big blue "fu" - how can it cause so many problems?

vintagegamer

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big blue "fu" - how can it cause so many problems?

I have ordered a big blue from Bob Roberts for my Tempest. It is apparently at home as of today, waiting for me to do the swap..

I changed the part out in my Asteroids (was working prior to the swap), and to be honest I never really saw any changes. But yet, all over the web (including Bob Roberts' page), the big blue has been deemed responsible for a multitude of graphics glitches in Atari games, dead Atari games completely, and other odd gremlins.

I'm trying to understand the "fu" behind all that is big blue... How can this one part be so responsible for so many varieties of problems? And yes I know it's in the power supply, the "heart" of a game, if you will, but it's just hard to believe it can cause so much widespread disaster.

It would be great to see some changes to my problematic Tempest after I install it but, after not seeing any changes in my Asteroids (then again I don't know what I would have actually seen different), I'm trying not to get my hopes up :(
 
It a big electrolytic filter capacitor that tends to eventually fail, like most anything man made or electronic.
 
I have ordered a big blue from Bob Roberts for my Tempest. It is apparently at home as of today, waiting for me to do the swap..

I changed the part out in my Asteroids (was working prior to the swap), and to be honest I never really saw any changes. But yet, all over the web (including Bob Roberts' page), the big blue has been deemed responsible for a multitude of graphics glitches in Atari games, dead Atari games completely, and other odd gremlins.

I'm trying to understand the "fu" behind all that is big blue... How can this one part be so responsible for so many varieties of problems? And yes I know it's in the power supply, the "heart" of a game, if you will, but it's just hard to believe it can cause so much widespread disaster.

It would be great to see some changes to my problematic Tempest after I install it but, after not seeing any changes in my Asteroids (then again I don't know what I would have actually seen different), I'm trying not to get my hopes up :(

I had graphic issues all of a sudden with my Tempest i changed the Big Blue and now it works great again. I had the same thing with my Asteroids Deluxe and again i changed the Big Blue and it works awesome. My StarWars started to act up about 2 weeks ago changed that Big Blue as well and once again, perfect! I don't get it either but it does fix many issues. I have now changed the Big Blue in all of my Atari games (10 of them) except my Lunar Lander but i plan on doing it as well.

I just wish there was as easy a fix for those freaking Williams Ram errors! LOL
 
Ok, put in the most simplest of layman's terms...

Imagine your Asteroids game how well it would work if you connected it to a light switch, and repeatedly turned it on and off as fast as you can.

Thats the same effect a bad big blue has. Its called a filter capacitor because as the monitor scans, the board processes, the sounds are made, all put various loads on the power supply at any given time, even down to the microsecond. Without a "filter" to smooth out all the little spikes, the positive power supply would be very "noisy" and cause all sorts of issues. While your meter may show +5v at the board "on average", it may really be 4v at the very instant you press FIRE.

Another analogy - think of a car battery in a car. In addition to starting said car, it acts like a filter capacitor for your car, so when you press the brakes, put on a turn signal, fire up the AC, or crank up your gangsta rap, your headlights don't shut off and your fuel injection doesn't get starved of the voltage it needs.

Capishe?
 
These capacitors can have internal problems that are intermittent and/or only show up under a full load. They might even be below their stated capacity after all these years.
 
I had graphic issues all of a sudden with my Tempest i changed the Big Blue and now it works great again. I had the same thing with my Asteroids Deluxe and again i changed the Big Blue and it works awesome. My StarWars started to act up about 2 weeks ago changed that Big Blue as well and once again, perfect! I don't get it either but it does fix many issues. I have now changed the Big Blue in all of my Atari games (10 of them) except my Lunar Lander but i plan on doing it as well.

I just wish there was as easy a fix for those freaking Williams Ram errors! LOL

That is definitely inspiring news, Braido... thanks for sharing!
 
Maybe I am lucky but I've been through about 40+ video games since I started collecting and I have YET to come across a problem that was fixed with a Big Blue. I've replaced at least 4 or 5 of them, and each time they've done nothing to rectify the problem(s) I was having.
 
Maybe I am lucky but I've been through about 40+ video games since I started collecting and I have YET to come across a problem that was fixed with a Big Blue. I've replaced at least 4 or 5 of them, and each time they've done nothing to rectify the problem(s) I was having.

And we have our first antagonist. :D
 
Ok, put in the most simplest of layman's terms...

Imagine your Asteroids game how well it would work if you connected it to a light switch, and repeatedly turned it on and off as fast as you can.

Thats the same effect a bad big blue has. Its called a filter capacitor because as the monitor scans, the board processes, the sounds are made, all put various loads on the power supply at any given time, even down to the microsecond. Without a "filter" to smooth out all the little spikes, the positive power supply would be very "noisy" and cause all sorts of issues. While your meter may show +5v at the board "on average", it may really be 4v at the very instant you press FIRE.

Another analogy - think of a car battery in a car. In addition to starting said car, it acts like a filter capacitor for your car, so when you press the brakes, put on a turn signal, fire up the AC, or crank up your gangsta rap, your headlights don't shut off and your fuel injection doesn't get starved of the voltage it needs.

Capishe?


Si, io capisco... :D and how did you know I liked Gangsta Rap? /sarchasm
 
I would not bank on changing it to be a magic fix. Out of maybe 20 Atari games it was only an issue in 1 for me. In that case the initial failure most likely caused multiple other failures like fried ram and fried monitor parts etc.. Probably a cascade of failure.
Look at the most obvious and cheapest solutions first which would be new solder on the interconnect on the main and aux pcbs being number 1 to fix then any obvious monitor problems.

And we have our first antagonist. :D
 
Look at the most obvious and cheapest solutions first which would be new solder on the interconnect on the main and aux pcbs being number 1 to fix then any obvious monitor problems.

Those I have actually done already, and the problems persist with a set of boards that I did reflow, as well as with a set which I did not reflow. It's an interesting comedy of errors so I'm hoping big blue will come thrue (spelling error done on purpose)!
 
And we have our first antagonist. :D

Allow me to pile on :)

I have replaced the big blue in all my Atari (and Midway) games, yet I've never replaced it to solve a problem. There's no clear answer on how long they last, so after 25-30 years, I do it as a best practice because I understand the principles orion3311 mentioned above. The chips on game boards are quite sensitive to bad power, so it can only do good for your game to make sure you have good power.
 
Maybe I am lucky but I've been through about 40+ video games since I started collecting and I have YET to come across a problem that was fixed with a Big Blue. I've replaced at least 4 or 5 of them, and each time they've done nothing to rectify the problem(s) I was having.

+1

If you put a good DVM in AC set-up and measure across the Big Blue terminals and have less then about 0.4V, the BB is still fine.

The really funny thing is that this is about the biggest cap in the hobby, yet, when you order a cap-kit, they almost always omit the really large caps because "they usually don't go bad"....mmmmmmmm
 
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