, this device is cheap and common and replacing it should be a fairly easy task for a competent technician. Forget field repairs but a bench repair on this problem should be easy to effect and simple enough to test once done.

I think this is a classic case of a "fresh from uni" engineer with little, to no, real world experience designing this product. They are usually great on theory and dumbfounded when things like this happen to their designs. Clarifying again that this is just my opinion - and after all, what would I know?
 
Stern have had the node board listed on there site for $99 for over a year but it’s never been in stock
Sadly with the limited supply of parts it looks like all node boards are been allocated to the production line I don’t know any distributors who have any in stock apart from pinball life at silly money
 
That node stabilisation kit has been fitted wrong and has pulled/twisted that transistor! The spacer should go the other side in the gap created where the two transistors are offset from each other, not one bit surprised it’s failed - I bet, as people have suggested, that it’s D9 that has broken!
 
From the ones i've seen its not voltage regulators that seem to be the problem. Cabinet node ones i've seen regulators go and normally then you get a big hole in your board/ burn up of it. The node 8/9 issues seem to be data related and we just don't have enough info on how these bloody things work to fix them. We are at the point now where we really need an OEM diagnostic tool like with all cars from the last 20 years that can read the internal cpu and output what its whinging on about. Saying 'Node 8/9 not found' isnt much use and stern knows this!!!

Previouosly i thought the above was a moot point as stern had lowered the price to mitigate repairers like me bothering to try and repair them, but now we are in a different world with limited supply of electronics for the foreseeable so who knows what the best option is going to be.

If you buy a new stern then good luck :) and if it worked for 2 years then well done! remember sterns warranty is 90 days and that starts from the day its put in the container :)
 
Last edited:
Homepin said:
I think this is a classic case of a "fresh from uni" engineer with little, to no, real world experience designing this product. They are usually great on theory and dumbfounded when things like this happen to their designs. Clarifying again that this is just my opinion - and after all, what would I know?
Click to expand...

I suspect its some over confident old git with no self awareness that designed it; and after all, what would I know?!
 
I am happy to look at the board to see if there's anything i can do to get it working again, but i'd need to see it to see. there are some 'things' we can check and try before resigning it to the bin
If repairable you'd be looking at £125 plus vat. If not then it would be £50 plus vat test fee. All plus shipping
 
CHRIS B PINBALLS said:
Stern have had the node board listed on there site for $99 for over a year but it’s never been in stock
Sadly with the limited supply of parts it looks like all node boards are been allocated to the production line I don’t know any distributors who have any in stock apart from pinball life at silly money
Click to expand...
it was in stock but someone cleaned them out 😎 CPU's too! :D if you snooze you lose :D

I suspect they are regretting selling them so cheap given the supply chain shortage
 
myPinballs said:
From the ones i've seen its not voltage regulators that seem to be the problem. Cabinet node ones i've seen regulators go and normally then you get a big hole in your board/ burn up of it. The node 8/9 issues seem to be data related and we just don't have enough info on how these bloody things work to fix them. We are at the point now where we really need an OEM diagnostic tool like with all cars from the last 20 years that can read the internal cpu and output what its whinging on about. Saying 'Node 8/9 not found' isnt much use and stern knows this!!!

Previouosly i thought the above was a moot point as stern had lowered the price to mitigate repairers like me bothering to try and repair them, but now we are in a different world with limited supply of electronics for the foreseeable so who knows what the best option is going to be.

If you buy a new stern then good luck :) and if it worked for 2 years then well done! remember sterns warranty is 90 days and that starts from the day its put in the container :)
Click to expand...

If you had a spare central cpu node board you could in drop it in for testing as per: https://docs.missionpinball.org/en/latest/hardware/spike/connection.html

The list of commands there has: node: node diagnostics commands. Not sure how detailed that command actually is.
 
  • Like
Reactions: Arv
Neil McRae said:
I suspect its some over confident old git with no self awareness that designed it; and after all, what would I know?!
Click to expand...
Typical response I expected from you. I certainly have enough technical training as well as many years of practical work to back up my comments. Anything I design doesn't explode like these regulators do (and they do it often enough to be an issue) and it is purely and simply "poor design" no more, no less.

How about offering a soloution to the problem rather than mouthing off. You simply cannot defend Stern for this cockup - this part should NEVER have been used in this position IMO.
 
