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Radius pivot color se30 weird random grayscale problem

tact

Well-known member
I've got a very crazy weird issue that is intermittent and kind of hard to explain so I'll try to word it as best I can. I have never been able to figure this out in all these years.

I have a good ol se30 that I recapped many years ago and fully recapped the analog and power supply the voltages are great. It has 68mb of ram, rominator, scsi2sd, diimo50 card and I have a radius pivot color card.

The problem is after a while the radius monitor will flicker and the color becomes slightly discolored until which point I restart or shut it down the next time it starts back up the screen is completely grayscale, the control panel still shows its set to 256bit color but its displaying in grayscale. This issue happens even without the diimo50 rominator and scsi2sd installed with just the radius card by itself. I also have 2 different radius pivot color cards, I have the se30 version And the iisi card modified to fit in the se30. I have tried Both the original v1.0 rom and v2.6 rom so I'm pretty sure its not an issue with either of the radius cards or any of the other ad-ons interfering. This also happens with any different monitor I use either an original apple CRT monitor or a modern LCD.

The only ways I can get it back to color mode are: switch the slot address on the radius card with the jumper settings Or Remove the radius card and boot without it, then the next time I start up with the radius card installed or with a different slot address its back in color, until later on it happens again. This happens randomly anywhere from 10 minutes of running to an hour or two of running and anywhere in between. Sometimes it will be back in color after the macintosh sits there turned off for a very long time. sometimes it doesn't.

The strangest part is this Only happens when the back of the se30 case is on. When the case is off and opened up it never happens. I don't think there is a heat issue but it might be a factor. The fan has good airflow.

Could it be that the case is creating an EMI Shield that might be containing static interference from the monitor or other power parts that might be getting into either the radius pivot cards or the logic board itself? I do have both shields on the analog board and the logic board. What parts or chips on the logic board might even effect this?

This is such a weird issue I'm really looking for you pros who know every little part and exactly how the macintosh se30 logic board works that might have any clue at all or any info that might help me fix this. It's so random and strange and annoying. I don't have another logic board around to swap and see if that even has anything to do with it or it might just be my crazy bad luck with computers and get rare issues that no one else ever has.

If we can't figure this out no big deal I have been dealing with it for years but any information would be greatly appreciated.
Thanks!
 

tact

Well-known member
I may have found some what of a clue to what the culprit might be to this odd problem. Or maybe not but this still needs to be addressed.
While I had my se case off it was sitting in a place on my desk that was rather dark I noticed the tiniest arcing/spark on the flyback transformer, this might be leaking static into the case that might be getting back into the sensitive video parts of the radius card or even logic board that is causing it to glitch out. If you can see it in the pictures , the glue on the flyback has always been a bit burnt but still in good shape not chipped away or anything theres no other damage like cracks or loose wires that i can see. This also seems to go away after it warms up for a few minutes. I doubt this is normal and I should probably look into replacing the flyback, which is actually ironic that I JUST sold my other se on ebay to get some extra cash so I cant swap that analog board to see if it would be better lol . just my luck. I hope I don't have to pay 150$ for a "NOS" part on ebay.
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I also managed to put a couple tiny switches on the radius card where the jumpers for the slot address are, which I had previously removed for clearance because they were sticking up so much they were jammed against the edge of the crt. So now I can easily switch the slot address whenever it goes black and white which strangely fixes it back to color on the next boot I have No idea why this works but it does!. There is Just enough space to get the case back on with these cards in here!

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And if you can see I modified the radius pivot card with a new right angle 120pin eurodin connector so I can slap an asante maccon se30 on top! With the removable daughter board on the rear slot to make space for the video port! Yay!

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tact

Well-known member
I spent the money and got a NOS replacement flyback transformer to replace my good ol sparky stock one, model 157-0042C was replaced with a 157-0026C. After some extensive testing no sparks or arcs I could see and no smell of smoke or anything so I put the case back on and so far there has been no flicker or color issue from my radius card. that may have been the culprit was a burnt out flyback transformer doing who knows what to the radius cards. I will report if the problem ever returns.
The only adjustments I had to turn down the brightness cutoff, this "new" flyback was much brighter than my old one.
oh and the hole for the back pin had to be drilled out just a tiny bit to fit the different model transformer. but it all went well.
Pictures!
=) happy mac once again

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