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#3 Williams Star Trek TNG

Menace

Well-Known Member
Staff member
Nov 14, 2012
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Santiago de Aurora
Alright, last one for tonight... This one was a little interesting because there is history between this particular game and myself.

At some point last year I had the pleasure of meeting Warlock (one of the nicest, most sincere people you could ever meet I might add) at one of the many pinball gatherings, and during conversation we got to talking about grail games, one of which for him was STTNG. I immediately gave him my thoughts on the game, and how much of a freakin' nightmare it can be to get / keep running, given all of the opto's and various other doo-dads "The King" crammed into this game. He made a mental note, and carried on. Fast forward a few months, and I get a message from Scott about a STTNG that popped up for sale and asked me to look it over and give him my thoughts as he was very interested (as it had some technical issues the current owner couldn't solve). It just so happens the game in question had already been through my hands a couple of years prior and I completely (and when I say completely I mean COMPLETELY) re-worked this game from top to bottom for the owner at the time, so I knew all of the work I had done to it but couldn't vouch for anything that might have been done by subsequent owners. At least I was confident the game would still be an excellent example to work from, and gave Scott my seal of approval to purchase.

Off the top of my head, I had completely shopped the game out, fixed all of the operator hacks to all of the trough and subway opto's (most of the connectors had been bypassed) replaced the subway divertor assembly as the op had busted the original, fixed a bad coil on the divertor, replaced both cannon loom harnesses, replaced the cannon position switches with the ones WMS released a TSB for, replaced a busted and poorly repaired cannon motor arm, modded the cannon lamp domes, had the Borg ship custom painted, installed LED Flashers in the Borg ship, Cliffy's, lane extenders, new sling plastics and I'm sure I'm missing stuff... The game was a disaster when I got it, but it cleaned up REALLY nice.

20121123_214954.jpg

So after changing hands about 3 times since I worked on it, the current owner was stumped with the latest issue and was done with the game. From what I was told the game wouldn't load the balls into the correct troughs on start-up, and it would just keep cycling the balls. Before I arrive at Scott's I'm already worried this is going to be one of those repairs that has me going in circles... So once I get there the first thing to do is check the subway and divertors. Lift the PF, and actuate the divertors by hand only to find one of the two is stuck. That might do it. Disassemble the stuck divertor to find this...

20121123_220730.jpg

BAZINGA!! The coil and sleeve is completely melted inside! So I immediately open the head and go straight to the Aux-8 PCB (found on games like STTNG and IJ, and maybe a couple others) and I notice it's not the original PCB, but a Rottendog replacement. I thought that was a little odd as the game was all original when I last worked on it. Pull the Rottendog PCB out, and as I suspected the driver transistor for that coil is toast. While this is going on, Scott was looking in the game and found the original Aux-8 PCB in the coin box. Now at some point someone else had repaired this PCB, but after testing all the transistors and diodes on it everything checked out ok. I re-worked a couple of the previous repairs to my liking, and installed the original Aux-8 PCB back into the game. (again, this is something I unfortunately didn't think to take a pic of at the time)

Now at this point we didn't have any spare coils laying around to replace the melted one, and it was after midnight on a Friday so I couldn't just get something from SB, but I didn't want to leave Scott's place without testing the repair. This way Scott could order up a replacement coil, and install it himself and know that once completed his game would be back up and running again. So what I did was disconnect the second subway divertor coil and swap it in to the suspect location and connect everything up. Fired up the game, put it into test mode and tested that coil, and worked like a charm. :)

There was another issue with the left cannon never finding "home". The previous owner was convinced it was an issue with the cannon loom, but it was still in as new condition from when I replaced it years earlier. Knowing the theory of operation really helps in these types of situations, and after inspection I found that the plunger was actuating and not retracting, and when this happens it blocks the opto's and the game thinks there is a ball stuck in the cannon. When this happens the cannon will constantly cycle back and forth until the optos are clear. The plunger wasn't binding on anything, but it turned out it had become magnetized and the bell end of the plunger was sticking to the metal coil bracket. Made some minor adjustments to try and minimize contact, and it seems to have done the trick as Scott hasn't mentioned it being a problem anymore.

Scott was able to get his hands on a new coil not long after that, install it in the missing location and hook up the wires as I instructed, and the game has been playing flawless since.

Grail pin aquired, repaired, and a happy new owner. :cool:

D
 
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WARLOCK

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Nov 14, 2012
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Thank you Doug. Only a few people know how important this pinball was to me. It was the ONLY pin I played at University.
Menace gives great advice if you are able to listen. I feel quite blessed that I have implemented 50% of the most important
advice he has given me in the last year or so. I wish I had listened to the other 50%, but I am new, so what can you do really?

This game defines an era of life for me! I understand those who like it, and those who don't; trekkies, everyone else. BUT:
This game was one of 3 or 4 games I just HAD to have. Period! It is the ONLY DMD that can't leave my house. Thanks Menace.

Doug made this a great pin, long before I was ever around pinball. It is a great pin for players who like this style of game play.
Menace knew this was "THE" machine for me to purchase, and gave me permission to do so, and would then help in fixing it.

