CurtPalme.com Home Theater Forum

[Lar407]

Does anyone know the cause and cure for ghosting through long cable lengths? I'm running my P/C through a Monoprice active 2 way 400mhz splitter with a short run (6ft) to an LCD monitor ( with no problem) and to my NEC XG75 projector ( 75 ft) where I see faint (but annoying) ghosting. I don't know if this issue is related, but I was also picking up an annoying audio hum from the audio side of the splitter via a long cable, which I corrected with an audio ground loop isolator.

Larry

[virusc]

75 is a very long cable. Also splitters are always somewhat detrimental to any video signal. I would connect the projector directly to the 75' cable with the splitter and see if it goes away. You may also have interference from any power cable or bleed thru from other cables.

[Lar407]

I have tried all sorts of variations with the set up and none are better. Taking the active splitter out of the signal path results in rolling and banding. Taking the other devices out of the signal path results in static banding. The ghosting is the least offinsive set up, but it's not good enough for serious video enjoyment. I know pro studios use much longer cables with more coplex routing than mine. Does anyone on this link know what equipment they use to clean up or sabilize the signal?My othe options are to try going digital or to set up media networking.

[virusc]

how about a vga db15 from laptop to 5 BNC cable (6ft) to projector directly. If you get ghosting or any distortion than it is the projector. What resolution are you running. XG's don't like anything above 1024p or so. 75' is very long for RGB video.

[Curt Palme]

Sounds like a poor quality cable perhaps? (the 75' run). I've run up to 160' with an RGB amp at the 1/2 way point with no visible ringing, and minimal overall signal degradation.

[Curt Palme]

Sounds like a poor quality cable perhaps? (the 75' run). I've run up to 160' with an RGB amp at the 1/2 way point with no visible ringing, and minimal overall signal degradation.

[Tim in Phoenix]

Guys!

An Extron device like the 202xi would punch up the signal and might fix the ghosting.

.

[Lar407]

I appreciate everyone's suggestions.

VirusC: I'm already running a 6ft cable from my active splitter to a local monitor without any issue, so I don't
see any benefit to dragging my P/C out of my Office and putting it on a lift in my Media Room to reach
the Projector with a 6ft cable to duplicate the same result. Also, I'm running a safe 1080i resolution to
my NEC XG75.

Curt Palme: Although the cables I purchased were pro-quality from a local supplier who sells pre-owned equip &
supplies, you may be right. I have checked out "broadcast" quality cable on web, but it cost more
than similar length of amplified/equalized HDMI cable.

Tim in Phoenix: The Extron 202xi you recommend is probably better than my splitter,since the Extron
is Pro equip. But if my cables are at fault, spending money on a new switch won't
solve my problem. Again, if the cables are the culprit, it's cheaper to switch to a Digital
connection.

I guess from what everyone has said so far, I should rewire with high quality analog RGBHV Cable and use a pro quality splitter. I'm hesitant in taking this advice because it may not work. Particularly since any of the connections in my chain P/C, Splitter, Key Digital Switch, Extron Scaler, HD-Fury,and Projector, could introduce a slight impedance mismatch. I think I may have a better chance of succeeding by either using a direct Digital feed from my P/C to Projector or Networking my P/C to a source such as the PS3 which in turn would be connected Digitally to my Projector.

Has anyone on this Forum had success with networking from their P/C to their Projector?

[Tim in Phoenix]

[virusc]

Maybe you misunderstood. I would use a laptop to the projector directly with a short cable to see if there is any ringing. It is possible that something in the path of the cable and not the cable itself is at fault or bad porch or phase settings.

[Lar407]

VirusC: I'm sure it's something in the path of the cable, just as you suggest. Since the cable is thick and shielded, it's probably not the
cable itself, but rather some slight impedance mismatch between the equipment it's connected to. I'm not sure why you think it
could be bad porch of phase settings when I'm successfully using these same settings on the Projector from shorter runs via
other sources (not my Office P/C.)

Tim in Phoenix: Yeah, I know the price for an Extron 202i is very reasonable. Still, I don't want to spend $150 for something I already
have. Particularly since my Monoprice unit is amplified, has a 400Mhz bandwidth, and should do the job. I agree with
you in that the Extron is a better piece, and I would buy it in a heartbeat if I thought it would work. There are just too
many other connections that could be causing the ghosting. Example: Splitter port to wall port, wall port to another wall
port (in the other room), that wall port to Key Digital Transcoder ( in pass through mode), Key Digital out port to Extron
Scaler (in pass trough mode), Extron Scaler port to wall port), wall port to Projector's input port.

Like I said earlier, if I took what I felt have been the best suggestions from you guys, it would cost me more to fix this, in both time and money, than it would to switch to a Digital Cable. However, if I do go for a digital connection, networking from the P/C in my Office to a DLNA Source Component in my Media Room may be a better choice. Not sure about that one as I don't have any experience with networking. Are any of you guys networking your sources?