Thanks and I have to agree it is the engineering. I do not have the technical background you do, but a home use machine with under 400 plays should not just go to ****. I saw the one on pinball life for $440, but that is just stupid price gouging. The manufacturer really has to step up and get behind this product or I just have a very expensive paper weight. I have a Mandalorian on order and it seems the smart bet would be to cancel that order until they can get their act together. I'm just one person, but I cannot be the only one who is getting stuck like this.
 
I have a iron maiden le, which I set up in the last couple of weeks and after about 10 plays came up with the node 9 message, after investigating has 29 life time plays 😳 . Contacting stern to see what can be done and will definitely be reflecting my experience
 

Attachments

  • C502C069-CBEE-424E-B070-FEBD58E56A01.jpeg
    C502C069-CBEE-424E-B070-FEBD58E56A01.jpeg
    147.4 KB · Views: 35
Homepin said:
Typical response I expected from you. I certainly have enough technical training as well as many years of practical work to back up my comments. Anything I design doesn't explode like these regulators do (and they do it often enough to be an issue) and it is purely and simply "poor design" no more, no less.

How about offering a soloution to the problem rather than mouthing off. You simply cannot defend Stern for this cockup - this part should NEVER have been used in this position IMO.
Click to expand...

Mike,
Love it! Its ok for you to have a go at someone but not ok when that someone is you? If you are going to dish your drivel out mate, be prepared to take it. I'll make a deal with you, you don't spout your nonsense and I won't hold you to account for it?

you also seem to mis-understand. I'm not in the business of making pinball machines. I'm in the business of +buying+ them.

And I can easily defend Stern - they make more games than all the other manufacturers in the industry put together- and have a handful of board problems. I'd guess they have a MTBF not significantly worse than most electronics today and not significantly worse than the industry as a whole.

I've had one board failure from Stern, Spike 2 CPU (which is a well known CM'ed design used in thousands of applications and NOT designed by Stern). So since 2016 with over 25 games a single failure, and not a single node board failure. 5 of those games get an absolute hammering and they run and run and run. Most folks I talk to about putting games on location only want to put Stern games on site because they are reliable. But for the record, the last electronics design I did the line cards cost hundreds of thousands of dollars and getting it right was pretty important.

Regards,
Neil.
 
mission65 said:
I have a iron maiden le, which I set up in the last couple of weeks and after about 10 plays came up with the node 9 message, after investigating has 29 life time plays 😳 . Contacting stern to see what can be done and will definitely be reflecting my experience
Click to expand...
Have you checked & reseated the Ethernet cables - the one on the left in your photo looks like it being pulled tight.
 
"If you are going to dish your drivel out mate, be prepared to take it. I'll make a deal with you, you don't spout your nonsense and I won't hold you to account for it?"

I am offering my technical opinion on the problem discussed in this thread. It is your opinion that I am talking nonsense and spouting drivel and your comments are a direct slander towards me and my technical expertise.

I am not putting Stern down rather pointing out that someone at Stern, or a contracted company, has made a poor choice in this case and I have made it very clear (4 times now) that it is my opinion based on my experience and NOT a dig at Stern.

I am NOT bashing Stern, far from it, they do many things right there is no doubt. This issue however is one that should never have happened.

I am still to see anything from you that might help - I have suggested it should be reasonably easy to repair - all you can say is "stuff everyone else, I haven't had a problem". Fair enough, that shows anyone reading just what sort of person you are with zero empathy for those who genuinely do have a problem and want to know how to fix it.

You can go and put on your 'Stern Army' shirt now and be all smug knowing you don't have any issues with this design flaw and TOUGH for anyone who does.
 
Homepin said:
I am offering my technical opinion on the problem discussed in this thread. It is your opinion that I am talking nonsense and spouting drivel and your comments are a direct slander towards me and my technical expertise.
Click to expand...

LOL are you kidding me?. Go read what I took issue with, nothing to do with your "technical capability", but I look forward to your LBA :rofl:
You made a ridiculous comment about the age of the person that designed the board, I offered my opinion on that and you didn't like it because it was clearly too close to home! Boo freaking hoo.

Homepin said:
I am not putting Stern down rather pointing out that someone at Stern, or a contracted company, has made a poor choice in this case and I have made it very clear (4 times now) that it is my opinion based on my experience and NOT a dig at Stern.
Click to expand...

Sure, so why mention what you thought the age of the designer was? What has that got to do with the price of fish?

Homepin said:
I am NOT bashing Stern, far from it, they do many things right there is no doubt. This issue however is one that should never have happened.

