Atari Power supply rebuilding...

[RayB]

In the past, I've replaced Big Blue in a couple Atari power supplies, and if warranted, some fuse holders. Now, I see Bob sells a kit that also replaces the bridge rectifier. How reliable are bridge rectifiers? I'm just wondering if it's at all necessary to replace a perfectly good original for reliability? (Caps tend to age; so what about diodes?)

[sarge]

Diodes have no tendency to break down with age.  Usually the only thing that will kill a diode is exceeding its current rating.  Electrolytic capacitors only die with age because the electrolyte dries up in them with heat and time. 

[Level42]

I agree. Not needed. Think about how long LED's live......those are diodes too !

[ChadTower]

I don't entirely agree.  I have seen an awful lot of hard to diagnose issues in pinball machines go away by replacing the BRs.  I suspect a lot of failures would be prevented if we got to the bridge before it failed on us.

[Level42]

I have seen an awful lot of hard to diagnose issues in pinball machines go away by replacing the BRs.

I that your own experiences or from reading pinball threads ?

[ChadTower]

I that your own experiences or from reading pinball threads ?

Some of both.  Threads have been mostly consistent with what I've seen myself.  It's cheap to do, right?  Your power supply is the most important part of the game in terms of reliability.

[Ken Layton]

In the Atari power brick, the bridge rectifier is really heat-sinked pretty well and dissipates the heat well. I've seen far fewer bridge rectifier failures in Atari power bricks than in a pinball machine.

In pinball machines (Williams in particular) the bridge rectifiers are NOT heat-sinked well at all. Seems like they get too hot and fail from heat. I've lost count of how many bridge rectifiers I've replaced in Williams/Data East/Sega pinballs over the years, but it's over the 100 mark for sure.

You know how many bridge rectifiers I've replaced in Atari power bricks over the past 25 years? Only SIX!

[Neverending Project]

You know how many bridge rectifiers I've replaced in Atari power bricks over the past 25 years? Only SIX!

What's impressive is that you remember the exact number... did you name them? 

[Level42]

Thanks Ken, as always the best info around !

So, the conclusion is that diode's (BR's) don't go unless you torture them I guess the BR's also have a much higher load on pinballs than on videogames.

Ken, did those 6 have any "follow-up" damage from the BR going bad ? I guess the fuses will go very quickly when one of the diode's in a BR goes bad ?

[Ken Layton]

Burnt quick connect terminals on the bridge rectifier when the rectifier went bad.

[mwade109]

Hey, I am about to rebuild two Atari Brick power supplies to sell (need to clear out some of the bulky stuff) and came across something perplexing. I believe they both came out of original Centipede machines but one of the power supplies has the bridge rectifier as usual and the other has no marking of it ever being there, there is usually a square mark or something on the chassis or discolored and no unhooked wires.  Have you ever seen this? Was this one maybe NOT from a Centipede?
Thanks
-mike

In the Atari power brick, the bridge rectifier is really heat-sinked pretty well and dissipates the heat well. I've seen far fewer bridge rectifier failures in Atari power bricks than in a pinball machine.

In pinball machines (Williams in particular) the bridge rectifiers are NOT heat-sinked well at all. Seems like they get too hot and fail from heat. I've lost count of how many bridge rectifiers I've replaced in Williams/Data East/Sega pinballs over the years, but it's over the 100 mark for sure.

You know how many bridge rectifiers I've replaced in Atari power bricks over the past 25 years? Only SIX!

[Ken Layton]

You have seperate diodes on a little circuit board attached to "Big Blue". So I would say that brick is likely out of some other game than a Centipede.

[jennifer]

It diddnt come up on my list, I would wonder if it isn't out of a older B/W something, It kinda has the look,  possibly international?