Black Hole - big capacitors

gibbous

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So I don't think I've ever had a Gottlieb before.

It's in semi-working condition, I get no play sounds. There's a few sounds on boot up. A few coils are out when I go through the coil test. I'll sort those out as I go, but the main thing I noticed is the two large caps in the bottom are way out of spec with what's in the schematics. I mean the voltages aren't lower, but the uFs are way off.

I will replace them with what the schematics indicate, but I was just curious. From my vid experience with monitors I know this sort of thing is bad there, but in this situation, what would these weird caps do to this pin?
 
Way off how? Rated too high and you're likely to overamp components down the circuit, rated too low and it's just like using an underpowered power supply, things either don't work or they are strained by being underpowered and burn themselves out.

Too many variables in components to dictate what the outcome would be, but if the caps are outside of 10% of spec in difference either way, ABSOLUTELY replace them.
 
...but if the caps are outside of 10% of spec in difference either way, ABSOLUTELY replace them.

I would assume you working on a system 80 game. In which case those are just filter caps for the DC voltage. In these particular games C2, which should have a 1.5k resistor across the terminals, supplies 38v to the playfield for the solenoids. That cap can be anything from 4000uf @ 50v as the schematics have up to about 4800uf @ 50v. The other cap C1 is actually a more important cap as it supplies the 12v to the power supply that ultimately gets converted to the 5v for all the logic boards. This cap, which the schematics state should be 6800uf @ 25v, can actually be as high as 12,000uf @ 25v or higher. It is recommended that the cap should be about 10,000uf. The higher the capacitor, the better the filtering of a/c ripple. The bridge rectifier can handle the surge current up to using a 12,000uf cap but, don't go any higher because you don't want to over strain the rectifier. So, if a high rated cap like 10,000uf is installed, then someone already did the "upgrade" and is ok. Although, if you don't know how old the cap is, it's recommended that you replace it anyway. Big daddy is a great supplier of gottlieb repair kits.

http://www.bigdaddy-enterprises.com/repairkits/gottlieb_kits.htm#g-80filters

or

http://www.bigdaddy-enterprises.com/repairkits/gottlieb_kits.htm#g-80ps1 if you need the rectifiers as well.
 
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The larger cap is recommended as mentioned above. In addition early Gottlieb SS games had a number of design flaws related to grounding which need to be corrected to make them reliable. The molex connectors also are problematic and you often need to replace the pins in them. Once these issues are addressed these games are very reliable.

Here is a good repair guide for these games.

http://www.beerorkid.com/pin/Gottlieb Sys80/index1.htm (Part 1)

http://www.beerorkid.com/pin/Gottlieb Sys80/index2.htm (Part 2)
 
haha @idaho. I played a nice working one and got to multiball and it was a dream. Hopefully it's worth the hassle.

C1 says 6800uF, 25V in the schematics, but mine is 10,000uF, 50V. C2 calls for 4400uF, 50V, but is actually 5000uF, 50V.

I will replace them per the numbers you guys have recommended.

Thanks!
 
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