Weird colours on PAL (demodded) SCPH-1002

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mysfiring
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Weird colours on PAL (demodded) SCPH-1002

Post by mysfiring » November 27th, 2018, 8:06 am

Hi everyone,

I was hoping you might be able to help me diagnose just what's going on here, in terms of video output. The seller described the fault as 'black and white' - but that logo looks like a hue shift more than anything else. According to the seller on eBay, the issue was present with the mod installed, and hasn't changed with the mod removed. Apologies for the potato cam - I couldn't get a direct feed from the console to capture.
IMG_20181127_074759.jpg

Additionally, I found a SMD resistor chilling out (stuck) alongside a 0 ohm link opposite the RCA jacks. From what I could tell on the board, this wasn't displaced by the application of hot air, but stuck there by the pick and place machine, because I can't find anywhere nearby it'd possibly come from. Didn't change the output situation though; removing the resistor didn't change anything.
150 ohm.jpg
Any and all help appreciated! :D

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Shendo
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PlayStation Model: SCPH-9002
Location: Croatia, EU

Re: Weird colours on PAL (demodded) SCPH-1002

Post by Shendo » November 28th, 2018, 1:44 am

Hm... That image looks like it's missing a red channel but the background would be aqua, not white.
Could it be that your phone fixed white balance?

Here is my recreation.
sony logo.png

Is there anything strange around IC501? And do you have an RGB cable to
test the RGB output to see if it's fine?
My PS1 consoles: 2 x SCPH-1002, SCPH-5552, SCPH-7002, 4x SCPH-9002, 2 x SCPH-102.
Dev console: SCPH-9002, MM3 - 7 wire modchip, PAL color mod, CH340 serial cable addon.

mysfiring
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Re: Weird colours on PAL (demodded) SCPH-1002

Post by mysfiring » November 28th, 2018, 9:45 am

Hi Shendo, thanks for your reply.

I just attempted to capture a direct feed from the console itself - while I can view it on the TV just fine, the signal itself is bad enough that the capture card can't lock onto the signal. That said, the colours definitely are presented as captured, with no interference from the white balance of the camera.

Is there a service manual available for the 1000-series? This is a PU-8 board, but there are very few (aside from fuse) part designators on the silk. Looking around other places though, my best guess is that IC501 is a CXA1645M and while it looks like it has previously had things attached to it, when I removed the mod I reflowed each of the pads to ensure none of them had been lifted for a mod.

Here's a picture, if it helps:
IaMG_20181128_093422.jpg
Oh, and no RGB-SCART cable unfortunately.

Thanks!

mysfiring
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Re: Weird colours on PAL (demodded) SCPH-1002

Post by mysfiring » November 28th, 2018, 3:43 pm

So, a quick update:

The seller offered up both a SCPH-1002 and a SCPH-9002 in the same auction. The 9002 was working as intended before I removed its mod, but after doing so started exhibiting the exact same colour issue as the 1002. Turns out that pin 157 on the GPU of the 9002 (unintentional rhyme, sorry!) was lifted, so I added some solder, bent it back down and... No colour shift. SUCCESS!

By that rationale, (and my limited understanding of the situation so far) that should also mean a lifted pin on the 1002 board, but after checking all the packages I can't see anything of the sort. Unless there's been a trace cut during the initial fitout of the mod. But again - nothing that I can see.

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Shendo
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Re: Weird colours on PAL (demodded) SCPH-1002

Post by Shendo » November 29th, 2018, 2:07 am

Oooohhhh I get it now. Someone performed a PAL color mod on the consoles (to get PAL60 in NTSC games).
When you removed mods (modchip, oscillator and bridges) you also removed a bridge which connected that trace to GND.

SCPH-1002 and SCPH-9002 boards differ so for 9002 removing bridge and connecting pin 157 brought it back to original state.
For SCPH-1002 all the magic revolves around IC502, so make sure that there are no cut traces to CXA1645,
look on the both sides of the board.

You can also restore a mod on SCPH-1002 if all else fails. It's not a bad mod,
I too have it on my SCPH-9002 dev system.

It will only affect NTSC games and it will actually bring color on old TVs
where the image would be otherwise black and white.

Edit:
Here is a high res scan of the PU-8 board found in SCPH-1002, so you can check
if something is missing from yours.
My PS1 consoles: 2 x SCPH-1002, SCPH-5552, SCPH-7002, 4x SCPH-9002, 2 x SCPH-102.
Dev console: SCPH-9002, MM3 - 7 wire modchip, PAL color mod, CH340 serial cable addon.

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Re: Weird colours on PAL (demodded) SCPH-1002

Post by mysfiring » November 29th, 2018, 8:00 am

Hi Shendo,

I was figuring as much (at least on the 9002) that this mod had been performed, but when looking at the 1002 I didn't remove an oscillator/xtal; just the mod chip itself. That's (I guess) why there I noticed evidence something had been soldered to the CXA1645 in the past, but was then removed, and when the seller got hold of the unit (and the lack of a mod) observed that it was outputting odd colours.

Thanks for the board scans. I'll check top and bottom of the boards and see how I get along.

Edit:
Hello, what do we have here? I never really thought the idea of a fibreglass pencil for scratching away solder mask would be useful until this console presented itself. Consider me a changed man.
Photo on 29-11-2018 at 10.16 am.jpg

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