Anybody repair Sega Star Trek boards?

TheEnglishTear

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I did something stupid and fried some components on the board...at least it smelled that way. No visible damage. This sucks. Anybody repair these boards?
 
I did something stupid and fried some components on the board...at least it smelled that way. No visible damage. This sucks. Anybody repair these boards?

What did you do? Which board do you think you fried? Maybe it's something simple, maybe not but you never know.
 
What did you do? Which board do you think you fried? Maybe it's something simple, maybe not but you never know.

Well, I unplugged the noisy fan from the cage at some point...hooked it back up not realizing that I hooked the plug from the transformer (AC) into the connector going to the 10 DC out...which must have went straight to the cage boardset. No visible damage but a strong smell on the top two boards (board with bunch of connectors and the one on top of it) so yeah, I must have sent ac voltage to the power supply through the dc out, and thus sending it to the boardset. Huge huge mistake. And I WAS having a good night :/
 
Ouch, well lesson learned. It's a good idea to take plenty of pictures before you unplug any connectors and label them so you avoid what just happened. Hopefully the damage isn't too severe.
 
Ouch, well lesson learned. It's a good idea to take plenty of pictures before you unplug any connectors and label them so you avoid what just happened. Hopefully the damage isn't too severe.

Yeah. I have no idea what that 2 pin molex connector coming from the dc out is actually for...it isn't supposed to hook to anything is it? I should have just got out the meter instead of just plugging stuff in anywhere. So dumb. But yeah, a mistake I won't make again
 
Yeah. I have no idea what that 2 pin molex connector coming from the dc out is actually for...it isn't supposed to hook to anything is it? I should have just got out the meter instead of just plugging stuff in anywhere. So dumb. But yeah, a mistake I won't make again

Off the top of my head the only 2 pin molex coming off the DC power supply is P 12 which supplies +5 volts to the coin door lights. If thats it then it looks like you put 120 Volts AC on the 5 volt line. :( each plug should have a number put on the connector with a black sharpie.
Which Star Trek cabinet are you working on, Dedicated, convert a cabinet,kit or cockpit ? The kit version has a 44 pin edge connector on the top cover of the card cage. The others have the 3 molex plugs on the side of the card cage.
 
Off the top of my head the only 2 pin molex coming off the DC power supply is P 12 which supplies +5 volts to the coin door lights. If thats it then it looks like you put 120 Volts AC on the 5 volt line. :( each plug should have a number put on the connector with a black sharpie.
Which Star Trek cabinet are you working on, Dedicated, convert a cabinet,kit or cockpit ? The kit version has a 44 pin edge connector on the top cover of the card cage. The others have the 3 molex plugs on the side of the card cage.

It's a weird stern convert a cab. It does have that edge connector. So the cpu and sound board smelled funny...is it possible I got lucky and only two boards were affected by my screw up? Seems to me since they are all connected via slots that all of em were affected, I dunno. Is it repairable?
 
It's a weird stern convert a cab. It does have that edge connector. So the cpu and sound board smelled funny...is it possible I got lucky and only two boards were affected by my screw up? Seems to me since they are all connected via slots that all of em were affected, I dunno. Is it repairable?

Yea they made a kit to convert Stern games. Well if you smelled something then something is damaged but how bad depends on how long it took the main 5 amp fuse to blow if it even blew. I am sure it's fixable as long as theirs no damage to the PC board but it could have took out many components and yes anything connected to the 5 volt line could have been damaged so if you send it off to be repaired it's best to send all the boards so they can be tested.
 
Yea they made a kit to convert Stern games. Well if you smelled something then something is damaged but how bad depends on how long it took the main 5 amp fuse to blow if it even blew. I am sure it's fixable as long as theirs no damage to the PC board but it could have took out many components and yes anything connected to the 5 volt line could have been damaged so if you send it off to be repaired it's best to send all the boards so they can be tested.

Thanks again for the advice, no fuses blew btw. I shut it off as quick as I heard the weird sizzle noise...hopefully everything isn't fubar. Mongo suggested I troubleshoot the boards in my eliminator cab. I wouldn't think a damaged board would damage other damaged boards in the cage while testing, would it?
 
Be sure to read The Sega/Gremlin X-Y FAQ written by: Mark Jenison
http://www.darkstararcade.com/mars/faq/SegaXY_FAQ.txt
Wile you can test your boards in your Eliminator game the only 2 boards that are a direct swap are the X-Y timing and control boards and if you put them in your Eliminator and they are bad then they could damage your monitor. Star Trek and Eliminator CPU boards are the same but you would have to swap the special chip (protection chip/slapstick) at U21 and an EPROM at U25 as they are specific for each game and Eliminator dose not use a speech board and the sound boards are different too so you can swap some boards around but you cant test every board. If you had another working Star Trek board set then their would be no problem.
I would start by checking the power supply voltages from your Star Trek power supply with your boards disconnected and look at all your boards for any blown/burnt components. One step at a time.
 
