Zemmix too dimmed with RGB-Scart cable

By DarkSchneider

Paladin (716)

DarkSchneider's picture

16-05-2018, 10:59

Using this cable:
http://retrocables.es/tienda/index.php?id_product=242&controller=product&id_lang=4#/activacion-usb
The USB version (5V).

If not connecting the USB simply there is no image. When connecting, there is image but too dimmed. It is supposed that power is only required for auto-switching, not for the image itself. How this can be then?

Then, it depends on the power supplied to the cable, or the reason should be in another place?

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By gdx

Prophet (2156)

gdx's picture

17-05-2018, 01:16

Try with a 100~220μF polarized capacitor on each RGB pin of the scart. (Three same capacitors, the + connected on the wire that go to the RGB21 connector). Try also with a 100 Ω resistor between the pin 8 of RGB21 and the pin 16 of the SCART.

By DarkSchneider

Paladin (716)

DarkSchneider's picture

17-05-2018, 09:42

Not sure how to apply that in the already made cable. Maybe the power connector is used also as amplifier, and because that not connecting it there is no image, and connecting 5V there is dimmed image.

We have the 9V version at hand, will try it. If get more clear image, then probably is because that, and almost sure it would need 12V. But no adapter gives 12V through USB...

By Pencioner

Hero (634)

Pencioner's picture

18-05-2018, 21:47

I think i know possible reason of that issue Smile I have received my Zemmix Neo after the RGB/VGA fix today, thanks to 8bit4ever everything is working fine now. Though, when i connected it via RGB-SCART it was kind of too dimmed. I was disappointed (because i remember it was not dimmed before i sent it to fix, it has different issue but the brightness was ok), but then i started trying everything. My dimmed picture was fixed by (surprise!surprise!) pushing VGA side of cable fully into the connector. It has issue - this white plastic which covers around the slots makes an obstacle when you insert VGA cable. I just lifted that white plastic a very little up and pushed connector so it fits completely. And the picture became bright - with very decent colors too. So, maybe you have the same thing there?

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