When Doug offers good advice, I do listen, and I hope I am more than 50% receptive to the advice; because he is more than
100% confident in his recommendations for what he knows well, and what should work for you, not for him.

Thank you very much my friend. You already know how much.
 

Chris Bardon

Well-Known Member
Nov 15, 2012
1,301
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Mississauga, ON
I'm really glad this worked out for you guys-I gather that the rewire I did on the 50V from the aux driver board back to the circuit did the trick? Just to close the loop on this, I had the game for maybe three months before one of the diverter coils melted after the game was on all day for a party. Replaced the coil-same problem. Checked the board-bad transistor on the aux driver board. Replaced the transistor, it blew again. Read about the "tieback diode" issue, which is basically a single thin wire that carries 50v from the aux driver board back to the 4 coils on that circuit. Checked the wiring, and found it intact, and managed to read 50v where it was supposed to be.

At this point, I enlisted some help from Nick, and got the original board cleaned up, and even tested it in a TZ first to make sure it did what it was supposed to there. Everything seemed fine, so I took it home, put the board in STTNG, put in the new coil, turned on the game, and the board caught fire :) That's when I ordered the Rottendog replacement-I figured something on that board was busted beyond repair, so if I could get a $50 replacement, then maybe that would solve the problem completely. Got the new board, put it in, and THAT blew a transistor. Finally, Nick recommended rewiring the 50v tieback, since it could be reading OK on powerup, but if there's an intermittent connection issue, then it could be causing this same problem. Replaced the existing wire with a pair of larger gauge wires, and connected in two places as recommended in Clay's guide to have a backup connection. Replaced the bad transistor on the rottendog, which in hindsight was dumb. I didn't check the type, and it turns out you can't replace those with regular TIP 102s. Anyway, turned the game on for the last time, melted the coil, and then sold the damn thing. If I'd only tried the original board again.. :FP:

Anyway, in the end it's great that everything worked out. Scott got a game he really wanted, and I managed to learn a whole lot and still make out OK financially (really only out a bunch of parts).
 

mwong168

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Nov 14, 2012
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Great stuff Doug and sure Scott will enjoy this STTNG indefinitely. Has the mod been done to the stand up target for this game yet? I know Brock mentioned it was done on his old one which I own and said if a wire broke off that coil it can lead to a lot of collateral damage! Anyways, not it is a race between Scott and I to put in our ColorDMD which we both ordered back on Feb 8. Thanks Adriano and Walt for making a slight detour on their long way back from Allentown to pick up our parts.
 

WARLOCK

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Nov 14, 2012
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I received my Color DMD last night from Drano via Brewmanager.

Thank you Walt.
Thank you Adriano.

I am swamped at work, and believe it or not, STTNG is currently my "ONLY" pin set up at home.
That is crazy talk for someone who owns 33 pins, I am very certain. Quite unusual and unique!
That is the reality of the situation and the truth in these strange times.

Thanks to Menace again. The holy grail pin is up and running well, every single day since Doug touched it.
 

superjackpot

Active Member
Nov 19, 2012
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Mississauga, ON
Doug - Any way you could point me to the WMS TSB for the ST:TNG cannon position switches? Searches I done to date have not found this particular TSB.

Thanks,
 

Menace

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Nov 14, 2012
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superjackpot said:
Doug - Any way you could point me to the WMS TSB for the ST:TNG cannon position switches? Searches I done to date have not found this particular TSB.

Thanks,

I'll see if I can dig it out, but I can't for the life of me remember where I tripped over it. I think I ordered the "kit" from Marco tho... Basically it changed the home position switches on the cannons from the blade style to the roller rocker style switches.

I was right, I did order the "kit" from Marco;

http://www.marcospecialties.com/pinball-parts/A-19153

D
 

mwong168

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DRANO said:
No problem. Sorry it took so long :(

Hope you don't experience any issues.

I think my weak left flipper has been resolved so will see how it holds out for the next few days. STTNG seems to have a stigma of things not working and now the only issue I have left to resolve is my right canon coils not firing and when it did fire it would still think I didn't launch the probe. Weird and I am suspecting it could be related to the wiring harness such as a bad wire connection or break somewhere. I want to blame the Colordmd but removing it from the equation I still have these issues and I also confirmed last night that my GLM board is working fine in my friend's game as well.
 

tom_454

Active Member
Nov 28, 2012
115
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Ottawa
mwong168 said:
Has the mod been done to the stand up target for this game yet? I know Brock mentioned it was done on his old one which I own and said if a wire broke off that coil it can lead to a lot of collateral damage!

What is this mod of which you speak?
 

Menace

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Nov 14, 2012
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Santiago de Aurora
tom_454 said:
superjackpot said:
tom_454 said:
What is this mod of which you speak?

See the last post here. http://pinside.com/pinball/forum/topic/sttng-top-drop-target-questions

Thanks Barry. Interesting. Now I am going to have to read more about these tieback diodes - always learning in this hobby.

The tie-back diode is what we see on every coil, or on the driver PCB along with the coil transistor. It is used to block the reverse voltage that occurs when a coil is fired and keeps the junction in the transistor from being destroyed. (Its more technical than that, I wanted to keep it simple)

Hope that helps a bit.

D