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A great how-to on converting a VGA to RJ45. From the site, “I was just about to finish my projector project when I hit a snag. I needed a super long VGA cable to reach from the LCD my computer, which were on opposite sides of the room. Initially I was going to move my computer to the projector but decided against it. I read a few articles involved with VGA conversion and decided to give it a shot. Of course it might have been more practical to buy an extra long VGA cord for around $25 plus shipping, albeit more expensive.” Thanks jher! Link.
HOW TO – VGA to RJ45 Conversion
Posted by nataliezdrieu | Friday February 3rd, 2006 3:42 PM
Categories: Electronics | 3 Comments
I’ve made a setup like this a while back, and noticed
the screen (TFT) went black for a second when lights
were activated elsewhere in te house.
A solution for this problem…
Still need to dig deeper.
I suppose you could, but why?
The characterisitic impedance of RJ45 is 100 Ohms.
So the single-end impedance to the wire you are using as the return wire is about 50 Ohms (give or take.)
VGA uses coax which has 75 Ohms single-end impedance to the return wire. So using this as a cheap cable extension is not really what you want to do since the circuitry driving VGA ia expecting a 75 Ohm transmission line terminated to 75 Ohms at the receiver end. Also Coax is sheilded much better than the twisted pair covered by foil in RJ45. The VGA cable is not so much more expensive enough to make this worth it.
I suppose you could, but why?
The characterisitic impedance of RJ45 is 100 Ohms.
So the single-end impedance to the wire you are using as the return wire is about 50 Ohms (give or take.)
VGA uses coax which has 75 Ohms single-end impedance to the return wire. So using this as a cheap cable extension is not really what you want to do since the circuitry driving VGA ia expecting a 75 Ohm transmission line terminated to 75 Ohms at the receiver end. Also Coax is sheilded much better than the twisted pair covered by foil in RJ45. The VGA cable is not so much more expensive enough to make this worth it.
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