Thanks guys. I'll look at the wires. Haven't replaced the harness. I'll look into that too.

I'm tweaking my STTNG to work flawlessly and I have a few questions:

1) The left VUK that feeds the wireform can sometimes hangup and not spit out a ball. You can hear it firing over and over again but no ball comes out (always it seems when I'm in a timed mode and I need the ball in play). Other times it works without issue. Any idea where I should be looking first?

2) During Borg Multiball, after the shields are down is it correct for all three balls to be launched back into play?

1) Enter test mode and take a picture of the switch matrix That will tell you where the machine thinks the balls are. Then see if that's where they actually are. If the ball is actually in the VUK and it's just not making it out, the mech might need alignment or cleaning?
2) I believe multiball continues as normal, but you cannot score jackpots while your shields are down. Left spinner recharges the shields.

I made the rookie mistake of not marking, or taking a picture, of the diverter before I took it apart.

Can anyone tell me how the diverter that I’m pointing to should be positioned with the power off? Inside or outside of the trough?

Also should the green coil below be a 25-1000 instead of a 26-1200?

1815AAD3-9580-40D2-A030-A17C9DB36000 (resized).jpeg

It should be against the inside wall.

https://pinside.com/pinball/forum/topic/sttng-owners-club/page/16#post-3349152

Just to help everyone, I found a good fix for the left canon going slow. I found that many were mentioning opening the gear box. Mine was just the shaft of the canon. It is literally a 15 minute fix.

Steps:

1. Disconnect left opto and canon light under the pf and feed a good portion of the wire toward the upper PF. You need this to get the cannon out without soldering.

2. Take a picture of the underside, noting the positioning of the canon. Don't need this, but you never know, right?

3. Remove the 1/4" screw and washer at the base of the shaft.

4. Lower the PF and shimmy the post out, being sure that the wires do not become taut. The post will make it out with a little slack left. Mine did, ayway.

5. The shaft will have black gunk that is pretty tough to get off. I used fast orange pumice hand wash on a paper towel. Cleaned it in a minute! I used the same with a stick rag thing I have for the hole.

6. Greased the hole and edge of the hole with bearing grease.

7. Reassemble.

My canon is now like new without an annoying process of cracking open the gear box. Hope this saves someone time!

Dirty post:
IMG_20190614_145034 (resized).jpg

Clean post:
IMG_20190614_150111 (resized).jpg

If you have to do this you already know what the issue is...

https://pinside.com/pinball/forum/topic/sttng-owners-club/page/5#post-2938877

FWIW, I personally wouldn't do it this way and those of you that follow my posts already know I am very detail oriented; I would remove the cannon and wiring from the game (4 screws + 3 connectors), then work on the mechanical stuff out of the game since I would likely be using strong solvents to remove all the old grease and wouldn't want to risk getting any of it on my playfield.

Of course I would them tumble all the metal parts to get them shiny and new looking as well

At the end of the day it's your machine and it's entirely up to you on how you want to work on it.

The following aren't my pictures but if ou are going to take it apart to clean and re-grease it, this is what the parts should look like before you put it back together:
https://pinside.com/pinball/forum/topic/sttng-owners-club/page/5#post-2936932

I'd prefer your method, but I prefer 15 minutes over hours. I also prefer not to take things apart if I don't have to. To each their own, but I prefer more play time!

I just finished stapling the pop bumper lamp leads into place and soldering the wires back onto them. What a pain. Glad it’s done. Thanks Pin_Guy for the detailed post with pics, it came in very handy.

So @play_pinball's machine just doesn't want us to play it. The borg lock opto wasn't working. Managed to nail that down to a faulty LM339 (there were 6v and 12v going to both of the correct pins but no 12v output). I swapped that out but once putting it back into the game the 12v supply was now 7v. I checked both sides of R59 and one side was 12v while the other was 7v. I checked the resistance of R59 while it was in the machine and connected and I swear it said 10k ohms which seemed weird (wouldn't a lower resistance mean LESS of a power drop?) except that when I got it home it was 100k.

Anyone got any idea's here? Maybe the all knowing @pin_guy? Also does anyone know what wattage the resistors are? I only had 1/4w and 1w resistors and I thought the existing ones were 1/2w so I ended up putting in new 1w resistors (R52 didn't measure 100k so I thought that might have been the cause. But I got the same readings even after swapping it out. I guess R51 was throwing the readings off). 1w is definitely overkill but they should definitely last.

