VGA-grade Video Cable Connector

VGA-class Video Cable Connector

VGA-class Video Cable Connector

Setting up a new (well, new to me, it’s that old GX270) PC gave me reason to rummage in the Video Cable box and come up with this VGA-class cable. Half the connector shell had worked its way off, giving a nice view of the handiwork. Easily snapped back on with no permanent damage.

The cable works OK at 1280×1024, although the image seems a bit soft, and higher screen resolutions are out of its reach. There are no obvious signal reflections visible on the screen, so the impedance bumps are not as bad as you might think.

The VGA connector includes common returns for the Red, Green, and Blue signals, and the two wires for each color should be twisted together. That obviously hasn’t happened here, but crosstalk doesn’t seem to be much of a problem.

To their credit, they did solder the cable shield to the connector shell, which is a really nice touch. Alas, the impedance of a one-inch pigtail pretty much chokes off the high-frequency stuff you really want to drain to the shell.

Memo to Self: One of these days, run a bandwidth check with the spectrum analyzer. Use 6-dB pads to get nice 75-Ω terminations.

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