Alright I have a dumb question. For the big cabinet capacitor can you use a snap-in 15K 25volt type which is typically used in WPC Driver boards similar to what's shown below? thanks

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Thanks. I tried this last night in my Alien Star which previously had 2 orange 6800 ufd 25v caps banded together (wired parallel) and for whatever reason didn't work? I was planning to buy a computer grade but thought I could get by in the meantime with the snap-in since that's what I had in hand. I'll have to troubleshoot tonight.

I have a follow-up to my earlier issue on my Alien Star. The other night I went to replace the 2 ancient orange 6800 ufd 25volt caps that were banded together in my cabinet. I replaced them with a single snap-in 15000 uhf 25 volt cap (non computer grade). After doing this it didn't work. When I turn the machine on it doesn't make any noise. I don't get any voltage on the Power supply board. I checked the 3 Bridge rectifiers in the cabinet and they are all within spec. I do get a small amount of voltage at the fuses but the game just seems dead.-I don't even hear any noise coming from the transformer.

I swapped in the old caps and soldered them in as they were before and it didn't make any difference. I also re-seated all of the connectors in the cabinet. the game is still dead. I checked all the fuses and they are all good, including the cabinet fuse. I even checked underneath the power supply where all the ground and power connections run and everything seems nice and tight.

Does this seem like something that will get fixed by putting in a new Cap or is there other issues? To me it seems like it might be an issue with the transformer or the power (wires) going into it? I know those rarely fail though and the only change I made was swapping in a cap (and then swapping the old one back.). is there a way to test the transformer? what other steps do you test if the problem exists somewhere before the Power board?

thanks!

Thanks. I've been studying up on pinwiki and Clay's guides but it seems like most of their troubleshooting steps are from the Power driver board onward. I thought it might be a problem with my cabinet fuse clip but I do get continuity. it's very odd!

I just ordered a capacitor online and it should get to me by Friday. Besides that, the bridge rectifiers, the fuses and transformer, is there anything more to test before going to the Power board?

Alright, I feel like a dumbass.... The issue was caused by an interlock switch which was located near the tilt bob in the cabinet. Do most games of this era have an interlock? it's not activated by the coin box or the coin door which I found a bit odd. -the switch is angled towards the back of the machine.

Will this capacitor be suitable for the cabinet? I tried it and the machine doesn't boot and has a lot of static noise?

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Capacitor is working just fine now. Must have just taken a while to charge up and get acclimated in the machine.

What did I do? I was closing the backbox light panel on my Alien Star when all of a sudden I heard a loud "pop" and my displays went dead. Checked fuses and F3 was blown. popped in another fuse and the displays came back on (player 3 had a segment out) but within a few minutes I heard another pop and the fuse blew again and displays went dead. I then unplugged all displays but player one and it powered on and was fine. Did the same for the others and determined that player 3 was the problem.

Anyone have any suggestions as to what happened and what I can do to fix it? If something pops like that is it usually a capacitor? Thanks!

Does anyone have an extra working 7 digit display I can buy? Maybe left over if you upgraded displays?
One of the displays in my Alien Star went out. Pn: ma238 or C-21390.

Are these easily fixable? If I leave this display plugged in none of the displays come on but if I unplug it everything works. I replaced the main 1ufd capacitor and the resistor tests fine on the display. I moved it to the four player slot so I can at least play 3 player games but it would be nice to get everything working. Any suggestions on what to try? Thanks!

Sounds good. Thanks for checking!

I'm shopping out my Diamond Lady and putting it back together but I'm unsure where these two metal brackets go? Took lots of pics but not good enough apparently. Any one have any ideas? Thanks!

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You're exactly right. Thank you! Now my ramp will be better protected.

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I've been working on getting my Diamond Lady working. Had it playing with the exception of a few switches (3 of the center drops and right sling). In the middle of a game it started going berzerk and a bunch of switches started going off and the score started going up rapidly. After about 20 seconds I shut it off. Now after powering on it boots fine but I'm unable to start a game. None of the switches work and show as open in the switch test. Any idea of what to try next? Ground mods were already done on the game. Thanks!