I am still to see anything from you that might help - I have suggested it should be reasonably easy to repair - all you can say is "stuff everyone else, I haven't had a problem". Fair enough, that shows anyone reading just what sort of person you are with zero empathy for those who genuinely do have a problem and want to know how to fix it.

You can go and put on your 'Stern Army' shirt now and be all smug knowing you don't have any issues with this design flaw and TOUGH for anyone who does.
Click to expand...

Sorry but you still confuse me with someone who makes pinball machines. I'm not. I'm one of those things that the pinball industry does a **** poor shocking job of looking after.

I am the customer! I'm the person that orders the games, pays for the games and plays the games. I'm not the manufacturer, I'm not the designer, I'm not even the salesman. I'm the customer.

I've contacted folks at Stern to help with folks other issues as I know some of the people at Stern, sometimes it has helped sometimes it hasn't; are people posting problems making them up? Of course they aren't and its frustrating when you get early life failures like this but the reality is they happen (I remember an early life issues on a certain ramp!), the games have warranties and you can claim via them or if you buy it second hand then thats a risk you take knowing the price of the boards and their "unrepairability" but it seems most folks are ok with that because they sell tons of new games, the second hand market is buoyant but pinball is an expensive hobby.

Regards
Neil.
 
Andydn said:
Have you checked & reseated the Ethernet cables - the one on the left in your photo looks like it being pulled tight.
Click to expand...

hi Andy, thx for advice, but yes reset Ethernet cables and even swapped them out, but no joy
 
mission65 said:
I have a iron maiden le, which I set up in the last couple of weeks and after about 10 plays came up with the node 9 message, after investigating has 29 life time plays 😳 . Contacting stern to see what can be done and will definitely be reflecting my experience
Click to expand...

not 100% sure but I thought the lifetime counter came in some time after IMDN had come out? Have you the history of the game are you sure abut the number of plays? In any case its a ****ter for sure.

Neil.
 
Neil McRae said:
not 100% sure but I thought the lifetime counter came in some time after IMDN had come out? Have you the history of the game are you sure abut the number of plays? In any case its a ****ter for sure.

Neil.
Click to expand...

Hi Neil,

I bought the game from a top bloke who is on this forum and know that it was immaculate but unfortunately it was folded in my house for a year as I had a new kitchen installed into my old pinball room. i am not sure on the lifetime plays as I never look at that and definitely not on a very new game that is in super new condition. Only checked because I was so shocked it had happened with such a new pin.
no replacement boards in the UK, and apparently because of shortages, pins to make, none on the horizon either
 
myPinballs said:
Taking a look at some broken ones I have later to see if I can sort out. Seems sensible to spend sone time on these now
View attachment 151280
Click to expand...

Well, 10 hours in and no further ahead yet. Still both broken. However i have learnt more.

The first one has a short on the output for 5v, but will power on the 6v line and output 3.3v ok to with the yellow led blinking. Unfortunately the 5v regulator gets hot because of the short on the 5v line. Therefore 'node board not found'

The second one has a short on the 6v line so no leds apart from the red ones for 48v. Changing the 6v switched mode regulator makes no difference as the short is on the output side somewhere. Therefore 'node board not found'. There are also some interesting design choices for enabling the regulator in the first place...

This seems to be the common problem on these frikin boards, you get a dead short on one of the output voltage lines but its near impossible to find what component is causing the short. The regulators either shuts down because of it, fail themselves or get really hot. I've now had the same issue on the 3.3v line, the 5v line and the 6v line. Never seen anything like it.

Any suggestions on how to find a dead short on a board, other than having to go through every decoupling cap on there one at a time??, and that isn't a guarantee as some chip could fail i guess to internally with a dead short, though these problems i've only ever seen really with caps and on arcade boards mainly.

Not bloody good.....

Going back to fix some donkey kong arcade boards for a break!!

Some pics! Test rig!
AD97447B-3817-4670-859F-9FDB70D63F2B.jpeg

Swapping regulator
E19F63EE-7DF2-4854-AF73-CF1DC6F884C2.jpeg
0803BF70-D1C9-4C02-88AA-D37029270800.jpeg
 
Last edited:
CHRIS B PINBALLS said:
You must be bored
Click to expand...

Worth spending the time to try and help people now there arent any new ones available and i dont like having boards on the list that are black boxes. If i can repair a percentage of them then that has got to be a good thing for us here in the uk plus it avoids the usa ordering and wait process for any that are over there. Now to update my repair note files :)
 
You must log in or register to reply here.
Back
Top Bottom