Blanking & blanking ground - 150ohm resistors?

Started by Stilton, January 07, 2007, 09:00:11 AM

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Stilton

I got a PVM 2030 some time ago and have been hacking all of my SCART RGB cables to work with it. My DIN8 SMS/MD cable gave a horrible picture due to composite video connected to what should be sync. That was an easy fix.  

Unfortunately, it wasn't a complete fix, as I noticed the colors were very dark. I opened up the SCART end and noticed a 150 ohm resistor right on pin 18 - blanking ground.

When I removed the resistor, I got a beautiful level of brightness, but solid blocks of color were displayed very oddly. They would form a gradient from correct color on the left all the way to black on the right (depending on the size of the block), with increasing darkness in between.

I tried a 10 ohm, then a 15 ohm resistor, and noticed nothing and overall darkness, respectively.

I suspect there is a simple solution, but I am a simpleton and can't find the answer by Google. Can anyone help?

(By the way - the monitor is a beaut and works great with all of the other RGB cables I've tried)

viletim!

This resistor and the 'fast blanking' pin are a peculiarities of the SCART connector. It has nothing to do with video brightness/contrast - It's purpose is to put a TV into RGB mode.

Take a look here for a diagram of what should be inside a Mega Drive RGB cable.

Stilton