Hi

I'm fixing a STTNG that I bought not to long ago. I'm trying to deal with both cannons that are moving way to slow in game mode but move perfect in test mode (with no load - opto beam unbroken).

I've searched around and found more topics on this matter with a solution saying the shafts in the cannons should be taken apart for cleaning and thereby removing the problem. So I've done just that but still struggles with the cannons being to slow.

I found that the cannons turn slow as a result of closing the opto in the loading part of the cannon. So if I break the beam the cannon will slow down and if I remove the object breaking the beam, the cannon will regain it's speed. I guess you can say this proves that it's NOT grease slowing the cannons. I mean - would anyone suggest that the grease is reacting to breaking the beam on the optos

I've also found an solution that says it could be the transistors controlling the cannons. And others saying it could be the 12v on the power driver board. To target that, I've swapped the PDB with another pinball - but this has not cleared the problem. I guess this eliminates the PDB as the source of the problem?

I've also swaped the opto board in the play field. That also changed nothing. Thinks we can rule out the opto board also then?

I've tested the cannons in the test menu and both register their switches correct as they turn. So the physical switches under the cannon also seems to be fine. I've also looked at the switch matrix and found that all optos registers as they should.

So - I'm stuck here hoping some of you can point me in the right direction.

Quick recap:
Cannons move slow in game. Moves perfect in test mode if there is no load (opto beam is not broken). PDB has been swaped. Opto board has been swapped. Grease on the shaft of the cannons has been removed. So what's next ??

Boiler415 Yeah - this makes no sense to me. But - perhaps I can ask you, which version of the ROM you are running? Looking at the reply from twinmice the ROM could be the next place to do some testing.

twinmice If you have a chance to find out which version of the ROM was working without problems, I would be pleased to get that information.

Anyone else that owns a STTNG reading this topic - please let us know the version of your ROM and if cannons are running as expected.

Thanks!

Hmmm - looks like I need to start another topic to get STTNG owner key in there ROM version and if the cannons work as expected.

So - I'll keep this one open to continue the search once I have more feedback from the other thread.

Boiler415 - I agree, but - It's has to be at times where the opto is "in play". I mean - you can block the opto in test mode and the cannons will run at full speed anyway. It's only when blocking the opto and the game cheks for a blocked beam you will see that the cannon run slow. Or you can say - it's only when the game is out of test mode you'll see the slow cannons when the opto is blocked.

Anotother thing I tried was testing the cannons in the MARK and HOME switch test. As you know - this is a separate test option in the test menu. In this menu I put a ball in the launcher and activted the "coin door closed" button to have the solenoids active while testing. In this mode the cannons ALSO run at FULL SPEED even with a ball ready (opto blocked). When it reaches the MARK position on it's way back to HOME, it will "empty" the launcher in the same way it's done when the game runs and you havn't launched the ball.
My point - here the cannon runs in full speed with the opto blocked. And we know it test the opto because it will eject the ball when the cannon is heading home. Yeah- strange !!!

All I'm saying is - I havn't ruled out the ROM thing yet. I follow what you say and we will love to have your feedback with the metering figures when you have had time to look into this.

By the way - I run on a LX-7

Agreed - actually think that's what I'm doing.

Well - I'm sure you'll agree that it's logic controlling the cannons. So I don't see how that can be ruled out.

As written in previous post - I started by taking the assemblies apart, cleaning and greasing. Reading on you'll see that I also tested the cannons in different situations.

Please tell me - how the opto can influence the speed of the cannon when NO WEIGHT is added to it? Also explain how cranks, slack and bindings can be of influence in game mode where as they do NOT impact the speed of the cannons in test mode?

I appreciate your time and input - but I don't see your arguments adding up to what I see here. What am I missing?

Ok - let us skip the discussion about physical vs. electronic impact on this issue. We are on the same page talking about "other points to consider". I'll be back with some figures in a few weeks. As for now I have other "things" I need to attend.

So it's not forgotten - just delayed for a few weeks before I can get back with more details.

xTheBlackKnightx and ForceFlow - point taken. I'll be back

Back from vacation

As suggested, I took out some readings of the cannon in game mode. Here is what I saw on my multi meter.
The readings was taken under the PF directly on the motor itself.

The game started in power off.
I turned on the game, and the motor gets just above 10v. The cannon moves in a nice flow and speed.
I start a game and put a ball in the cannon launcher. The cannon moves slow and the multi meter reads 4.8v. The second i launch the ball the meter reads just above 10v and the cannon speeds up to "normal / expected" speed.

So what can be concluded by this test?
To me it sure sounds like a electrical issue and not a "dirt" / wear issue? But I'm open to suggestions.

Video here: https://1drv.ms/v/s!Ark__7XSDktRg75oVlN6yy7KSNio5w

Ok - new readings. This time taken directly from the PDB. I've attached the probes to J118-2 and J126-2. This is correct - right?

I start with the game in off.
I power on and I see close to 12v sendt to the cannon. It moves i a nice flow and speed.
I then start a game and put a ball in the launcher. The cannon moves slow and the multi meter is jumping in values between -2.5v and -3.5v ?!? Once I launch the ball the meter reads close to 12v.

