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Alan Pope โœ… ๐Ÿบ ๐Ÿง ๐Ÿฑ @popey

Anyone got an ideas how to fix this video horizontal offset? (composite modded) Spectrum+ connected to EasyCap USB capture device.

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@popey Does it do this on a regular TV / monitor?
@popey Does that capture dongle work with other PAL-based devices?

@popey It looks like it's not capturing the horizontal blanking/sync pulses properly. Perhaps the blanking pulse voltage is below the trigger threshold of the capture double but above that of a television. If that's a Sinclair Spectrum, it's pretty old and the voltages could be off due to components shifting out of spec with time.

@popey It would be rather easy to see what's going on if you had an oscilloscope at hand. You might also want to examine the voltage(s) in the power supply of your Sinclair with a multimeter. If a voltage is somewhat low, that could explain why the dongle isn't handling it. I reckon those dongles aren't used with old hardware like that very often. They probably tested it with some camcorders and game consoles and called it a day.

@thor awesome. Thanks. I will mail the guy who did the composite mods and he may know. It has a warranty sticker (done recently) so I don't want to poke about inside yet :)

@popey @thor Ah, that makes sense. What's strange is I have a composite mod on a UK Spectrum that seems to work OK with my NTSC TV. :-l