Star Wars Episode 1 light saber issue

Alky

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The light saber quit working and we replaced the transformer and the IC chip. It still refuses to work. Is there anything else that can cause this to not work or can the neon simply be dead?

Also is there anywhere I can buy a new neon if it is dead?

Any help would be welcomed because we are stuck.
 
If you have a volt meter, check that you are getting the proper outputs to the lightsaber transformer. That will tell you if it is in the saber or not.
 
If you have a volt meter, check that you are getting the proper outputs to the lightsaber transformer. That will tell you if it is in the saber or not.

We get our 12 volts without the transformer hooked up. As soon as we plug in the transformer the voltage drops below 1. I do now know the neon tube works because we rigged it with a 12 volt transformer from one of our lighting displays. For whatever reason the voltage just drops as soon as the transformer is connected.
 
the transformer

used to have a small neon manufacturing plant

wish i had a dollar for every transformer i had to replace over the years
especially the newer, smaller ones

looking up my transformer supplier in california...will update

ok found them here:
http://t2-neonpower.com/PRODUCTS/NEON_SUPPLIES/Neon_Supplies_list.html

unknown what is in there now. will look up in the schematic if i can find one
you probably need a 2000v 30ma with a 12v input
a 5000v will work but dont go bigger than that or you will burn out the tube

bet it will be under 30 bucks +shipping but who knows, its been a couple years since i bought any
 
Last edited:
used to have a small neon manufacturing plant

wish i had a dollar for every transformer i had to replace over the years
especially the newer, smaller ones

looking up my transformer supplier in california...will update

ok found them here:
http://t2-neonpower.com/PRODUCTS/NEON_SUPPLIES/Neon_Supplies_list.html

unknown what is in there now. will look up in the schematic if i can find one
you probably need a 2000v 30ma with a 12v input
a 5000v will work but dont go bigger than that or you will burn out the tube

bet it will be under 30 bucks +shipping but who knows, its been a couple years since i bought any

I think you missed the part where we already replaced the transformer..:) Unless you mean we need a different one. Thanks though.
 
I was going to post something then realized it's neon, not flourescent. DOH.

*faceplant*
 
By IC Chip, I assume you mean the ULN2803A that drives the neon transformer.

So you've tested the Neon using another transformer, or its own transformer with another 12v source? I'm confused by the post above.

So we've confirmed the neon is good (you've seen it light with the other transformer)?

If you have not tested the neon's OWN transformer, then that is the culprit. From your response above, it seems that you HAVE tested it using another outside 12v source.

If it only fails when connected to the pinball, but works with another 12v source, it seems that there isn't much else involved beyond the IC. Can you confirm the chip location of the IC you replaced? There are a few 2803's on this board.
 
By IC Chip, I assume you mean the ULN2803A that drives the neon transformer.

So you've tested the Neon using another transformer, or its own transformer with another 12v source? I'm confused by the post above.

So we've confirmed the neon is good (you've seen it light with the other transformer)?

If you have not tested the neon's OWN transformer, then that is the culprit. From your response above, it seems that you HAVE tested it using another outside 12v source.

If it only fails when connected to the pinball, but works with another 12v source, it seems that there isn't much else involved beyond the IC. Can you confirm the chip location of the IC you replaced? There are a few 2803's on this board.



It was the #35 IC we replaced.

Real quick Ill try to clarify.

Saber didnt work.
Ordered chip and transformer from Mad Amusements.
Switched transformer first to the new one.
Didnt work.
Swapped out the IC.
Still dont work.
Tested neon with outside 12 volts with new transformer installed.
Neon Lit up.
Im almost thinking that we got a bad transformer, but it worked with an outside 12 volt source. For some reason once its connected to the pinball 12 volts the pinball voltage drops to under . 05.
 
I found this online, anyone have a clue about this second chip he replaced? Or where I can find this guide he used?


Just wanted to share my experience in repairing the light saber on my
Star Wars Episode 1 machine. I followed Marvin's guide and found the
problem to be one of the two chips on the power board. The odd thing
was that there was always current up to the light saber molex
connector which at first led me to believe the transformer was dead.
After testing the transformer (by connecting it to my car battery) I
concluded that was not the issue. I went ahead and replaced both of
the chips (they cost about .60 each) and now everything works like it
should.
Hope this helps anyone who has this issue.
 
It was the #35 IC we replaced.

Have you manually grounded the neon while installed in the game? Take a test lead, and jumper the ground side of the connection to one of the ground straps in the game. This should be the black wire going to the transformer Molex connector. The neon should light. If it does, then you've still got a circuit/IC issue.

The next chip in-line upstream is the 74HCT574 at U34, if you are sure the new ULN2803A at U35 is good (you can watch the outputs with a logic probe while in test mode for the neon).
 
Im almost thinking that we got a bad transformer, but it worked with an outside 12 volt source. For some reason once its connected to the pinball 12 volts the pinball voltage drops to under . 05.

When you say "connected to the pinball 12 volts" are you talking about hooking it up correctly where it belongs (via the harness that is controlled by the ULN2803A), or directly to a 12V supply in the game? When hooked up correctly you realize the saber will not be on all the time, right? That IC controls when it gets switched on... it's off most of the time in attract mode.
 
Have you manually grounded the neon while installed in the game? Take a test lead, and jumper the ground side of the connection to one of the ground straps in the game. This should be the black wire going to the transformer Molex connector. The neon should light. If it does, then you've still got a circuit/IC issue.

The next chip in-line upstream is the 74HCT574 at U34, if you are sure the new ULN2803A at U35 is good (you can watch the outputs with a logic probe while in test mode for the neon).

It appears this is the case, please pm your paypal info and as soon as I go buy this chip in a minute and install it and it works I will shoot you 50 bucks over.
 
Well fuck. It didnt work.

I bought the chip from a local store that said it cross referenced though and I have bought transistors from them in the past that they said were crossed referenced and didnt work.

Can anyone verify that this chip which is a 74HCTLS574N is the same?
 
It appears this is the case, please pm your paypal info and as soon as I go buy this chip in a minute and install it and it works I will shoot you 50 bucks over.

While I appreciate the offer, I won't accept money for helping you. I'm more than happy to help in the public KLOV forum and hope others will help me when I need it. It is my belief that bringing money into it ruins one of the greatest parts about KLOV, the community aspect.

Personally, I don't like PM's asking for help, but the public threads can help countless other people who could have similar issues. Public brainpower is greater than one mind. :)

Shoot me some rep as payment. :)
 
Well fuck. It didnt work.

I bought the chip from a local store that said it cross referenced though and I have bought transistors from them in the past that they said were crossed referenced and didnt work.

Can anyone verify that this chip which is a 74HCTLS574N is the same?

I think LS and HCT are different. If you got LS, that would be a low speed version of the chip. I don't think anything in pinball requires the HCT, but I usually replace like for like, just to prevent any possible complications to the issues I'm working on.

Did you try grounding the black lead? What was the result?
 
After reading this thread I figure I'd give my two cents. You say the neon lights when 12 volts is attached externaly. Have you checked fuse 108 ? But if I recall if this fuse is blown you would have a few switch issues. For giggles I'd check the lines going to the neon in attact mode with a volt meter the 12 volt line should bounce around. Sounds like you changed the uln2803a and the other chip. Now I don't have a schematic in front of me but I can pull one from work since this is all I do all day is pinball. I'm almost leaning towards a broken wire in a harness. Check that line for 12 volts.
 
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