Author Topic: 6128 Video issue  (Read 1727 times)

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Offline Vapid

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6128 Video issue
« on: 23:46, 13 November 15 »
I've just got a 6128, and I'm having some video issues, I have the RGB Scart/power adapters here. Amstrad CPC 6128 TV Connection Kit


The picture show fine, but every now and then will have a weird flicker. here's a YouTube video of it, happens around 5 and 10 seconds in. CPC 6128 Video problem. - YouTube

Anybody have any experience here with this problem or have a solution on how to fix it, I would appreciate any help anybody can give me. Thanks.

Online Bryce

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Re: 6128 Video issue
« Reply #1 on: 00:03, 14 November 15 »
There can be two causes for this. The first is that the SCART doesn't know for sure where the signal is coming from and flicks to Composite every so often. This can be cured by adding a battery or capacitor to properly set the RGB selector input. The second cause is that the processor in the TV is using a sample rate that isn't able to properly sync with the CPCs Sync signal. This isn't easily solvable unfortunately. Converting the signal to S-Video via an AD724 can solve it, as the AD724 is more "forgiving" and has a perfectly clocked PAL sync output. This is what my S-Video adapter does.

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Offline Vapid

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Re: 6128 Video issue
« Reply #2 on: 00:31, 14 November 15 »

Adding a capacitor sounds like the easiest option, even if my soldering skills are terrible!
Is there any guides about, on which capacitor is needed/where to solder it?
I tried also running the RGB cable through my "SLG in a box" connecting to the same TV via VGA and also my pc monitor, which instead of the odd flickering every now and then, made it screen constantly "shake" instead, at least that's the best way I can describe it.

Online Bryce

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Re: 6128 Video issue
« Reply #3 on: 00:46, 14 November 15 »
Try wiring the cable like this: TV SCART cable - CPCWiki

Bryce.

Offline Vapid

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Re: 6128 Video issue
« Reply #4 on: 03:02, 14 November 15 »
Well i had a try at rewiring the cable and it didn't got to great, prob due to my lack of soldering skills/lack of expertise, ive got the cable back to how it originally was now atleast, may buy the parts try making one from scratch rather than changing the RGB one i already have.

Offline CraigsBar

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Re: 6128 Video issue
« Reply #5 on: 13:59, 14 November 15 »
I have a TV that exhibits that exact same problem. I just use a different telly.
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