I assume we are talking about the CPU board. I'm looking at:
Williams WPC DMD Schematics 16-9473
pp4 (WPC CPU Board Sheet 1 of 1) [Page 2]

I assume you are talking about R59 connected to U19D (LM339):
U19DSTNG (resized).png

shows it's clearly at 1kresistor. Given it's in series to a comparator; I'd be surprised if it wasn't 1/4watt but I don't see any notes on that schematic page confirming that.

I think the 16-optoboard :
16 opto board.jpg

Yes sorry zaza is right. Opto 16 board.

To clarify further the specific LM339 portion was U2D (in the top right corner on the schematic. not shown in the pictures here). This is for the borg lock. Before changing anything pins 10 and 11 had 6v and 12v on them but there was no output on pin 13. After swapping the LM339 the 12v pin was now 7v.

I put another LM339 in incase I over heated it while i was putting the socket in. play_pinball likely won't pick the board back up until Sunday. I'm not sure what could pull the 12v down so low though.

I believe you are chasing a red herring here as this area of the board performs isolation and pulse symmetry of your column pulses which are in turn used to trigger the outputs of the LM399s. Any problems in this area of the board would cause significant issues (half the optos not registering) The signal you are reading at R59 is the column drive to half the board, you need either an oscilloscope or logic probe to see it.

pasted_image (resized).png

Well i guess if things are still broken (very likely) after he puts the board back in he's going to have to wait till my next paycheck when I can buy a new scope. I'm not lugging my archaic Techtronix 468 or whatever it is all the way to his place. I just need to get a more modern scope that isn't a literal boat anchor. It's bad enough lugging it up and down the stairs from my work bench area to the pins when I need to use it on a machine.

I’ve been steadily reassembling my game today. Can’t wait to get it done!
1E951703-34C7-4AB7-927B-0CE7ECFECE6B (resized).jpeg7D65F301-8C69-4ADB-A636-00E9CE798CEA (resized).jpeg

I didn't notice till much later that you'd actually found a page that has a parts list. Where did you find that? It's not in the manual i have and the 16 opto boards isn't in my WPC schematic books either.

It is possible that it may be fixed as the Borg Lock circuit does go through the U2 LM399 that I believe was replaced; if its still not working after that it may be beneficial to recheck all all of the connection to the opto board.

All parts information is in section 2 of the manual; the opto board is on page 2-15.

Silly me. I expected it to be along side the other 2 diagrams of the board.

In honor of Captain PicardDay; I'm doing a
16% off sale
for all STNG Products. Don't snooze... cause this deal disappears on Sunday Night my time.

There is a post in the manual and I can't find much information on it:

Does anyone know the length of this item?

pasted_image (resized).png

I can't believe none of the places that sell it list dimensions for it.

I did find this post. Maybe it'll be of some help.

https://pinside.com/pinball/forum/topic/needs-parts-help-from-fellow-sttng-owners

Be sure to get protectors for the alpha ramp. It gets the shit beat out of it pretty quickly.

Hi All,
I´m happy to find this forum and report in another proud owner of another ST:TNG machine!
My wife got it last September and the condition was good, but the seller bailed on us on the maintenance/warranty part. So we had to step up and learn how to care and improve it. Since I've replaced flipper coils (and parts), cleaned out and removed grease, change lamps, leds and so forth. Many useful tips came form Pinside (huge thanks).

Currently I am in the process of removing klugdes the machine got over the years and I encountered a significant problem: the low powered solenoid circuit was wired in a very funny way:

1) The pin J107-1 (in the WPC Power Driver board) had a wire running to the J4-1 (in the 8-Driver PCB) [Yellow arrows in the pic]
2) A high power (5w or 10 by the size) ceramic resistor was soldered to the ends of the fuse in F103 [Red arrow in the pic]

The game was working and the solenoids in this circuit were working both on the test mode and in playtime so I left them alone to research this later.

Recently one of the solenoids jammed and melted (Under Divertor Bottom). I got it out and swapped the Top Divertor solenoid to its position. Then the Top Drop solenoid stopped working and the resistor overheated and cracked. Obviously the fuse went with it.

Inspecting the machine I noticed the other Divertor solenoid melted and shorted. I got it out. I noticed the shaft of the Top Drop was stuck. Disassembled the Top Drop (A-14615) to clean and check everything. The sleeve in the Top Drop Up solenoid was melted, but the solenoid resistance measured fine (5.8 Ohms). I carefully cleaned and scraped all the old sleeve put in a new. Also I noticed the switch of the assembly had a short flap that didn't get pressed by the plastic flap in the Drop targets as it went down. I replaced it (and the diode) to make sure it would cause no problems in the future).