I finally got my Diamond Lady playing but the issue I'm having is that that my coils don't seem as snappy as they should be.

I can make all the shots but even with completely rebuilt flippers they seem to be on the weak side. And my right target bank sometimes has trouble resetting even after cleaning/rebuilding it. Even pops and slings seem like they are at about 80% of where they should be in terms of power. I have good 5V and 12V going in to the boards.

Any ideas of what I should be checking and what the likely culprit could be? thanks

Thank you for the advice!

I did re-flow the solder on the ground PCB boards near the transformer if this is what you are referring to by the transformer ground upgrade? I haven't checked or replaced the rectifiers yet. i will check them tonight and report back.

I checked the rectifiers and they were all in the .4-.45 range which may be a little low? I ended up putting in new bridge rectifiers and a new cabinet capacitor and it seemed to help with coil power. It may still be a little weak but the drops have been able to reset everytime so far and everything seems a little peppier. Thanks again the the recommendation.

It may just need a new pot. Those are notoriously flaky. There aren't many components needed to rebuild so it would probably be worth doing

Sent you a pm. I generally use the little disc capacitors just because it's clean and easy.

As long as you play your games semi-regularly the disc capacitors work well and are much easier to install. I use the same model that Mad_dog recommended above. I drill a small hole for the negative lead and put the positive lead in the + hole. then run a jumper under the board to the negative hole.

Update. I checked against the manual and the wrong coils are installed in my right drop target bank and left slingshot. Coils that are far too weak compared to what's supposed to be in there. I think this will solve my issue.

My Alien Star was powered on in attract mode for maybe 30 minutes and then the relays and lights started flashing. Now it does this immediately after power up.

I checked voltages and they appear to be fine. I have solid 5, 8, and 12 volts and my high voltage is slightly below the TP voltages. I also tried re-seating connectors but that didnt help. Anyone have any ideas of what to look at next? Thanks

Thank you. I replaced the orange cap and the bridge rectifiers a few years ago when I first got the game along with doing the ground mods. The MPU is a Swemmer that I bought new at the time. With that being said I agree that even though it's a basically new MPU that it does seem like it could be a MPU chip or connector issue. I'll try reseating the chips you recommended and try booting it with the driver board disconnected and let you know if I have any success.

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It does have an aftermarket replacement PS board. Voltage readings for the test points are as follows along with the suggested TP voltage:

TP1 14.83 (12)
TP2 (GND)
TP3 5.08 (5)
TP4 8.47 (8)
TP5 86 (70)
TP6 56 (62)
TP7 39 (42)

Would TP6 and TP7 testing lower than the stated board values have any effect on the game booting? TP5 seems a bit high.

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thanks. The relay clicking and lights flashing is immediate upon power up and is constant. It doesn't seem like it is booting fully. It just keeps going and all of the relays in the game cycle including those on the coin door interlock. The displays flash and the center red insert on the playfield flashes as well. I don't know if the numbers on the display mean anything or not.

Does anyone know what this little daughter board is for? If I unplug just this board the game doesn't continually cycle the relays and flashers.

The problem does seem isolated to the MPU. I disconnected the other boards and the problem still exists.

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If I unplug the reset board the game does seem to boot up most of the way (the game over light flashes on the backbox) but I'm unable to start a game or get into diagnostics. It doesn't seem like anything is locked on and it still doesn't boot up clean even if I disconnect from the driver and sound board. I think you may be right that it's a chip issue. I've tried reseating but I don't have replacements on hand to swap in to test.

thanks for the help.

Thanks guys. I have it disconnected now and its no longer cycling the lights and relays. It seems like it is at least partially booted up but I still can't start a game. I think one of the chips on the MPU must be causing issues in the boot cycle.

It doesn't seem to be coming up clean. I get weird numbers on the displays and the high score doesn't toggle. I don't think it's booting up all the way. I'm unable to add a credit.

I have had the trough switch issue in the past when trying to start a game. I don't think that's what's at play here.

thanks!

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