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--- blog:zx_fault1 [2020/08/10 22:01] – [Testing] john
+++ blog:zx_fault1 [2020/08/11 17:55] (current) – [Argh! More Crashing!!!] john
@@ Line 49: / Line 49: @@
 ===== Third Attempt - RAM Chip Replacement =====
+**[Update - August 10th 2020]**
 Okay, so fixing any suspect solder joints didn't do it, neither did replacing all of the capacitors. The only thing left is to begin replacing the various chips. The most likely is memory, followed by the Z80 and the ULA.
@@ Line 73: / Line 75: @@
 ==== Testing ====
+**[Update - August 10th 2020]**
 So, did it work?
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 I also noticed that the picture was substantially clearer than it had been in the past. I'm not sure which areas on the board are served by the capacitors that were replaced, but if they have any involvement in the video out circuitry I wouldn't be surprised, the image quality over the RGB scart connection into my OSSC is by far the best I've ever seen a ZX Spectrum produce. It it //outstanding//.
-{{:blog:img_1743.jpg?400|}} {{:blog:img_1744.jpg?400|}}
+{{:blog:img_1743.jpg?600|}} - OSSC Line5x mode at 1920x1200, no scanlines
+{{:blog:img_1744.jpg?600|}} - OSSC Line5x mode at 1920x1200, 12% scanlines (subtractive)
+And close up images of the individual pixels on the screen:
 {{:blog:img_1745.jpg?400|}} {{:blog:img_1746.jpg?400|}}
+//Now that's a result!//
+====== Argh! More Crashing!!! ======
+Whilst the Spectrum seems to be stable running by itself, I have found that plugging anything in to the edge connector (my DivIDE+ CF adapter, or my Penguin PS/2 keyboard interface from Lotharek.pl), the screen corruption and crashing returns instantly.
+Oh, and now it's back to screen corruption all the time m(
+{{:blog:img_1747.jpg?400|}}
+**[Update - August 11th 2020]** - And now it stops doing it without anything plugged in ... It seems as if once you've plugged a peripheral in, the system will keep powering on to screen corruption like this, until you've let it sit unpowered, without any peripherals, for an extended period of time. Then it's fine (without peripherals) again.
+Have ordered a replacement power regulator (Traco TSR 2-2450 - switching regulator in place of the LM78S05 linear regulator) and Z80 CPU, as they are the next suspects. Especially when it appears to be far more stable without anything plugged in to the expansion bus.