Does this make any sense?

Video here: https://1drv.ms/v/s!Ark__7XSDktRg75pH1rpUerTGcpRBA

right_gun (resized).JPG

Not sure I understand what you mean.
Do you want me to unplug the motor and the read the numbers from J1 or J2?
I mean - if I unplug the motor I can't see how it runs with the opto open and how it runs when opto is closed.

But - if read the multi meter of EMI board J2 - with motor connected - I'll get the exact same numbers as on the PDB. That beeing 12v when nothing is in the launcher and between -2.5v and -3.5v when the ball is in the launcher.

Ok - new finding !!

I found out, that if i measure the voltage with the negative probe connected to ground wire in the cabinet, it will read just above 13v on J2 on the EMI board when cannon is idle. Once the cannon is loaded with a ball (in game mode) the multi meter will measure the voltage just below 12v on J2 on the EMI board.

Can any conclusions be made based on that?

Pin_Guy Well - that's interesting data !! So someone programmed the ROM and added an "off-pause" to the transistor to slow down the cannons. Nice finding !

In my case - I'm not pleased with the slow speed, so I need to take some of the other options you have listed. Revert to an older ROM is most likely what will happen because on my game the "slow" speed in L7 is close to being stopped which is no fun either.

I'll be happy to take a look at the code if someone can provide the source. I'm not going to start with the binaries and work my way through the code. That will take forever. But if someone has the source and can tell me where to find a suitable programming tool / environment I'll give it a go.

The last option to build a secondary drive module is out of my skills. So I'll not be able to see that as an option in my case.

Eddie When you say a flipper can become weak when another motor is active - do you then mean the flipper in the game, or are you talking about the game (flipper machine) as a hole? Because I don't see any weak flippers in the game. They work as expected. But the speed of the cannons are slow. How do you see opto error and speed of the cannons as being related? Am I missing something here?

I'm asking because you might be on to something here. So it's an interesting point!

Thanks for posting this for comparison. I can say that my cannons move slower than this. But do you know which version of the software (ROM) is being used in this game. As suggested in another reply, it might be the pulsing of the cannon that slows it down which is done in version LX7, so if this is another ROM version it might not be comparable.

I took a similar reading on my game - and sure enough - my scope also shows the pulsing in game mode.
So we know that pulsing is going on - but when you recommend keeping the game as is, and I still think the cannons are way to slow, I think that somethings doesn't add up. This is my second STTNG, and I'm sure the cannons on my first STTNG moved way better. I'm almost sure that one also ran LX7.

I'll post a video later on so you can see the speed when the game is running.

There's another suggestion about the influence of failing optos making an impact on the motor in the gun. I'm going to look into this as well to see if that's part of the problem too.

I've uploaded a video on the link below. Please let me know what you think of the speed.

For your information I've changed the optos in the cannon before taking this video.

I also have a ROM (version LG) at hand that I can try. But I'll let that be for now, until I have your feedback.

Please pay special attention to the part of the video where the cannon has a ball loaded and has reached it's turning point and heads back home.

Video is found here: https://1drv.ms/v/s!Ark__7XSDktRg75r7caPniS-WRx34A

Pin_Guy Wow !! That's more like it !!!

Guess changing the motor and gearbox could be something to consider.
Argh - if only importing stuff from the U.S. was not so expensive ...

I'll give it a thought. Might also be that I test the other ROM before I go any further. Could be fun to see what that can bring into the equation.

I have two things left for now.

1) Try the LG version of the ROM. Check if it also pulse the cannon. If not and speed is OK I'll have to consider if I can live with then LG ROM or if I need to fix the real cause of the problem.

2) Disassemble the gearbox. Clean and regrease. See if that fixed the problem.

If none of the above work I'll have to "bit the bullet" as said by Pin_Guy

Hi everyone

Ok - a final note on this issue.

I tried changing ROM - no effect.

The gearbox was drilled open (not by me ). It was degreased cleaned and greased again. It was reassembled and after that it was the best moving gearbox ever seen in a STTNG But still no cigar !!

At that moment everything had been tried except putting in a new motor. So - yeah - I had to "bite the bullet" and order two new cannon & gearbox assemblies from Marco. Upon installing the new hardware the motor and gearbox was separated. I was amazed to learn how hard it was to spin the gears and I had serious doubt that the motor would ever be able to move the cannons with the all new gearbox. But guess what - it did just that. And with no problem at all !!

So - I'm quite sure that the gearbox was never a problem. The original gearbox was running way better (or at least with more ease) than the new one. And still the new motor had no problem spinning the new gearbox and cannon in a perfect tempo.

Cut short - in my case it was the motor causing the problem on each of the two cannons. The motor would do just fine when NOT being pulsed. In other words when in game mode and with a ball loaded the software will pulse the cannon and with a weak motor this will have a huge impact on turning speed.

Thanks to everyone for all the help and suggestions. Took a while but now that it's working I can only say it was worth the effort (and money !!).