Now I disconnected the kludge cable, replaced the fuse in F104 and I'm waiting for new solenoid to arrive for the Divertors.

Does anybody know what was the purpose of the kludge? And should I restore it? Is it compensating for something amiss in the 8-Driver PCB?

Problems now:

1. There is no power (measured from J107-1 to the proper pins in J4) for the low powered solenoids.
2. The machine is stuck in a "locating balls" patter where it shoots a ball, it get in the top hole, gets returned by the Left Popper, falls in the bottom and the cycle repeats.
3. The right cannon cannot find home (unrelated?)

Any and all help is greatly appreciated.

Thank you very much in advance and I can post more details / info if needed.

IMG_2717.jpg

This is a fix for the 8 driver board tieback circuit; there are cleaner ways to do it, but the way yours is done is widely accepted by the community.

This should be an easy fix.

Williams used the tiny VIO/GRN wire connected to the dropdown target to provide the connection path for the coils flyback diodes; the problem is that vibrations from the drop target actions caused this wire to break resulting in no flyback circuit; without the flyback diode in the circuit, the first time a coil de-energized, the high voltage pulse is of sufficient voltage to destroy the drive transistor causing it to short and lock the coil on, the coils then melt from the heat before the fuse can blow; often times you also end up with significant damage to the 8 driver board.

EDIT: Do a search in this forum for "tieback" and you will find a lot of information on why this wire is there.

The drive transistors are shorted and are providing a ground potential to J107-1...this should cause its fuse to blow.

The machine is attempting to prestage balls to the 3 VUK's but cant since the subway diverters have failed.

Unrelated

Does anyone know if the Eaglemoss shuttle craft and Enterprise make for good “scale” replacements? Mines missing the shuttle craft and I’d love to add the enterprise for fun. Them not lighting is not a problem as I’m not worried about that.

DO NOT INSTALL THESE ... You must repair the cause of the missing 50V to the 8 driver board AND repair the blown transistors on the 8 driver board or you are going to melt your new coils...assuming the fuse isnt instantly blowing from the current board failures. YOu may want to take a good look at the 8 driver board and evaluate if there is any physical damage.

And for the love of God don't remove this this unless you like your boards extra toasty.

I think its too late

Hi Pin_Guy

I got it. Actually I re-read the manual and it is clear in the circuit schematic for the low powered solenoids (8-Driver PCB Assembly page, duh!). Should have been more thorough.

This means the resistor does not belong there, right?

Sure. Will do.

Is this due to the Tieback being disconnected? Because the fuse blew before my clumsy intervention.

Re: new solenoids:

Ok. I assumed as much. Besides visual inspection, is there any practical way to check these specific transistors? I have basic electronics knowledge, a multimeter and maybe an oscilloscope lying somewhere .

Thanks @Pahuffman, let's hope it's not too late.

I'll double check everything mentioned here and report back.

Much appreciated.

Hi Orko

I don't own this model, but the dimensions (https://www.wixiban.com/toys/eaglemoss-shuttles.htm) are close: the original is 9 cm length by 7 cm width. The Eaglemoss appears to be 7,0cm L x 4,1 cm W.

Hope it helps. The detailing an finishing of this model are quite good, still a bit pricey (considering you must buy a 4 model kit to get it) for me.

Cheers.

<trekkie speak>
PS: being the "Goddard" is more consistent with the decals of the machine than the original factory "Einstein" shuttle.
</trekkie speak>

958389e3-68f5-4fe5-bce8-1d00b1b84e9c (resized).jpg

God no, it looks like they may have used a fast blow fuse but put a resistor in parallel to make it a slow blow. If you put the right fues in and it blows you have another issue to repair.

Yes, of the tieback is missing, then the drive transistors fail and lock on the coils causing them to melt; unfortunately, the fuse usually doesn't blow until after significant damage has been done. Hopefully I'm wrong on this one.

Excellent, there is a very easy way to check these as they usually fail shorted. All you have to do is check the drive outputs to ground, with J4 disconnected from the 8 driver board, if you have low resistance to ground the transistor is bad. You can use J3 pins 2, 3, 4, and 5 for comparison.

pasted_image (resized).png

OK. I already replaced by the proper fuse. Will watch out for it.

You and me both.

Great! Will do.

BTW: I just went back to PinWiki on the #ST:TNG and saw the discussion on the tieback. Idiot. (http://www.pinwiki.com/wiki/index.php?title=Star_Trek:_The_Next_Generation)

Question: do you consider the pullback resistor suggestion there (to further protect the 8-Drive board) a worthwhile idea?

