How to prevent VGA cable to cause interference?

[Marsupial]

I figure this is the best place to ask...

I have recently acquired a 19inch CRT monitor (samsung) that has amazing colors.

When I use the cable that came with it (no idea if its the OEM cable from samsung or some dollar store the previous owner had; got it used from a computer store)

the image is blurry. Not really blurry, but kinda shadowy. There is like a ghost image that forms to the right of the image, maybe 5 pixels away. Its visible mainly if you look at text and precise things like that.

If I change the cable for a new one; the image is crystal clear.

Short of throwing away that cable and getting a replacement, is there something that is doable?
Maybe looping trough ferrite?
I never experiences anything like that before...

altough getting ferrite might be as expansive as changing the cable altogether. lol. but for knowledge sake...

[MonMotha]

Is this an arcade monitor or a PC monitor?

If it's a PC monitor, you want a cable with real 75ohm impedance lines inside (ideally mini-coax).  The 75ohm termination inside the monitor will then keep all that ghosting and such to a minimum.  A ferrite won't help much with this, and you're right, it'll probably cost you almost as much to get one as a reasonably decent cable.  Just get a decent cable.  You can try just coiling up the cable a few turns.  That will at least tend to keep things off the outer shield (if it even has one).

I have some really nice CRT monitors that I can run at 1920x1200@96Hz (no, I'm not kidding).  The bandwidth of that signal easily tops 1GHz if you want sharp edges.  I've had to try several cables before finding one that works well before   Heck, I have trouble finding video cards with DACs that can keep up, these days.

[Marsupial]

it is a pc monitor, an SyncMaster 950p by Samsung.

I am impressed, your trick of coiling the cable does help quite a lot, the ghosting is still present, but really not as visible.

This said, I'll use another cable.  would this "bad" cable still good to use as a break-out cable? I'd be curious to experiment with the BNC connectors on the back of this monitor...

[MonMotha]

I would expect it to exhibit the same behavior no matter what connector is on the end, but if it's just a matter of a poor connector installation, replacing the connector with e.g. BNCs (which are kinda pricey, mind you) may help.

If you want to make a breakout cable for use with BNCs, I highly recommend getting some quality mini-coax (75ohm) and the proper 75 ohm BNCs.  You should get outstanding image quality if you do this.  The good VGA cables with HD15s on each end are built the same way just without the BNCs.

[Marsupial]

One wouldn't see any difference either from a good VGA cable or via BNC?

I tought there was an advantage to those BNC cables.

Thanks for telling me that.

[MonMotha]

BNC connectors are ever so slightly better for high frequency (high resolution) video signals, but it's not a huge deal.  Sun and SGI used to use the 13W3 connector for video since it let them have 3 mini-coax connectors as well as the other lines for sync, detection, etc. all on one connector.  The PC industry settled on just using the HD15.  It was good enough, and really, you're not going to notice a difference.

However, there are a lot of really crappy VGA cables out there.  The construction method of a BNC breakout doesn't as easily lend itself to the creation of such low quality cables, so you have less of a chance of getting bitten by that with a BNC breakout.  Ideally, the cables would be constructed the same way just with different connectors.