vga cable anatomy......

so i am making a VGA cable for the PSOne lcd mod, and running into some things that im not sure are proper for a vga cable...

i used a multimeter to determin which cable go to which pins, and wrote this down.

i need to have 3 pins (RGB grounds) all tied to one solder point on the lcd, which is no big deal.

So when i open the cable, the first thing i see is a metal "mesh" similar to the sleeving material or chinese finger trap pattern. I test continuity of this, and it seems to be ground (well to the pins that i want.

There is also foil directly under this.....why? is this normal? why foil?



so after i solder everything and i test conitnuity, i find that the ground metal mesh, is connected to the metal face of the pins at the connector.....is this faulty?

It's not faulty.
The mesh and foil provide a sheilding from external radio interferance. It is normally connected to frame ground, which is the frame of your case, and the "D" shaped shroud arround most cable connectors.
Electrically, frame ground and signal ground are the same when checked with a meter.

okay, but when i test the signal ground (from bare wire) to the frame at the plug, should there be continuity?

Yes, I think so.

The PC has one ground and VGA is an unbalanced signal. So chassis frame ground is the same as electrical ground (theoretically).

If this were a microphone or other signal coming off a balanced line, then chassis ground is not connected to any of the pins, but the frame/outer connection (electrically separate). VGA signal return and chassis ground are the same point, electrically that is.

sdwood actually answered the question before me.

"Electrically, frame ground and signal ground are the same when checked with a meter".

That means there should be continuity.

okay i think i get it.....this weekend will attemp to remake the cable

It is like this with LPT cables too. If you open up any quality cable, there will be that metal wrapping inside for grounding.

yeah there was that, and now i look and i see that there are more wrappings around the R G and B wires...

at first i was like....these would short eachother and that wouldnt work....so i didnt use them. Then i realized that they all connect to teh same pin on the PSon anyways...

but when i check the contiunity, the outermost sleeving is connected to the pins of the plug that i need....so that threw me off...