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My very first VGA cable

R

Rene

Jan 1, 1970
0
I recently created a small 6" VGA cable for a little computer system that I
am creating:



http://home.comcast.net/~rene413/CC.JPG



A couple of days ago, I asked a question regarding the creation of a VGA
cable and there where some post pointing out some draw back that I may have
due to not using a coax cable.



Could someone tell me what are the drawbacks about using just plain soldered
cables like I did? Aren't regular monitor cable created this way? Is there
something I can do to improve on my cable quality?



Thank you.
 
J

John Larkin

Jan 1, 1970
0
I recently created a small 6" VGA cable for a little computer system that I
am creating:



http://home.comcast.net/~rene413/CC.JPG



A couple of days ago, I asked a question regarding the creation of a VGA
cable and there where some post pointing out some draw back that I may have
due to not using a coax cable.



Could someone tell me what are the drawbacks about using just plain soldered
cables like I did? Aren't regular monitor cable created this way? Is there
something I can do to improve on my cable quality?



Thank you.

At 6", most anything will work. For longer runs, the RGB signals
should be shielded and impedance matched, namely coax. Just wires in a
ling cable run will look ugly on a computer monitor, but may be OK for
a TV-resolution display.

John
 
S

soundman

Jan 1, 1970
0
Rene said:
I recently created a small 6" VGA cable for a little computer system that I
am creating:



http://home.comcast.net/~rene413/CC.JPG



A couple of days ago, I asked a question regarding the creation of a VGA
cable and there where some post pointing out some draw back that I may have
due to not using a coax cable.



Could someone tell me what are the drawbacks about using just plain soldered
cables like I did? Aren't regular monitor cable created this way? Is there
something I can do to improve on my cable quality?



Thank you.

75 ohm balanced cable is the right stuff to use - normally a coax but it can
be a twisted pair as well. But the problem with not using it only appears
when the cable run starts getting longer than a few feet. The problem will
appear normally as a ghost image to the right of the real image on the
screen. It is caused by the signal reflecting from the end of the cable, to
the beginning and back to the end so it appears as a faint image a little
later than the first image. Using 75R cable will usually stop the effect
appearing. However, there are some VGA outputs that don't drive the cable
properly, so even with the right cable, the problem is still evident if the
cable length is extended past 10 feet or so. I come across this problem
from time to time but much less now than in the past. It seems that fewer
manufacturers are cheating with their output drivers than before.

Your cable length will have none of these problem, but if you aren't happy
with the quality, you may find there is a problem with either the VGA output
or the display itself. It won't be your cable as log as the soldered joints
are good
 
R

Rich Grise

Jan 1, 1970
0
soundman said:
that

75 ohm balanced cable is the right stuff to use - normally a coax but it can
be a twisted pair as well.

No, the video is single-ended. A twisted pair will work, and just ordinary
wires will work, and seeing the little link in the little link ( ;-) ), it
certainly wouldn't be worth it to strip, tin, and solder six ends of 3/16"
coax. Been there, done that. :)

Until I saw the pic, I thought '6"' was a typo. :)

But Rene, you're the one on the ground - how _does_ it work?

Cheers!
Rich
 
R

Rene

Jan 1, 1970
0
But Rene, you're the one on the ground - how _does_ it work?

The cable actually works pretty good, the final cable length will be only 3"
(half the size of what I have right now) so I expect to not have any
problems there either.



The reason why I posted this was mainly to see if I was missing something or
simply to get general feedback.



Thank you.
 
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