Cinematronics power supply - how hard is it to rebuild this thing?

jehuie

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Cinematronics power supply - how hard is it to rebuild this thing?

My game resets sometimes and I suspect it's because the +5 is a bit low. It reads a bit under 5 volts at the chips so I'm thinking that's why it works sometimes but not others...it's borderline.

So how hard is it to rebuild one of these? It's in my Rip Off game. Another option would be to temporarily throw a switcher onto just the +5 since the other voltages are all fine and see if it works solid then right?

Does anyone have any tips for a rebuild? Or know if there's a kit for this thing?

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Isn't that an old Linear power supply? All you need to do to recap it and it should be good to go. I really don't think there a recap kit for it. The large caps will be expensive to i think someone said it was 60 to 80 dollars to rebuild one.
 
Well I'm not having trouble with the breakers tripping now. So I should just rebuild it but be extra careful with the breakers then?
 
Thanks for the link. It doesn't look like the same power supply though does it? I've heard that one of them was really difficult to take apart. Maybe I'm just dreaming that. I'll find the schematics and get some caps and see how it goes.

That one's different. I think Cinematronics used three different supplies. One other thing to check is your headers/connectors. You can have quite a bit of voltage loss through fatigued connectors.

Edward
 
That one's different. I think Cinematronics used three different supplies. One other thing to check is your headers/connectors. You can have quite a bit of voltage loss through fatigued connectors.

Edward

That's a great idea to do first. I'll check reflow the pins on those and see if that helps before embarking on a full rebuild.
 
Ugh, I removed the solder from the header pins on the main power connector on both boards and reflowed new solder onto them.

Now when I power it up, not only does it reset but now the vectors are all wonky where they looked fine before. Errrr.
 
oh oh he repaired it and now it worse. Sometime those linear power supplies are cranked up to compensate for the poor connections. Once you reflow the pins you make a better connection and the voltages go up. check your voltages.

I wonder bumped the power supply and a cap is failing on you. That might explain the reseting issues.
 
oh oh he repaired it and now it worse. Sometime those linear power supplies are cranked up to compensate for the poor connections. Once you reflow the pins you make a better connection and the voltages go up. check your voltages.

I wonder bumped the power supply and a cap is failing on you. That might explain the reseting issues.

Just checked and the voltage is still low. It reads 4.92 at the chip level. Not sure what you meant in that second sentence. Are you saying that bumping the power supply could be causing resets? I don't think I bumped it.

So....is my next step to rebuild the power supply?

Also....here's a pic of the messed up vectors and how they look now. They were perfect before I reflowed the header pins. :(
 

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Just checked and the voltage is still low. It reads 4.92 at the chip level. Not sure what you meant in that second sentence. Are you saying that bumping the power supply could be causing resets? I don't think I bumped it.

So....is my next step to rebuild the power supply?

Also....here's a pic of the messed up vectors and how they look now. They were perfect before I reflowed the header pins. :(

Sorry old term.

Bumping refers to a physical movement of the board causing open circuits or cracking of the traces or opening up of cold solder joints.

There should be an adjustment pot on the linear power supply to bring the voltages higher.

Should there be a 12 volts on that power supply? What is it at?
 
Sorry old term.

Bumping refers to a physical movement of the board causing open circuits or cracking of the traces or opening up of cold solder joints.

There should be an adjustment pot on the linear power supply to bring the voltages higher.

Should there be a 12 volts on that power supply? What is it at?

I don't see an adjustment on the PS or in the manual anywhere so rebuilding may be my only option unless I'm missing something. :( It uses +5, +25 and -25 V to run. The other voltages look fine which is why I was thinking of just running a separate switcher for the +5 as a test to see if that fixes the problem before embarking on a full rebuild.

Bumping huh...new term for me. And that sounds like something that will be a bear to troubleshoot.
 
Can you take a picture of the P.S. Board So I don't have to dig through the shed to see one.
Do you have a Analog voltage meter or scope?

Ah, I had a hard time taking as pic since the board is hard to get to, but I reached around and got a good shot of it...and lo and behold, I see what looks like an adjustment pot! I will try adjusting it and report back, thanks!

Just out of curiosity, what did you have in mind for the analog meter? I may have one stashed around here somewhere but I don't have a scope.
 
Ok adjusting that solved the resetting issue. Wish I had known about that pot before I reflowed those headers and broke the vectors.

So...any tips on where to start on the wonky vectors in the pic above? I can play the game but it just looks funny now. I can post more pics or video later if it will help.
 
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