Display issue with new cable extensions

[LabAnimal]

I've just received some VGA cable extensions so that i can move my monitors to better positions further away from my case...

Had a horrible ordeal with PC Mall getting the damn things in the first place -but this is another story for another thread...

Now that i've hooked up the cables (rather quickly) and moved the monitors around, The image quality has degraded - looks like the its ghosting somewhat!

Is this due to cheap cables (yes they were rather at R25 a shot) as i doubt they are shielded well, and even if so, is there a way to clear this up.

I was thinking of bundling them together to run alongside each VGA able to Each monitor, away from other cables like Power cables...

Any suggestions?

 

[slayerza]

I suspect that some signal interference might be at play and your idea of keeping the cables clear of the power cables might show some improvement. However I suspect this is more to do with the longer propagation time down the cable than with signal interference. If the latter is the case more expensive cables could be the answer as these cables have better connectors, are better shielded and generally make use of better materials.

 

[arf9999]

I agree with slayer, while shielding may be an issue, it is more likely that you're getting cable reflection from poor transmission.

To solve the shielding issue, try wrapping them in tinfoil (make sure that you earth it). Seems stupid, but it does work.

 

[LabAnimal]

earth the tinfoil ? perhaps place an earth strap onto the chassis of the pc case?

I've isolated the cables from the power cables, however i cable tied the two vga cables together to run together - now i have these bars from top to bottom with heavy ghosting and slight flicker.... bloody irritating!.

 

[Asha'man X]

I have this same issue at work. We have a number of data projectors in classes that run to video splitters so that monitor and projector can be on at once. Some rooms have no issue, it's prefectly clear. Other rooms have this ghosting like effect, and I know it's not the monitor, but the VGA cable from the PC to the splitter causing it. Only thing I can think of that is a common factor.

 

[nocilah]

I've just received some VGA cable extensions so that i can move my monitors to better positions further away from my case...

Had a horrible ordeal with PC Mall getting the damn things in the first place -but this is another story for another thread...

Now that i've hooked up the cables (rather quickly) and moved the monitors around, The image quality has degraded - looks like the its ghosting somewhat!

Is this due to cheap cables (yes they were rather at R25 a shot) as i doubt they are shielded well, and even if so, is there a way to clear this up.

I was thinking of bundling them together to run alongside each VGA able to Each monitor, away from other cables like Power cables...

Any suggestions?

ensure you are using the THICK cables when doing extensions. Last time i did an extension made from the thinner variety of cable I had severe ghosting. The moment i used the more expensive cable all was clear as crystal.

 

[slayerza]

The ghosting stems from improper termination / impedance of the cable used to perform the extension. This will lead to reflections of the signal causing interference within the cable and not from outside sources. As this affects each signal line differently ghosting occurs.

The foil trick might work, although I suspect the cheap cables are to blame. Just compare the cables of a KVM switch to the cheap extension cables to see the difference in quality

 

[LabAnimal]

thanks for all the feedback - going to try the foil thing and report back how it works.

The foil thing will be a short term solution - will definitely head out to buy better cable!

 

[Arthur]

Remember that VGA is analogue, so cable lengths are inherently more limited. Original VGA spec allowed for max total cable length of 3m, though most modern array hw output drivers (not the sw) will push signal adequate for double that.

So the above advice is good: get extension cables with quality D-connectors, thicker signal strands, and good shielding. Make sure all connectors are properly screwed in and grounded.

 

[LabAnimal]

To report back - the foil was a waste of time, not to mention a pain to @$$. Between the cat and my limited patience... it was a blast! I now have two sets of cable tied tinfoiled sci-fi vga cables that still does the same thing... blurrrrr and ghost....

oh well - am going to start looking for that better thicker cable etc...

One last question - is it better to buy the molded ones, or just to go buy the cable and plugs yourself and make it myself? (yea i can make my own cables, just figured its less of a pain if i buy them ready made...)