Picasso IV color issues

brett71 · 08 October 2020, 23:19

I've got a nice Picasso IV video card that I'm having some issues with. When I first came into possession of the card, it worked fine most of time, but occasionally the colors would go significantly bluish. It was a lot like the red or green, not sure which it would be, just cuts out. Over time, the video signal would go blue more and more often until it became the predominant condition. Wiggling the cable or putting additional pressure on the VGA connector would influence this and temporarily restore the colors as long as I was holding the cable or connector in place. I tried different VGA cables to see if that was the issue, but was not. I sent the card to Acill who thought it was a defective/worn out VGA connector and he replaced it for me, but when I got the card back, the problem is persisting, and seems even more intermittent. I don't have any complaints about Acill's work or anything like that, I think the problem might just run deeper. I've posted a video to illustrate the card's current state.

[ Show youtube player ]

A secondary issue which cropped up once I got the card back appears to be with the scandoubler. When I first installed it I had the 3000 set to a native NTSC Hi-Res Laced mode. When I initially booted the machine, the video output was blue, garbled, and rolling on my VGA monitor. I moved the cable to the 3000's built-in scandoubler and the output was perfect. From there, I changed the screenmode to a Picasso IV 1280x1024 8-bit screenmode and moved the cable. The output was at the correct resolution, but blue. Next, I changed the screenmode back to NTSC Hi-Res Laced and when I clicked "Use", I got no output, just a black screen. After waiting a minute or two, I then got output similar to the initial output (blue, garbled, rolling), but after a few seconds, the picture cleared up to how it should appear, stopped rolling, but remained blue.

I'm just wondering if anyone has any thoughts on where the faults could be?
Acill told me that he did test the board after the VGA connector fix and did not see these issues. Could I have a daughterboard/video slot problem in my 3000? I do have another Amiga 3000 that I can swap out the daughterboard or move the card to and see if the problem persists and follows the card or not. Is there another component on the card which might need to be fixed/replaced? Would it be advisable to send the card back to Acill and have it re-capped?

Damion · 09 October 2020, 06:07

The fact that flexing around the connector area temporarily solved the problem would seem to indicate that a contact issue somewhere is still likely, which bodes well for a fix. Have you carefully tried poking around other areas to attempt narrowing down the location?

Have all slots and contacts been cleaned, chips on the PIV removed and cleaned, or at least re-seated? (Don't attempt the latter without great care; those sockets are fragile!)

Regarding the PIV's capacitors: I tested some years back with an ESR meter (older 1.2 board), and most of them had failed. I replaced them, though the card still exhibited wonky scandoubler output for the first few minutes when cold...

Daedalus · 09 October 2020, 10:38

That does look like a loss of the red signal. Are you sure there's nothing close by the board that could be touching the contacts? There look to be ceramic capacitors near the VGA port - these can fail occasionally too, could result in a short to ground that is resolved by slightly flexing the board. I've seen similar issues on the A600 and A1200, where ceramic capacitors fail and take out a signal.

brett71 · 09 October 2020, 16:29

I've posted another video which illustrates not only the loss of red signal, but also the issues with the scandoubler. The screenmode in effect is a native NTSC Hi-Res Laced mode.

[ Show youtube player ]

I left the 3000 cover off while I took this video, and I can confirm that if I place my finger on the edge of the card and flex the card slightly, it does have a direct effect on both issues, either for better or for worse.

At this point, I'm not sure what can be done, but it does appear like the card has undergone significant flexing, but no idea the extent of the damage or if it can be repaired. As was mentioned earlier, the cause could also be components which are failing and intermittently grounding as well.

Thoughts?

Daedalus · 09 October 2020, 17:54

Hmmm, ceramic capacitors really don't like being flexed, and can develop hairline fractures invisible to the naked eye. But that said, it could easily be some other fractured solder joints on the card, or an issue with the video slot connector on the backplane - at least for the scandoubler issue.

brett71 · 09 October 2020, 19:16

I've transferred the card to another 3000 and the problems are persisting. Looks like the faults are on the Picasso.

Can this be repaired?

I took a closer look at the card and also saw something on the backside of the card which appears to be a repair to a trace which leads to the ceramic capacitors behind the VGA port. This could be part of the issue with the red signal cutting out, but not sure about the scandoubler issues.

DarrenHD · 09 October 2020, 20:37

Quote:

Originally Posted by brett71

I've transferred the card to another 3000 and the problems are persisting. Looks like the faults are on the Picasso.

Can this be repaired?

I took a closer look at the card and also saw something on the backside of the card which appears to be a repair to a trace which leads to the ceramic capacitors behind the VGA port. This could be part of the issue with the red signal cutting out, but not sure about the scandoubler issues.

You may want to post on a1k.org in the international section. There is alot of expertise there on the Picasso IV.
From what I can tell those traces in your photo still loook OK, but I am not an expert.

Daedalus · 09 October 2020, 21:47

The only way to be sure would be to get a multimeter at it, but if there's a crack under there, it's entirely possible that it's opening up again when the board flexes. Definitely worth investigating anyway. Do you have a multimeter?

brett71 · 09 October 2020, 22:02

Quote:

Originally Posted by Daedalus

The only way to be sure would be to get a multimeter at it, but if there's a crack under there, it's entirely possible that it's opening up again when the board flexes. Definitely worth investigating anyway. Do you have a multimeter?