I guess that's my question and problem. Just by looking at the boards nothing looks burnt. I had a thought of getting a ic tester but that would require removing every ic from the board one by one in order to test it. I have a ic probe but don't really know how to use it


Be sure to read The Sega/Gremlin X-Y FAQ written by: Mark Jenison
http://www.darkstararcade.com/mars/faq/SegaXY_FAQ.txt
Wile you can test your boards in your Eliminator game the only 2 boards that are a direct swap are the X-Y timing and control boards and if you put them in your Eliminator and they are bad then they could damage your monitor. Star Trek and Eliminator CPU boards are the same but you would have to swap the special chip (protection chip/slapstick) at U21 and an EPROM at U25 as they are specific for each game and Eliminator dose not use a speech board and the sound boards are different too so you can swap some boards around but you cant test every board. If you had another working Star Trek board set then their would be no problem.
I would start by checking the power supply voltages from your Star Trek power supply with your boards disconnected and look at all your boards for any blown/burnt components. One step at a time.
 
As I understand it, you applied AC between +5V and GND pins.
I would take each board out individually, and ohm 5V/GND to find any short on that board. I would guess the input caps were affected and they may or may not have saved the ICs. (more "may not" than "may"). :(

Look for small holes in the IC packages. These might be found at the top of the package or at the side where the pins are. Got a microscope?

Example (damage may not be as extreme/obvious):
426px-Failed_SMPS_controller_IC_ISL6251.jpg
 
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So you swapped the AC and DC cables on the power supply or plugged the AC directly into the cage?

Thats a bummer man. Lots of parts could have been damaged by either scenario.

If douglasgb doesnt take it on LMK. I could probably help out here.
 
5v to ground with power off, correct? And at what ohm value would it be considered a short?
As I understand it, you applied AC between +5V and GND pins.
I would take each board out individually, and ohm 5V/GND to find any short on that board. I would guess the input caps were affected and they may or may not have saved the ICs. (more "may not" than "may"). :(

Look for small holes in the IC packages. These might be found at the top of the package or at the side where the pins are. Got a microscope?

Example (damage may not be as extreme/obvious):
426px-Failed_SMPS_controller_IC_ISL6251.jpg
 
So you swapped the AC and DC cables on the power supply or plugged the AC directly into the cage?

Thats a bummer man. Lots of parts could have been damaged by either scenario.

If douglasgb doesnt take it on LMK. I could probably help out here.

Thanks, I'll probably go as far as swapping boards here with Mongo (so he can smack me in the head before I make another ignorant move). If that doesn't solve it I will hit you up for repair. Thank you for offering! :)
 
UPDATE! Mongo helped me try to narrow down the issue. But things may have gone from bad to worse. So what happened was I accidentally fed the power supply a/c power, which traveled down to the boardset, and I feared I screwed everything up in the process as I smelled weird things going on. Enter Mongo. He thought of testing my Star Trek boards in my elimator machine. He started with the Star Trek rom and cpu boards, with the eliminator x/y boards, but took the eliminator rom board, and sound board out. And Star Trek came up so we figured that the Star Trek rom and cpu were ok. Now here's where things got hairy. We slipped in the sound and speech boards from Star Trek. No sound, and after inspecting visually, a few chips had some tiny burn holes near the legs. But what made things worse was now, the image was distorted. So we took all of the Star Trek boards out and reinstalled all eliminator boards. Game seems to play fine in attract, but graphics are distorted (see pics), and when coining up and attempted to play, pressing buttons now had an effect on graphics which flicker with each button press as if it were a grounding issue. So my question now is, DID the messed up Star Trek sound board mess with the XY boards on both the Star Trek boards and now eliminator? I would suspect no but I suppose it's possible. What do you guys think?
 

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Well looks like a problem with the XY boards. Did you remove the XY boards? Sometimes I have had to reseat the boards a few times to get them working and that ribbon cable that connects the two boards can sometimes be a problem with bad sockets or the ribbon cables themselves can be bad. When ever I remove the XY boards I remove them as a pair leaving the ribbon cable connected and reinstall them together as a pair. It's to easy to bend the ribbon cable pins trying to install them with the boards in the cage. You could have a bad video RAM on the one XY board. Have you put the game in test mode? If you cant read the test screen the red LED on the MPU will flash out an error code if their is an error. You might get an idea on what to try by watching my video from the 29 minuet mark where I was having an issue with my XY boards.
 
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