PS: I am not a fan of those IDT connectors, I plan on replacing them all with molex (trifurcon) equivalent ones. Any downside?

Cheers.

The logic behind it is sound, but I haven't done it to mine.

Both connectors have the exact same life expectancy ... 25 mechanical actions. I prefer the ORIGINAL IDC's but I'm in the minority on this. Let the debate bigin!

What type of fuse should be in the main power box? (not sure what to call it, the box with the service outlet)

I believe it’s an 8 amp, but is it slow burn?

How dented can the inside of the VUK get before the balls start getting hung up inside the VUK instead of shooting out? There appears to be some kind of sleeve inside the VUK. Is it removable? Is it replaceable?

So I just ordered an Eaglemoss USS Enterprise D “From all Good Things” purely because I love that ship. I don’t want to light it up or anything, but just have it looking like it’s doing a flyover. What would be a good way to mount it so it looks minimal yet glorious at the same time? lol

Re: IDC x Molex

So I'll bite: why do you prefer the original IDCs?

I have an extreme sttng project... Collected all missing parts except for the metal pf ball guide behind the upper flipper. Anyone know of someone with a parts playfield or spare parts?

They're easier to work with, have the same life expectancy, and since the wires side feed, the have the proper stress relief they were designed to have when connecting to the existing headers.

The main argument for the crimp connectors is that the IDC connectors fail...the problem with that argument is that when the connectors burn, they don't burn at the wire-connector point...they burn at the header-pin point and people tend to forget the age and life expectancy of these parts; with both connector types having the same mechanical life expectancy (25 cycles), there is no benefit to one over the other in this area. The big question is how many cycles can be expected on a board that is 20-30 years (age of all WPC boards)?

A single repair done perfectly can use up 6 cycles in a single repair.

1 - board removal from machine
2 - bench test connection
3 - bench test removal for repair
4 - connection for post repair testing
5 - disconnection from repair testing
6 - re-installation in machine

Hi @pinless,

Assuming you are talking about the line filter the manual states (Pg 1-39): Domestic Game: 8A N.B. (normal burn) and Foreign Game 5A, S.B. (slow burn)

I am a bit cautious because I've seen these units swapped and the fuses may change with different models. But I have limited experience with Pinball.

See a photo of the box in my machine (Foreign model) for instance.

Cheers.

FilterBoxFuse (resized).jpg

Hi Pin_Guy

Is the board mounted pin header also rated with a 25 cycles life expectancy? I ask because the dynamics of a board mounted conector are quite different from a wire mounted one.

Also there is a few things that I think about also:

1. A lot on these machines is not by "best practice" design, but rather either due to historical roots (inheritances ),
2. Some types of conector are open to a lot of misuse and improper handling, the IDCs are very vulnerable in this aspect IMO (obviously this does not apply if you are repairing/restoring it yourself),
3. In some countries the availability of IDCs is low/spotty at best, molex much less.
4. Stress relief is much less of a factor in the backbox compared to to main cabinet or moving parts.

But I am getting a sense that the differences might be "in the noise" here.

Once again thanks for your insights.

Thanks!!

Yes they are. The life expectancy is based on how many friction cycles it takes to wear through the plating, and applies equally to both the socket and the pin; once the plating is worn, the parts can deteriorate from both electrical and environmental factors. This is why its always recommended that BOTH the header and connector be replaced together whenever you have connection issues.
pasted_image (resized).png

Anytime, and you are correct, the differences are more personal preference than anything else. Realistically, the main thing I like about IDC's which I touched on but didn't go into details on is that I have the Pan-Con punch tools so I can not only re-punch an entire wire harness in a couple minutes, I can also rebuild an entire connector in around the same time it takes most to crimp a single pin

If anyone is interested, I found an extra set of ST:TNG Extended Exit Lane Ball Guides- Stainless Steel. They still have the protective coating on one side,,,,

$36.00 shipped USPS Priority, US only...

Mickspinball

Lane 2 (resized).jpg

ST Lane 1 (resized).jpg

I had some time to look at this again today and am at a loss. I spent a few hours with my new oscilloscope at @play_pinball's house and didn't really make any progress. I brought the board home and applied +12v and ground to J5. Using a multimeter I get 12v on both sides of R56 and R58.

However on the mirrored side of the board R54 and R59 have 12v on one side and .2v on the other. I went so far as to pull U2, U4, and U5. Even with those pulled there was no change. All the diodes test ok while on the board and all of the resistors read the proper values. There isn't anything else.

What am I missing here?