I do not and really don't have any experience or knowledge working with electronics at the component level.

08 October 2020, 23:19	#1
brett71 Registered User Join Date: May 2010 Location: Ames, IA, USA Posts: 521	Picasso IV color issues I've got a nice Picasso IV video card that I'm having some issues with. When I first came into possession of the card, it worked fine most of time, but occasionally the colors would go significantly bluish. It was a lot like the red or green, not sure which it would be, just cuts out. Over time, the video signal would go blue more and more often until it became the predominant condition. Wiggling the cable or putting additional pressure on the VGA connector would influence this and temporarily restore the colors as long as I was holding the cable or connector in place. I tried different VGA cables to see if that was the issue, but was not. I sent the card to Acill who thought it was a defective/worn out VGA connector and he replaced it for me, but when I got the card back, the problem is persisting, and seems even more intermittent. I don't have any complaints about Acill's work or anything like that, I think the problem might just run deeper. I've posted a video to illustrate the card's current state. [ Show youtube player ] A secondary issue which cropped up once I got the card back appears to be with the scandoubler. When I first installed it I had the 3000 set to a native NTSC Hi-Res Laced mode. When I initially booted the machine, the video output was blue, garbled, and rolling on my VGA monitor. I moved the cable to the 3000's built-in scandoubler and the output was perfect. From there, I changed the screenmode to a Picasso IV 1280x1024 8-bit screenmode and moved the cable. The output was at the correct resolution, but blue. Next, I changed the screenmode back to NTSC Hi-Res Laced and when I clicked "Use", I got no output, just a black screen. After waiting a minute or two, I then got output similar to the initial output (blue, garbled, rolling), but after a few seconds, the picture cleared up to how it should appear, stopped rolling, but remained blue. I'm just wondering if anyone has any thoughts on where the faults could be? Acill told me that he did test the board after the VGA connector fix and did not see these issues. Could I have a daughterboard/video slot problem in my 3000? I do have another Amiga 3000 that I can swap out the daughterboard or move the card to and see if the problem persists and follows the card or not. Is there another component on the card which might need to be fixed/replaced? Would it be advisable to send the card back to Acill and have it re-capped?

09 October 2020, 19:16	#6
brett71 Registered User Join Date: May 2010 Location: Ames, IA, USA Posts: 521	I've transferred the card to another 3000 and the problems are persisting. Looks like the faults are on the Picasso. Can this be repaired? I took a closer look at the card and also saw something on the backside of the card which appears to be a repair to a trace which leads to the ceramic capacitors behind the VGA port. This could be part of the issue with the red signal cutting out, but not sure about the scandoubler issues. Attached Thumbnails

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09 October 2020, 06:07	#2
Damion Registered User Join Date: Mar 2008 Location: US Posts: 315	The fact that flexing around the connector area temporarily solved the problem would seem to indicate that a contact issue somewhere is still likely, which bodes well for a fix. Have you carefully tried poking around other areas to attempt narrowing down the location? Have all slots and contacts been cleaned, chips on the PIV removed and cleaned, or at least re-seated? (Don't attempt the latter without great care; those sockets are fragile!) Regarding the PIV's capacitors: I tested some years back with an ESR meter (older 1.2 board), and most of them had failed. I replaced them, though the card still exhibited wonky scandoubler output for the first few minutes when cold...

09 October 2020, 10:38	#3
Daedalus Registered User Join Date: Jun 2009 Location: Dublin, then Glasgow Posts: 6,334	That does look like a loss of the red signal. Are you sure there's nothing close by the board that could be touching the contacts? There look to be ceramic capacitors near the VGA port - these can fail occasionally too, could result in a short to ground that is resolved by slightly flexing the board. I've seen similar issues on the A600 and A1200, where ceramic capacitors fail and take out a signal.

09 October 2020, 16:29	#4
brett71 Registered User Join Date: May 2010 Location: Ames, IA, USA Posts: 521	I've posted another video which illustrates not only the loss of red signal, but also the issues with the scandoubler. The screenmode in effect is a native NTSC Hi-Res Laced mode. [ Show youtube player ] I left the 3000 cover off while I took this video, and I can confirm that if I place my finger on the edge of the card and flex the card slightly, it does have a direct effect on both issues, either for better or for worse. At this point, I'm not sure what can be done, but it does appear like the card has undergone significant flexing, but no idea the extent of the damage or if it can be repaired. As was mentioned earlier, the cause could also be components which are failing and intermittently grounding as well. Thoughts?

09 October 2020, 17:54	#5
Daedalus Registered User Join Date: Jun 2009 Location: Dublin, then Glasgow Posts: 6,334	Hmmm, ceramic capacitors really don't like being flexed, and can develop hairline fractures invisible to the naked eye. But that said, it could easily be some other fractured solder joints on the card, or an issue with the video slot connector on the backplane - at least for the scandoubler issue.

09 October 2020, 21:47	#8
Daedalus Registered User Join Date: Jun 2009 Location: Dublin, then Glasgow Posts: 6,334	The only way to be sure would be to get a multimeter at it, but if there's a crack under there, it's entirely possible that it's opening up again when the board flexes. Definitely worth investigating anyway. Do you have a multimeter?

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